International Hydrofoil Society...

[This article is a composite of material from Work Boat World (Jan2003), the North West Bay Ships web site, and Maritime Dynamic,Inc.; all of whom have granted permission to use this information.]

Maritime Dynamics, Inc. (MDI) active lifting foil system pro-vides hydrodynamic lift to reduce resistance for higher speedor lower power, and greatly reduces vessel motions for im-

proved passenger comfort. MDI’s ride control system electronics co-ordinate the action of the foils.

Their system was proved on Dolphin Ulsan, a 55 meter foil assistedtrimaran ferry (formerly Triumphant; see an article in the Autumn2001 IHS NL, p. 5) built by North West Bay Ships, Australia(www.nwbs.com.au/tri.html). The current owners changed the namefrom Triumphant to Dolphin Ulsan when they purchased it for opera-tion in the Sea of Japan.

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See MDI’s Lifting Foils, Page 3

INSIDE THIS ISSUE

- President’s Column ------------ p. 2

- Welcome New Members ------ p. 2

- Propeller Design ---------------- p. 3

- Gas Turbines -------------------- p. 6

- SCAT Update ------------------- p. 8

- Waterjets ------------------------- p. 9

- Sailor’s Page -------------------- p.10

LETTERThe NEWSInternational Hydrofoil Society

P. O. Box 51, Cabin John MD 20818 USA

Editor: John R. Meyer

MDI’S CUSTOM DESIGNED

LIFTING FOILS

Spring-2004 Sailing Editor: Martin Grimm

The Dolphin Ulsan - Fitted With MDI’s Custom Lifting Foils

IHS Spring 2004

PRESIDENT’S COLUMNJoel Billingsley – Joel became en-amored with hydrofoils when as-signed to the Plainview AGEH-1 asan engineering officer. After histour with the Hydrofoil SpecialTrials Unit, he went on to the NavalShip Engineering Center as a me-chanical engineer engaged in pro-pulsion system design for highperformance ships including thePHM and a large, trans-Atlantic hy-drofoil. He was instrumental in res-cuing the Sea Legs, an earlyexperimental hydrofoil, and findinga home for her at the Mariners’ Mu-seum. This sparked a dream of oneday owning a similar craft.

Peter Cahill - Peter is the personwith Jetfoil moldings of HMSSpeedy 929-320 and the commer-cial 929-115-100. He has beenworking on the Jetfoil model formany years and will soon be able tohave a model fully working withACS. Jetfoil or PHM require thesame type of system for control, Hehas now sourced the outlets for Jet-foil control and hopes to be testingsoon. He feels that in the past therewas a complete lack of knowledgeof the systems for control, but thesesystems are now available. Peter ex-pects to have available molding forPT50, PT75, RHS 150/160/200 andPHM; complete, and ready to run.

Joseph Koelbel –Joe began his ca-reer in naval architecture atSparkman and Stephens in 1947where he worked on the design ofsailboats and an experimental PTboat (PT 810). Since then he hasworked at several naval architec-tural firms and has been in his own

Continued on Page 12

WELCOME NEW MEMBERS

To All IHS Members:

The Society continues to grow with 5new members added to the Member-ship roles during the first 2 months ofthe new year. By the way, you canview the Membership List by loggingonto the IHS website and put in theproper password. All IHS membershave been informed of this password.If you have been missed or forgot,please contact the webmaster. It is ad-visable for all to do this and check theinformation on the List. If it is incor-rect, please send changes to: SteveChorney: [email protected]

All IHS members are reminded thatthere are many offerings on the IHSwebsite these days. You can get allthe information about these on theIHS website. A new addition to theofferings is a CD containing all theIHS Newsletters from 1978-2003.This CD contains a wealth of infor-mation and it also has an Index pre-pared by Martin Grimm. With thisindex one can make a query and lo-cate the issue(s) having the subjectmatter. An example of this is thesearch I was making for speechesmade at the time of the PHM decom-missioning. Martin advised by say-ing: “The speech by Admiral Mauz(an others) is reproduced in the Fall1993 issue of the IHS NL startingpage 8.” Sure enough, there it waswith the other speeches including theCNO’s message stating at the end:“LAND THE SHIPS”. Martin alsomentioned that if one makes a queryon “PHM”, “you will get enough in-formation from past Newsletters towrite a book!”.

I therefore recommend making thissmall purchase of the IHS NewsletterCD by logging onto the website: Theannouncement and ordering instruc-tions are on the front page about halfway down. It is a mere $12.00.

Martin Grimm has passed onto me aninteresting item about RodriquezCanteeri Navali who recently re-ceived a contract for 6 FoilmasterClass hydrofoils. They will be deliv-ered in pairs in 2004, 2005, and 2006.Rodrique claims they can go 40 knotswith 250 passengers and consumeless than 600 litres per hour of fuel.Martin mentions that there is an arti-cle in a recent issue of Work BoatWorld (which I have not seen) enti-tled: “To Foil, or Not To Foil?” Wewill be looking for this and hopefullyobtain permission to extract from itsome material for the SummerNewsletter.

The news about the Foilmasters is en-couraging since most of the newsthese days seems to be about “FoilAssisted” Catamarans, Trimarans, ormonohulls. I’m convinced, in myown mind, that if an operator wants togo 40 to 50 knots consistently inrough water, “Foil Assisting” will notbe satisfactory. He will require a“Fully Foil-Supported” craft;whether it is a monohull, catamaranor trimaran! As a good colleague ofmine used to say: “What goes around,Comes around”. Perhaps all the “FoilAssisted” craft will someday be con-verted to the more conventional hy-drofoil type.

John Meyer

President

IHS Spring 2004

Continued on Next Page

MDI’s LIFTING FOILS

(Continued From Page 1)

The ride control system includes a setof foils that lift approximatelyone-third of the vessel’s displacementat the 40-knot service speed. This en-ables the vessel to achieve its servicespeed with approximately 25% lesspower than competing hull forms.

The lifting foils in conjunction with acenter-hull mounted trim tab, stabi-lize vessel trim and list in addition todamping heave, pitch and roll mo-tions.

The system consists of an active trimtab aft on the center hull and liftingfoils near midships which span fromthe center hull to the outer hulls. Thetrim tab controls the pitch motion ofthe vessel while maintaining opti-mum trim of the vessel.

In addition to generating the neces-sary dynamic lift for the hybrid ves-sel, the lifting foils actively controlthe heave and roll motion of the ves-sel.

Since initial delivery, MDI is retrofit-ting a stabilizing fin aft on the centerhull, near the vessel’s centerline. Thevertically oriented fin is used primar-ily for directional stability.

North West Bay Ships (NWBS) tri-maran vessels have been developedover an extensive design period toprovide a technologically superiorhull form and large platform to suit afull range of marine transport applica-tions.

Trimarans feature an easily drivenlong slender center hull containing alldrive train machinery. This centerhull is supported by smaller side hullsto provide reserve buoyancy and sta-bility for the passenger platform in aseaway.

The result is a vessel authorized (un-der DNV rules) to maintain speed insignificantly greater sea states thaneither similarly sized catamarans ormonohulls.

NWBS flagship trimaran fast passen-ger ferry is the 55 meter DolphinUlsan, which operates a daily returnopen water crossing of the KoreaStrait, total 250 nm, between KitaKyushu, Japan and Ulsan, South Ko-rea.

With most ferry traffic on the KoreaStrait operating into Pusan, theNWBS 55 meter trimaran DolphinUlsan’s run is slightly longer andmore open. The vessel’s ability tocarry significantly increased passen-ger numbers, with reduced operatingcosts allows Dolphin Ulsan to com-pete favorably for passenger share re-

sulting in increased passengernumbers on the route.

Fitted with an active foil ride controlsystem, this vessel achieves an oper-ating speed of 40 knots with 3 x MTU16V 4000 M70 marine diesel enginesdriving through Reintjes VLJ 930gearboxes, with Geislinger carbon fi-bre drive shafts and Kamewa 63 S11water jets.

An equivalent catamaran or monohullrequires 4 engines of equal capacityto achieve the same speeds, addingUS$550,000 to an operator’s annualfuel and engine maintenance costs.

********

(Extracts From Speed at Sea,December 2003)

by Doug Woodyard

Developments in propeller de-sign and. materials continue totarget higher propulsive effi-

ciency and reduced noise and vibra-tion.

Propeller efficiency is now ap-proaching that which is theoreticallypossible, says Rolls-Royce. Greatstrides have been made in developingmore efficient designs in the past 30years but the trend is now flatteningout. On the other hand, significant ef-ficiency advances can be gainedwhen hull/propeller/rudder interac-tion is considered as a whole.

Propeller/rudder interaction leadingto cavitation damage over parts of the

PURSUING PERFECTION IN PRO-

PELLER DESIGN

Lifting Foil Concept

View of outboard starboard hull

and foil

IHS Spring 2004

PROPELLER DESIGN

(Continued From Previous Page)


rudder blade tends to occur on fastvessels with high propeller loadings,and can take place even when the pro-peller itself is cavitation free. Themain cause is the amount of energy inthe slipstream of the propeller,Rolls-Royce explains.

Rolls-Royce has studied the phenom-enon at its Hydrodynamics ResearchCenter in Sweden. The solutions de-veloped include changes to the rud-der shape in three dimensions toavoid self induced cavitation, and abetter integration of hull, propellerand rudder hydrodynamics to avoiddamaging conditions.

The high amount of energy in propel-ler slipstreams can cause other prob-lems, particularly the energy in tipvortices shed by the propeller. Flowconditions downstream of propellersand rudders are now closely scruti-nized since noise from this source canbe fed into the ship’s structure. Thefrequency is much higher than thatcaused by pressure fluctuations atblade passing frequency and can beof concern in passenger tonnage. Pro-pellers have traditionally been a ma-jor source of noise and vibration butbetter blade shapes and highlyskewed blades have contributed to re-duced effects.

Cavitation can be a potent noisesource, particularly with highlyloaded propellers, Rolls Royce notes.Now, however, there is a better under-standing of the various types of cavi-tation, in which local low- pressureareas on the propeller blades causevapor pockets to form, which col-lapse with a hammering noise. Bysuitable design, this can be reduced oreliminated.

Often the propeller designer is con-strained by the ship design, forcingpropellers to be of smaller diameterthan the optimum or to have insuffi-cient clearance between the blade tipsand the adjacent hull surfaces. Lackof clearance also leads to pressurepulses at the blade passing frequencybeing fed into the hull as noise.

Solutions such as contra-rotating pro-pellers can help here, since the totalpower is then split between two pro-pellers which work in opposite handrotation, reducing the blade loading.

R&D is pursued by the classificationsociety ABS in response to the grow-ing problem of propulsion-inducedvibration encountered in service fromboth traditional and innovativepropulsor configurations. The resultsinclude sophisticated analytical soft-ware and continual revision of the rel-evant ABS rule criteria. Analyticalcapabilities have been strengthenedby a series of advanced programs, ei-ther in-house at American Bureau ofShipping (ABS) or as part of joint in-dustry initiatives. These apply com-putational fluid dynamics (CFD) andfinite element analysis (FEA) modelsto assess propeller strength and ana-lyze vibration when verifying de-signs.

ABS has also replaced its empiri-cally-based calculations of the

stresses created by propeller cavita-tion with sophisticated analysesbased on direct simulation using CFDand FEA methods. ABS says it canprovide criteria for propeller designsthat limit vibration.

Many unconventional propulsor de-signs have emerged in recent years asdesigners have sought to minimizethe level of propeller cavitation andthe associated vibration. Among suchinnovations are highly-skewed pro-pellers, tractor pods, propellers withwake-equalizing ducts and spoilers.

Numerous contracted and loaded tip(CLT) propellers are now in serviceor on order worldwide with tonnageranging from fishing vessels and highspeed craft to diverse merchant ships.The installations cover a power bandup to 26.5MW and are applied tofixed and CP hub designs.

Sistemar, the Spanish designer, citesthe following merits for the CLTpropeller:- reduction in fuel consumption ofmore than 8 % or an increase in shipspeed for the same consumption- reduction/elimination of hull-in-duced vibrations- improved maneuverability (smallerturning circle and shorter stoppingdistance in crash stops)- enhanced course stability.

Among the references is a twin-screw installation on the 7,200 dwtRoRo freight carrier Superfast

Levante. A service speed of 22 knotswas sought from the four 6,300kWmedium speed engines driving4.5m-diameter propellers with ablade area ratio of 0.48. The CLTblades, designed by Sistemar andbuilt by Navalips of Cadiz, aremounted on CP hubs from John

CLT blades installed on Superfast

Levante

IHS Spring 2004

PROPELLER DESIGN

(Continued From Previous Page )


Crane-Lips (now Wartsila Propul-sion). Sistemar reports that the ship’sspeed is over 23.5 knots.

Given the comparatively high pro-pulsive power installed - 12.6MWper shaft - the owner, Trasmedi-terranea, was keen to ensure therewould be no excessive propeller cavi-tation that could cause unacceptablehull vibrations and blade erosion. In-dependent hull vibration studiesshowed that: the cavitation level de-veloped on the CLT blades was negli-gible from the ship’s structuralintegrity viewpoint; vibration andnoise levels were excellent in termsof onboard comfort; and the contrac-tual ship speed was much better thanpredicted.

Most propellers in service today weredeveloped using theories based onhelical surfaces with straight genera-tor lines. A different class ofpropulsor with enhanced efficiency isthe propeller with non-planar liftingsurfaces (that is, no longer based on ahelical surface with a straight genera-tor line). An example is the Kappelpropeller with blades smoothlycurved towards the suction side andapplying non-planar lifting surfaces.

In line with predictions based onmodel tests, it was determinedthrough sea trials that the Kappel pro-peller reduced power consumptionby four per cent at 15 knots comparedwith the original conventional pro-peller installed on the tanker.

The cavitation appearance of bothpropellers was very similar to the ap-pearance in model scale, although thefull-scale conventional propellershowed a pronounced stronger tipvortex. The full-scale pressure pulse

level measured was very close to pre-dictions in the case of the conven-tional propeller. The level generatedby the Kappel propeller was pre-dicted to be lower than for the con-ventional propeller, but the full-scalemeasurement showed it yielded amore significant reduction of thepressure pulse levels (averaging 40per cent).

Kappel propellers can be supplied asfixed pitch or controllable pitch de-signs for single screw and multiplescrew as well as for contra-rotatingpropeller systems.

Continuing sales are enjoyed by thepropeller boss cap fins (PBCF) devel-oped by Mitsui OSK Lines, the WestJapan Fluid Engineering Laboratoryand Mikado Propeller. First installedin 1987, the system now serves over830 ships.

Applicable at the newbuilding stageor by retrofit to fixed and CP propel-lers, the PBCF system exploits a bosscap with fins that rectify the propellerhub vortex and recover rotational en-ergy otherwise lost in the slipstream.Propeller thrust is reportedly in-creased by over one per cent and pro-peller torque reduced by more thanthree per cent, thereby underwritingfuel savings of up to five per cent. Aspeed gain of two per cent can be de-livered with the same engine output.Apart from enhancing propulsive ef-ficiency, the PBCF is said to reducestern vibrations and propeller noise,and resolve a number of rudder ero-sion problems.

Advances in materials technology areexploited by designers, sea trials ear-lier this year demonstrating the prom-ise of Qinetig’s composite propeller.The world’s largest composite pro-peller (2.9m-diameter and weighing

much less than a traditional equiva-lent cast from a nickel-aluminum-bronze alloy) was successfully testedon the Qinetiq’s trimaran warship

prototype, Triton.

Featuring five rigid composite bladesbolted and bonded to a traditional al-loy hub, the propeller replaced thevessel’s original fixed pitch unit. Im-mediate benefits were noted on trialsfrom the smooth take-up of powerand reduced vibration.

Using lighter composite material al-lowed the blades to be thicker with-out significantly adding to the weightof the propeller. Thicker blades offerthe potential for improved cavitationperformance, so reducing vibrationand underwater signatures.

Lower weight will be particularly at-tractive to podded-propulsor design-ers. The weight saving in this initialapplication was around 20 per centbut savings of 30-40 per cent are con-sidered possible if the hub is alsomade of composite material.

Qinetiqs composite propeller pic-

tured on the trimaran Triton

IHS Spring 2004


PROPELLER DESIGN


Led by UK-based Qinetiq, the devel-opment project involved Dowty Pro-pellers, which manufactured thecomposite blades, and Wartsila Pro-pulsion, which produced the nickel-aluminum-bronze hub and assembledthe propeller.

Summarizing the potential benefits ofthe composite propeller, Qinetiqcites: weight saving, reduced corro-sion effects, improved vibration char-acteristics (tunable frequencyresponse), reduced wear on gear-

[This is the continuation of the arti-cle appearing in the Winter 2003-2004 issue extracted from Speed atSea, August 2003]

Rated at 25MW, the WR-21 isbased on the successful Rolls-Royce aero RB211 and Trent en-

gines with modifications to marinisethe components and effectively inte-grate the heat exchangers and variablegeometry. The first seagoing installa-tions (featuring twin sets) will enterservice from 2007 in the UK RoyalNavy’s new Type 45 D class destroy-ers. The fuel consumption character-istics - approximately 205 g/kWhfrom full power down to around 30per cent power - enable the WR-21 tofulfil the role of both cruise and boostengines.

Compared with simple-cycle tur-bines, the benefits cited for theWR-21 include an improvement infuel efficiency over the entire operat-ing range (with a radical improve-ment at low power), easiermaintenance through enhancedmodularisation, and the facility to ret-

IMPROVED GAS TURBINES READY

FOR UPTURN

rofit ultra low emission reduction sys-tems.

Rolls-Royce continues to promote itsmarine Spey gas turbine for fast com-mercial vessel projects requiring sus-tained unit power outputs of 18MW (arating of 19.5MW is quoted for navalduty).

The marine Spey first went to sea in1985 and is now in service in ninewarship classes, including the RoyalNavy’s Type 23 frigates and a numberof vessels in Japan’s MaritimeSelf-Defence Force.

Currently extending the reference listis the Royal Netherlands Navy’s newLCF air-defence command frigates, aclass of four headed into service lastyear by HNLMS De Zeven

Provincien. A maximum speed of 28knots is secured by the twin 19.5MWSpey components of the CODOGpropulsion plant, while two 5,000 kWdiesel engines are deployed for cruis-ing at up to 18 knots.

At the other end of the Rolls-Roycepower spectrum, the compact andlightweight Allison 501 gas turbineaddresses propulsion and auxiliarydrives requiring outputs from3,900kW to 5,400kW. Derived fromthe T-56 aero engine, which powers anumber of civil and military aircraft,the twin-spool, hot end drive Allison501 is particularly suited to Jetfoil andhydrofoil propulsion. Over 130 highspeed craft are currently served andapplications include fast patrol boatsand cruise power installations forfrigates.

Success in commercial and militarypropulsion markets can be claimed byUS-based Vericor Power Systems forits TF-series gas turbines, adapted formarine use from Honeywell’s aero

engine designs. A programme basedon the TF40 and TF50 turbines andtheir respective twinned TF80 andTF100 configurations cover a maxi-mum continuous power band from3,432kW to 7,409kW

More than 500 TF40 and TF50 tur-bines are reportedly in service world-wide, the reference fleet includingfrigates, corvettes, fast offshore patrolboats, missile craft and hovercraft.

Four TF50A sets in a CODOG con-figuration were specified for theRoyal Swedish Navy’s Visby-classcorvettes commissioned from the do-mestic yard Kockums with ‘stealth’characteristics. The turbines - drivingtwin waterjets via two gearboxes - aredeployed for full power mode, whileMTU 16V 2000 high speed dieselengines are engaged for loitering.

Twin TF40 turbines drive both thepropulsion and lift fans of the FinnishNavy’s T2000 combat air cushion ve-hicle, built by Aker Finnyards.

Upgraded TF40B turbines are beingsupplied for a service life extensionprogram for the US Navy’s fleet oflanding craft air cushion (LCAC) ve-hicles. Over 400 TF40Bs deliveredfor the fleet have together loggedmore than 400,000 operating hoursunder demanding conditions. The en-hanced engine, designated theETF40B, generates 15 per cent morepower (at maximum intermittent rat-ing) and promises improved fuel effi-ciency and significantly reducedlife-cycle costs than the original de-sign.

The 118 Wallypower fast yacht, builtby Intermarine in Italy for WallyYacht, features three TF50 turbines aspart of a 12.53MW CODOG propul-

IHS Spring 2004

Interested in hydrofoil history,

pioneers, photographs? Visit the

history and photo gallery pages

of the IHS website.

http://www.foils.org

Disclaimer

IHS chooses articles and

photos for potential interest to IHS

members, but does not endorse

products or necessarily agree with

the authors’ opinions or claims.

GAS TURBINES


sion plant delivering a cruising speedof 60 knots and a maximum speed of70 knots. And the megayacht Detroit

Eagle, built in The Netherlands byFeadship de Vries, is powered by aCODAG system incorporating aTF50 turbine.

Another contender keen to serve thecommercial shipping market as a sup-plier of integrated gas turbine and die-sel engine packages, Germany’sformidable MAN B&W Diesel groupteamed up with MAN GHH Borsig, apackager of Pratt & Whitney FT8 gasturbines for mechanical and generatordrives. Based on Pratt & Whitney’sJT8D turbine, the aero-derived FT8 israted at 25.5MW in standard form and27.25MW in uprated FT8+ form.

A strong commercial, leisure and mil-itary propulsion pedigree is claimed

by Pratt & Whitney Power Systems,over 300 gas turbines having beensupplied for diverse vessel types.Smaller aero-derived designs such asthe ST series offer base power outputsextending up to 4,000kW, with a4,900kW peak rating. A free powerturbine element suits variable speedmechanical drive duties imposed bypropeller and waterjet propulsors.

Lower operating costs through burn-ing cheaper fuels than the light gasand diesel oils normally required byaero-derived gas turbines are prom-ised by Alstom Power, which inher-ited the lightweight industrial-basedturbine interests of Sweden’s ABBStal. Successful fast ferry service ex-perience on IF30 intermediate fuel iscited for its GT35 turbine, with a ca-pability to burn IF180 fuel. The de-sign has an output rating of 17.3MWat 3,450 rpm for mechanical drive ap-plications, with an efficiency of 33per cent.

A Japanese challenge in theaero-derived marine gas turbine mar-ket was spurred by the country’sTechno-Superliner (TSL) fast freightcarrier project of the early 1990s,which called for an indigenous highoutput prime mover with a very lowweight. In response, Mitsubishi cre-ated the MFT-8 from the marriage ofits own power turbine and the GG-8gas generator from Pratt & Whitney.

After the prototype achieved a fullpower rating of 24.3MW during shoptrials, two production sets were deliv-

ered for installation in the TSL craftbuilt by Mitsubishi. The Japanese de-signer subsequently offered theMFT-8 turbine to the wider marketwith a propulsion plant rating of25.79MW and a thermal efficiencyapproaching 39 per cent.

Experience in supplying sets for theformer Soviet Navy and some over-seas navies is tapped by theZorya-Mashproekt Gas Turbine Re-search & Production Complex inUkraine, its portfolio embracing ma-rine designs with outputs rangingfrom 3,000kW to 27.5MW

Projects in recent years have includedpropulsion and auxiliary power gasturbines for large Zubr-type landinghovercraft commissioned by theGreek ministry of defence from Rus-sian and Ukrainian yards. Each pack-age comprises five DP71L2 turbines(with individual ratings of 7,355kWat 40 degrees C ambient) arranged todrive the air propellers and horizontalair cushion fans. The three-shaft tur-bine can deliver 7,800kW.

More powerful turbines have beensupplied by Zorya-Mashproekt forfrigates and destroyers ordered byChina and India from Russian yards.Twin-screw COGAG plant for IndianNavy frigates, for example, incorpo-rate pairs of UGT-6000 andUGT-16000 reversible turbines, themodel designations reflecting the rat-ing in kW.

Pratt & WhitneyAero-derived FT8

TF50A Gas Turbine Engine

IHS Spring 2004

Extract from “The History of Hydro-foils” by Leslie Hayward in“Hovering Craft and Hydrofoil”,provided by Martin Grimm, IHSMember.

Apatent of considerable interest

is US Patent 1,187,268, grantedto G.A. Crocco of Italy in 1917.

The proposed foil system is the fore-runner of those employed on manypresent-day hydrofoil craft.

Crocco’s proposed foils are of the ca-nard type, and although a submergedas well as a surface-piercing systemwas proposed, the surface-piercingsystem appears to be of the greaterinterest and practical importance.

A BIT OF HISTORY - CROCCO’S HY-

DROFOIL

For the surface-piercing systemCrocco proposed a complete V bowand an incomplete V stern foil (Figs30 and 31). Modern developmentshows that this type has good pitchand roll stability.

Crocco and his fellow experimenterRicaldoni had been engaged on hy-drofoil development for about tenyears and they developed a craft sup-ported by a monoplane dihedral foil,illustrated in Fig. 32.

The craft, displacing 1.5 tons andpowered by an 80 hp engine, attaineda reported speed of 50 mph. Used totest airship engines, this craft was thefirst to employ inclined single sur-face-piercing hydrofoils bow andstern. Crocco was the first man to suc-cessfully execute a take-off in a hy-drofoil-supported seaplane; but thelanding was much less successful; thecraft nosed over and Crocco almostexecuted himself.

By Sam Bradfield, IHS Member

Here’s where we are as of today(Feb 19, 2004). Every week anew challenge, right?

Our minimum takeoff true (ambient)windspeed with 7000 lbs displace-ment and 1900 sqft sail area is 11 to13 kts. Our minimum takeoff boatspeed is 13 kts. The apparentwindspeed at which takeoff boatspeed is attained will vary dependingon the heading to the true wind.

On Feb 15, we finally hit our “flightdesign point boat speed” for SCAT;31.6 kts reaching on the river withwind in the 15 to 20 kt range. Ourriver course is of length about 3 ½ nmof the IC Waterway in front of theFlorida Tech Anchorage where weslip our boat. We had a blustery westwind and a river chop interspersedwith wake from the waterwaythru-traffic...not too bad. Over mostof the run boat speed was averaging26 to the 31.6 kt max.

The small chop made it a pretty roughride. Larger wakes were present butSCAT eases through them no prob-lem. Our foil extension was only 6 ftbecause of the shallow water but itworks OK with the small chop. 8 ftextensions are used for ocean sailing.

Our next ocean outing is the Mi-ami-Nassau Race March 19. It’ll beour first scrimmage with othermultihulls in our class. PhilipSteggall, experienced ocean racer, isgoing to lead the crew of three expe-rienced RAVE hydrofoil racers:Mike McGarry, Hollis Caffee, and

SCAT UPDATEKeith Zwart. Tom Haman and I aresitting this one out although Tom willbe bringing the boat back fromNassau.

Based on our experience up to now, Ibelieve SCAT will be OK for boatspeed up to 35 kts beam reaching insteady wind (in flat water)...our“maximum speed design condition”.I also believe her speed made goodwhen flying close reaching to 60 de-grees will be very competitive in hermultihull class. We’ll get more infofrom this next race. We think we’rerace-ready now except we need topractice some spinnaker runsfoilborne this coming weekend.

IHS Spring 2004

SEALIFT STUDY OPTS FOR AXIAL

FLOW WATERJETS

(Extract from Speed at Sea, Decem-ber 2003)

by David Foxwell

Ongoing research and develop-ment work in the USA suggeststhat axial-flow waterjets, rather

than mixed-flow waterjets of the typewidely used on fast craft to date,could be the most efficient and effec-tive means of propelling the next gen-eration of naval high speed craft

Waterjets offer a number of advan-tages for high speed craft comparedwith other types of propulsor - such asreduced drag, reduced draft, im-proved maneuverability, reducedstopping distance and reduced noiseand vibration - and it is interesting tonote that all of the proposals put for-ward in the current phase of the 40-50knot littoral combat craft programmemake use of waterjets rather than con-ventional propellers, as do a numberof other high speed craft in which theUS Navy has expressed an interest.

Low-drag slender hulls will be essen-tial for the next generation of highspeed craft, but slender hulls make itmore difficult to install the machinerynecessary to achieve high speed. Aconventional propeller with exposedshaft, shaft supports, and rudder ex-periences significant drag, and ad-versely affects the desired hull shape,so that, above 25-35 knots, waterjetpropulsion has been increasingly thepropulsion system of choice.

In fact, waterjet propulsion has manydesirable features for high speedcraft, because the propulsor can bemounted within the hull - which elim-inates ‘appendage drag’ - and thehull-mounted waterjet inlet is an in-

herently low-drag type arrangement,especially when installed flush withthe hull. Steering is accomplished bydeflecting the jet nozzle flow, andbecause the steering systems can belocated out of the free-stream flowthey cause little additional drag.

In addition to producing minimaldrag, waterjets also have perfor-mance benefits that allow for highpropulsive coefficients or efficien-cies to be attained - propulsive coef-ficients in the 60 to 70 plus per centrange being achievable for very highspeed waterjet propelled vessels.

High speed ships will require enor-mous amounts of power for any shipof meaningful commercial size, andhigh propulsive efficiency will be animportant consideration for botheconomic and ship impact reasons.Marinised gas turbines will undoubt-edly be the primary power source forany large high speed vessel, and theultimate size of the ship will dependnot only on the ultimate designspeed, but also on the number of gasturbine engine and waterjet units thatcan be installed in the space avail-able.

These conflicting requirements ofslender hulls and large amounts ofinstalled power with multiple

waterjets have led to the need to de-termine the best hullform and propul-sion machinery arrangement for highspeed sealift ships, and the develop-ment of a new generation of advancedwaterjets for the next generation offast craft has been identified as a keypriority by the US Navy, leading to awide-ranging programme of researchand development work, much of itconducted by CDI Marine Com-pany’s systems development division(formerly Band, Lavis & Associates)in Severna Park, Maryland, USA.

CDI Marine has extensive marine

waterjet experience, having workedwith Bird Johnson (nowadays part ofRolls-Royce Marine) and the De-fense Advanced Research ProjectsAgency on the development of largertypes of pumps, on pumpjets for theUS Marine Corps, axial and axial in-ducer waterjets for the US MarineCorps, axial inducer waterjets for fastscalift ships, large axial flow waterjetdesigns for the Office of Naval Re-search, and on a number ofhull/waterjet interaction studies.

[Editor’s Note: The second part ofthis article will appear in the Summer2004 IHS Newsletter.]

5-bladed waterjet rotor design using TURBOdesign

IHS Spring 2004


SAILOR’S PAGE

Report by Rohan Veal, International

Moth Class Association.

Photos by M. Poitevineau - Sports

Nautiques Sablais

[Continued from Winter 2003-2004IHS Newsletter.]

Veal’s Hydrofoil Development…

Rohan Veal’s 9.5kg Prowler hull isfitted with hydrofoils manufac-tured by John Ilett at Fastacraft

in Perth, Australia. These consist of afully submerged T-foil centerboardand similar T-foil rudder both madefrom a mould using pre-preg carbonfibre. Both are on the centerline of theboat. The centerboard is a very thinstraight section blade (120mm x14.5mm) angled forward from thehull towards the foil to stop air travel-ing down the blade. An 800mmNACA 63412 hydrofoil wing(120mm x 14mm) is mounted at itsbase. The rudder is also a symmetricalsection with straight planform and ismounted from a large carbon fibreoutrigger attached to the transom.This is used to increase the longitudi-nal distance between the two foils andso improve pitch stability.

The two foils each have an adjustableflap at the trailing edge. The center-board is automatically adjusted by aride height sensor arm mounted at thebow on a moulded carbon fibrebracket. The ride height sensor arm isa tapered fiberglass batten that is in-serted into a slightly bent alloy tube.This tube attaches to a hinge on thebow and allows the arm to swing upand down so that it skims the waterssurface. The constant touching of thewater is maintained by some 2mm

FOILING AT MOTH WORLDS IN

FRANCE

spectra passing through a micro pul-ley on the bow and attached to shockchord that leads back into the boat foradjustment. An adjustable cable thenattaches to the top end of the alloysection on the control arm, and leadsback into the cockpit where it mountsonto a block just in front of the center-board case. The end of this cable atta-ches to a pivoting arm at the top of thecenterboard, which in turn activates athin fiberglass leading down the cen-terboard to the flap.

As the hull rests in the water at lowspeeds, the control arm is pushedback which in turn adjusts the trailingedge flap so that it induces maximumlift on the centerboard hydrofoil to as-sist takeoff. Onceairborne, the con-trol arm dropsdown to the water’ssurface with the aidof the shock cord,thereby adjustingthe trailing edgeflap and reducingthe amount of liftgenerated. Withoutthis control, theboat would simplywant to keep onlifting until the foilbreaks through thewater’s surface. Thiswould promptly befollowed by a spectacular crash land-ing of the boat.

If the foil does break the water’s sur-face in waves, this is usually followedby a rather loud underwater explosionlike a bomb going off underneath theboat. The effect is only increasedwhen traveling at high speeds due tothe increase in pressure around thefoil. From Veal’s experience, hydro-

foil ventilation or cavitation is onlycaused when sitting too far back onthe wing bar or when sailing into a bigwave. However this is easily counter-acted by doing one or all of the fol-lowing. Firstly more tension can beapplied to the shock cord whichforces the end of control arm to digdeeper in the water and hence reducethe lift on the main foil. Secondly,move body weight forward once theboat is airborne to reduce the angle ofattack and hence reduce lift on bothfoils. Finally, the rudder also has anadjustable trailing edge flap that canbe manually controlled by means oftwisting the tiller extension in eitherdirection to regulate lift.

When the conditions in Les Sablesproved ideal for hydrofoiling, Veal’son-water speed and display wasamazing. Using a GPS, he regularlyclocked over 18 knots of boat speedin about 15 knot sea breeze. Veal alsomanaged to perform gybes and tackswhilst completely airborne, provid-ing a great spectacle for onlookers,

An Amazing Balancing Act by Rohan Veal sailing

“White Knuckle Express” in 2003, France

IHS Spring 2004

not to mention if it was followed byan airborne catapult. Veal also com-ments that it is extremely enjoyablewhen foiling, especially when pass-ing Hobie catamarans and Formulasailboards in 10-15 knots.

Surprisingly it is also quite easy tosail fast upwind in waves. Instead ofpunching through waves, the boatsimply sails completely over the topof them making the ride a lot morecomfortable. This necessitates sittinga long way aft in order to maintain ahigh angle of attack on the foils forthe more moderate speeds. It is an un-usual feeling at first, but with an ex-tremely efficient sail and light weightboat, it powers up immediately al-lowing the skipper to heel the boat towindward whilst completely air-borne to carve a path upwind just ashigh as a conventional Moth configu-ration would sail, but at greaterspeed.

Tacking involves slowing the boatdown to a comfortable speed byslowly pointing up into the wind. Aspressure decreases in the rig, the boatwill try to lift slightly, however this iscontrolled by moving body weightforward and making small adjust-ments in the rudder flaps to keep thebow down. With practice, hydro-foiling Moth sailors could tack quitecomfortably and no differently to aconventional moth, yet be foilingagain on the new tack within sec-onds.

Downwind is also a treat as it is nowpossible to tack down a square run atspeed instead of trying to balance onthe boat like an acrobat [ed: the cur-rent generation of narrow Moth hulls

are inherently fairly unstable].Reaching is also the best part ofFoiler Moth sailing, but it also addsthat extra fun, speed and excitement,not to mention the tactical advantagein picking the favoured side of the runthat has more pressure or sailingfaster with more apparent wind.

Gybing is by far the most challengingpart of sailing a hydrofoiled Moth, asit involves a lot of controlled speed. Ifyou sail too fast, you might go toohigh when you gybe. If you sail tooslow, you’ll probably drop the newleeward wing in the water and tipover (and that’s not uncommon whengybing slow conventional Moth any-way). A perfect “foil-to-foil” gybe in-volves a manageable speed andleaning into the boat so that the lee-ward wing is close to the water’s sur-face, while at the same time, makingrudder flap adjustments so that thebow does not lift up. The boat will al-most turn itself slowly, but one verysmall constant rudder trim will beenough to get you on the new gybewith the boat now healed to wind-ward and the helmsman on the newwindward wing. The mainsheetshould never need to be sheeted outmuch anyway, so the boom shouldcome over fairly easily, but a quickflick of the main on the way throughthe gybe, will see a fully battenedmain flip over. From here, the boatshould still have enough speed to beairborne. If the boat touches the wa-ter, it will be back up in no time with afully powered mainsail.

Even after mastering the basics ofsailing this new Moth, using the hy-drofoils still proved to be a gambleeach day at the Worlds, as a competi-tive run relies on ideal weather condi-tions for foiling. Before any race, itcould be perfect foiling conditions,

but an hour later, the wind could eas-ily drop off to nothing. The drag cre-ated by the large foils when hullbornethen becomes a disadvantage.

Even though the International MothClass Association have banned theuse of transversely mounted foils, notall members of the International MothClass Association believe that hydro-foil development in the form of T-foilcenterboards is the best direction forthe class, even though the currentclass rules do not prohibit them or in-deed a change in configuration duringa championship to suit conditions foreach heat.

There is mixed reaction betweenmembers, however history tells usthat controversy over issues such asthe foils is not all that uncommon inthe class. In the 1980’s AndrewMcDougall was the first to win anAustralian Championship in a skiff,breaking away from the traditionalscow type Moths that had been pres-ent since 1928. Traditional scow sail-ors saw this as anarchy, but‘development’ was the primary objectof the class, so the skiff Moths domi-nated from then on and have pro-gressed to the slim 300mm wide boatsthat are seen racing all over the worldtoday.

The Moth class has been, and alwayswill be, the only true international de-velopment class, and so will continueto take a lead into the future of sailing.

More info, photos and videos can befound on the following web sites:

www.rohanveal.comwww.moth.asn.auwww.moth-sailing.orgwww.fastacraft.comwww.kasail.com

FOILING


IHS Spring 2004

IHS OFFICERS 2000 - 2001

John Meyer President

Mark Bebar Vice President

George Jenkins Treasurer

Ken Spaulding Secretary

GOOD BENEFIT

IHS provides a free link from

the IHS website to members’ per-

sonal and/or corporate site. To re-

quest your link, contact Bill White,

IHS Home Page Editor at

[email protected]

WELCOME NEW MEMBERS


IHS BOARD OF DIRECTORS

2001-2004 2002-2005 2003-2006

Sumi Arima Jerry Gore Mark R. Bebar

Malin Dixon Jim King William Hockberger

John R. Meyer Ken Spaulding George Jenkins

William White John Monk Dennis Clark

consulting business. While withGrumman’s Marine EngineeringDepartment he was responsible formost of the naval architectural as-pects of hydrofoil craft includingthe H.S. Denison and the AGE(H)Plainview. He contributed to para-metric performance studies andeconomic analyses for hydrofoil ap-plications worldwide. While chiefnaval architect for Atlantic Hydro-foils, Inc. he was engaged in the de-sign of hydrofoil boats, foil assistedcatamarans, planing boats, andlarge displacement vessels, includ-ing short run high-speed passengerferries, sight-seeing boats, theCoastal Patrol and InterdictionCraft (CPIC), and ferries for theState of Massachusetts. Joe’s pres-ent interest in hydrofoils stems fromhis work with Eugene Clement in adevelopment of stepped hull tech-nology. In contrast to the usual con-figuration, which has the afterbodyplaning on the wake of the forebody,this design uses a hydrofoil as astern stabilizer and aft lifting sur-face.

Stephen McDonald – Stephenspent six years in the USS Subma-rine Service stationed aboard theUSS Trumpetfish (SS425). He wasa sonar tech second class and en-joyed every minute of it. He is pres-ently the CEO of a wholesale

Historic First Nationals on Foils!Just want to let everyone knowthat Rohan Veal of the Moth

Class has an insurmountable lead inthe Australian Moth Nationals. He issailing a Moth on hydrofoils! This isthe first time in history that a hydro-foil equipped boat has won a Na-tionals using foils. It is clearly adramatic step forward for hydrofoilsand sailing in general! He has wonfive races against 30 plus boats byleads of three to nine minutes. In therace he won by nine minutes secondplace was also a hydrofoil! Rohansboat sails on just two foils: one on thedagger-board and one on the rudder.Altitude control is by use of a “wand”system. Stability is provided entirelyby the crew. The boat and foils werebuilt by John Ilett of Perth WesternAustralia and he deserves congratula-tions as well. Doug Lord; Email:[email protected]

INTERESTING MESSAGEproduce company in New York, andhas just gotten back into modelingafter an absence of about fifteenyears. About twelve years ago hepurchased and put in storage twohydrofoil model kits . One pur-chased from a shop in England is aGerman Police Boat manufacturedby the Hegi company and the otheris the VS-8 German hydrofoil kitpurchased here in the U.S. from the32nd Parallel. Stephen actually hap-pened across the IHS searching forhelp to build these two kits. Read-ing a lot of the old messages on thebulletin board has been a great help,especially from Mr. Martin Grimm.

Other New Members include:

Johnny Dominguez – Johnny isfrom Guayaquil, EcuadorAndrew Essex - Andrew is fromLincolnshire, UKAlexander Karas - Alexander isfrom Baltimore, MDJames T. Lang – James is fromPalo Alto, CAAdrian Motie – Adrian is fromAshford Middx, UKMax Runyan - Max is from Hun-tington Beach, CAGareth Watson - Gareth is fromNorth Yorshire, UKChung Leung Yung - Chung isfrom Hong Kong, China

(Extracted from Rinspeed web site www.rinspeed.com)

Rinspeed Splash - A Dream Comes TrueIn what has become a fond tradition Rinspeed Design, the Swiss cre-ative powerhouse for automotive concepts and emotions, presentedyet another surprising and astounding attraction at the Geneva MotorShow in March. To celebrate their 10th concept vehicle the Rinspeedcrew has created the Rinspeed “Splash”.

Under the ultra-light carbon-composite skin lies much more than justan agile and lively sports car. The Rinspeed “Splash” is the true incar-

WHERE ARE YOU IN

CYBERSPACE?!

IHS relies on electronic commu-

nication with the membership to im-

prove timeliness and reduce mailing

costs. If you are a member with email,

let us know your email address!

Thank you.

2004 DUES ARE DUE

IHS Membership is US$20 per

calendar year. Your renewal or new

membership is critical. IHS accepts

dues payment by personal check, bank

check, money order or cash (all in US

dollars only). We have also arranged for

payment of regular membership dues by

credit card using PAYPAL. To pay by

credit card please go to the IHS mem-

bership page at www.foils.org/member.htmand follow the instructions.

See SPLASH, Page 3

INSIDE THIS ISSUE

- President’s Column ------ --- p. 2

- Welcome New Members ---- p. 2

- Seascape Yacht --------------- p. 4

- To Foil or Not to Foil -------- p. 5

- High Flying Banana --------- p. 6

- PHM Kit ----------------------- p. 8

- Sailor’s Page ----------------- p. 10



Editor: John R. Meyer

IT’S A HYDROFOIL, IT’SAN AUTO........

IT’S BOTH!!!

Summer-2004 Sailing Editor: Martin Grimm

Splash on Foils

IHS Summer 2004

PRESIDENT’S COLUMN Louis Adamo – Lou received hisdegree in physical oceanographyfrom Johns Hopkins, and workedfor many years in ocean windwaves. He closed the loop on largeforecasting systems by integratingDatawell’s Waveriders into practi-cal, satellite-reporting, wave datasystems. His current interests are infast, coastal, passenger ferries as al-ternative transportation to free-ways, rail, and air shuttles.

William E Eisenhower Sr. – Mr.Eisenhower was born in westernPennsylvania, and grew up in Phila-delphia suburbs. He retired from USNavy as a Chief Aviation Electron-ics Technician, having served withAirships, on a Destroyer, an AircraftCarrier, Aircrew on C47 and P3Caircraft and as an Instructor atMonterey Naval PostgraduateSchool. He has been employed as aComputer programmer, Interna-tional field engineer, ConfigurationManger for DOD Contractors andpresently support the Navy F18 E/FProgram. With interests in hydro-foils, other fast ship designs, andother than oil-based power plants,Bill is as an enterprising dreamerwith no preconceived limits.

Robert J. Etter – Bob has workedat NSWCCD (DTMB) for the past20 years. Prior to that he worked for18 years at Hydronautics, Inc. andparticipated heavily in the Navy’sSES Program. He designed the vari-able-area flush waterjet inlet systemfor the SES-100A, conducted de-sign and test work for both Bell andRohr for the 2KSES/3KSESwaterjet propulsion systems and de-


WELCOME NEW MEMBERS

To All IHS Members

Several issues ago, I mentioned thatthe IHS Board of Directors was com-mitted to a “soul searching”, “plan-ning” effort in which we wouldreconsider IHS objectives/goals andplay them against ongoing and pro-jected activities. Board memberDennis Clark is leading the planningeffort. In March of last year, he pre-sented a “Planning Framework andApproach”. The initial step was aPlanning Meeting held on September10, 2003. It was attended by six of theBoard members and two invitedguests who have served as Boardmembers previously. Recently Soci-ety five Goals were established in thefollowing areas:

Goal #1: Communication ToolsGoal #2: Knowledge ManagementGoal #3: MembershipGoal #4: Educational OutreachGoal #5: Society Management

“Desired Outcomes” were then de-veloped for each of the Goals and pri-orities set for each in accordance withthe following definitions:

A-Primary Importance. (in process,required to support other initiatives,etc.) Resources (manpower, funding,expertise) presently available.B-Primary Importance. Resourcesnot yet available or requires comple-tion of other Dos.C-Secondary importance. Resourcespresently available.D-Secondary importance. Resourcesnot yet available, or requires comple-tion of other DOs.

A comprehensive report will be forth-coming sometime after the Board ofDirectors meeting in June at whichtime the Planning Process” will bewrapped up.

The Society continues to grow with14 new members added to the Mem-bership roles during the first 5 monthsof this year. By the way, you can viewthe Membership List by logging ontothe IHS website and put in the properpassword. All IHS members havebeen informed of this password. Ifyou have been missed or forgot,please contact the webmaster([email protected]). It is advis-able for all to do this and check the in-formation on the List. If it isincorrect, please send changes to:Steve Chorney:

IHS is a volunteer member organiza-tion. Many of the hydrodynamic andother technical questions posted onthe bulletin board have been an-swered by Barney Black, Tom Speersand Martin Grimm, and others. IHSthanks them for their participation.The IHS Board of Directors wouldlike to see more members contributelike these members to enhance our or-ganization.

I cannot over-emphasize the amountand nature of the pertinent technicalpapers and reports that reside on thetwo Advanced Marine Vehicle CDsthe IHS has produced. If you have notacquired these CDs, you should do sofrom the IHS website.

John R. Meyer, President

IHS Summer 2004 Page 3

SPLASH


nation of a really cool and fun sportstoy. At the push of a button a clev-erly thought-out hydraulic mecha-nism transforms the sports car intoan amphibious vehicle. But thatalone wasn’t enough for Frank M.Rinderknecht, founder and boss ofRinspeed. A highly complex inte-grated hydrofoil system enables the“Splash” to ‘fly’ at an altitude ofabout 60 cm (just under 2 feet)above the water.

The almost magical transformationfrom a street vehicle into a floatingand ‘flying’ all-rounder is madepossible by an electronically con-trolled hydraulic system with an ar-ray of sophisticated sensors.

The transformation starts with thenondescript rear panel, which flipsup to reveal a Z-drive in horizontalrest position, borrowed from awatercraft. The Z-drive is fittedwith a conventional 3-bladed pro-peller and can be lowered to its fully‘standing’ position from the cock-pit. The position of the drive is infi-nitely variable, which guaranteesimmediate propulsion upon enter-

ing the water. A custom-designedtransfer case sends power to the rearwheels, the propeller or both, de-pending on the input from the pilot.Starting at a water depth of about1.1 meters the Z-drive can be low-ered all the way to its fully ‘stand-ing’ position. Steering commandsare entered via the steering wheeland transferred to the Z-drive.

At a minimum water depth of about1.3 meters the pilot can deploy ahighly complex system of hydro-

foils integrated intothe sleek body ofthe “Splash.” TheFormula-1 typerear spoiler rotates180 degrees downand comes to restbelow the“Splash.” To theleft and right of thehigh side walls ofthe cockpit two hy-drofoils integratedinto the outsideskin rotate 90 de-grees to point

straight down before un-folding into their liftingV shape.

The angle of attack ofeach hydrofoil can be ad-justed individually bythe pilot to account forthe various operatingstates. Already at lowspeeds the vehicle beginsto lift itself out of the wa-ter. The fully suspended positioncan be reached at speeds as low as30 km/h (about 17 knots), andattains a speed of approx. 45 knots.

“Splash” is powered by an environ-mentally friendly bivalent turbo-charged natural-gas engine. Naturalgas is an extremely clean-burningfuel that consists almost entirely ofmethane with near-zero sulfur con-tent. The “Splash” is the world’sfirst amphibious vehicle to beequipped with this future-orientedengine technology.

Street performance is nothing to beashamed of: The 825 kg quick-change artist accelerates in about5.9 seconds to 100 km/h and reachesa top speed of 200 km/h. The sleeklines of the “Splash” draw attentionat first glance.

The interior of the “Splash” clearlypays tribute to its maritime qualities.Lightweight and waterproof plasticscover the tubular frame and theergonomically shaped plastic seats.The small sport steering wheel isperfect for the agile handling char-acteristics of the lively and highlymaneuverable “Splash.” A numberof chrome-plated shift knobs, whichgovern the amphibious functions

and the angle of attack of the hydro-foils, exude an atmosphere reminis-cent of an airplane cockpit.It should be noted that there is noprice set for the Rinspeed “Splash”.It is not for sale.

Underwater View of Splash “Hullborne”

Splash Ready to Roll

IHS Summer 2004

SEASCAPE CATAMARAN HYDROFOIL

YACHT


(Extracted, by permission from

PR website)

Seascape Marine Industries hasbeen awarded the contract tobuild the first ever catamaran hy-

drofoil motor yacht of its size andtype in the Pacific Northwest.Apollonio Naval Architecture andMarine Engineering of Bellingham,WA designed thehigh-speed 67’ motoryacht. The Seascapeyard is located about a90-minute drive awayon the Fraser River inMaple Ridge, a suburbof Vancouver, BritishColumbia, Canada.

The 67’, a fibreglass composite jetboat with twin 1500 hp engines, willhave a maximum speed of 45 knots atnear empty displacement, with acruising speed of 35 knots. The hullsand decks are designed to AmericanBureau of Shipping (ABS)high-speed craft guide, with 1”Core-Cell A550 or 600 hull bottomand 1” Core-Cell A500 sides. Twostainless steel hydrofoils with verticalstruts at center will be installed be-tween inner chines.

“Seascape’s success in securing thisproject demonstrates our ability towork with designers and owners todevelop advanced yachts that staywithin their budget requirements,”says company President Julie James.“This ability flows directly from ourteam members’ long experience inboat design and building.”

Sesacape’s strengths are its high qual-ity work – especially its outstandingfinishing and excellent fibreglass

work — and professional approach,says Apollonio. “I have worked withmany of Seascape’s staff when theywere with other yards, so I have greatconfidence in the yard – they reallyknow what they’re doing and theyhave catamaran experience,” he says

The pilothouse features include joy-stick control, weather-tight port andstarboard doors and a corner com-puter station aft to port.

The 67’ HYDROFOIL CAT speci-fications are as follows:

LOA: 67’5”;Beam (Molded): 26’6”Draft (Full load): 3’9”Empty (Dry Wt.) Displacement:99,000 lbs.Full Load Displ.: 123,000 lbs.Max Speed at Near Empty Dis-placement: 45 knots +/-Cruise Speed, avg. at max con’tpower: 35knotsFuel capacity 2,300 U.S. Gal.Freshwater capacity: 300 U.S. gal.Power: Twin MAN 2842 LE 409rated 1500 hpGenerators: (2) 2KW 120/240 VAC60 HZ Northern LightsConstruction: Fiberglass Composite

For more information, contact JulieJames Email:[email protected]

[Ed Note: Unfortunately, at this writ-ing, a picture of the foil system is notavailable.]

(Extracted from Work Boat

World, June 2003, Page 39 and

April 2004, Page 24)

The past year has been a busy oneat the offices of Morrelli &Melvin Design and Engineering

based in Newport Beach, California.

This leading yacht design and engi-neering firm has a diverse portfolioof projects, many of which arehigh-performance multihulls. In ad-dition to designing record-breakingsailing catamarans, cruising catama-rans, power catamaran yachts, andeven the occasional monohull, overhalf of their work involves the designof commercial vessels.

Amongst the several commercialvessel and power catamaran projectson the drawing board or launched inthe past year, there was a 15 metrecomposite foil-assisted catamaranexpedition vessel. A HYSUCAT(Hydrofoil Supported Catamaran)foil system designed by ProfessorGunter Hoppe will enable thislong-range excursion vessel to main-tain high speeds over long distanceswithout refueling. Weight will bekept to a minimum by incorporatingadvanced composites and by usingthe latest-technology diesel engines.Advanced propeller design will in-crease fuel economy and reduce fuel

MORRELLI & MELVIN ARE ON THE

MOVE


MORRELLI & MELVIN



weight. This will be a multipurposevessel to be used for record passagemaking, third world river explorationand humanitarian aid.

Morrelli & Melvin also have twoother foil assisted catamarans underconstruction that incorporate theirunique hydrofoil system.

After designing over forty power cat-amarans, Morrelli & Melvin have de-veloped high-speed displacement andplanning catamaran hull shapes opti-mised for a wide range of applica-tions.

Another area of expansion has beenthe incorporation of hydrofoils onseveral existing Morrelli & Melvincatamaran designs. Morrelli &Melvin recently undertook a two-yeartesting program to analyse foil de-sign. Consequently, a unique andhighly efficient hydrofoil system wasdeveloped and is now offered onsome of the new designs.

For further information contact:Morrelli & Melvin, USA.

PH: +1 949 723 7640, FX: +1 949723 7645,

Email: [email protected]

Web: www.morrellimelvin.com

(Extract from “Work Boat World”

September 2003, ‘Aft Lines’ col-

umn, page 83. Author unknown.)

Hydrofoils, like those digital di-ary things, are something I’venever really been able to decide

whether I like or not. They certainly

TO FOIL OR NOT TO FOIL

look flashy, and the efficiency bene-fits appear great on paper but in theback of my mind there’s always beenthis nagging doubt about the upfrontcost and just how operator friendlythey really are. (For some reasonwhenever I think about these issuesI’m reminded of the thoughts thatwent through my mind in the hoursbefore my wedding.)

Over the last couple of months Ithought the pendulum had finallyswung in favour of foils, primarilybecause they seemed to be havingsomewhat of a renaissance.

First, one of my buddies from Viet-nam (not the war; he lives there)called me up to say he’d heard thatone of the local shipyards was build-ing a hydrofoil ferry to a Russian de-sign and did I want him to organise aseat on the sea trials for me. While Ipolitely declined the offer - no disre-spect to those involved in the pro-ject-I’m just a conservative type whowould rather be left in the dark agesthan test something new. The kidsconsider that I am most successful inthis regard.

The news from the East did get methinking, though, that there must stillbe some merit in hydrofoils, eventhough shipyards have had so manyyears to come up with somethingbetter. That thought moved from theback to the front of my mind more re-cently when I read that another ferryservice between Fukuoka, Japan andPusan in Korea would be making useof a hydrofoil. This is a rough stretchof sea that has turned passengers onother, larger and more modern butsurface borne fast craft decidedlygreen so the apparent success of thefoil-borne ships indicates they stillhave a role.

This was virtually confirmed in mymind when rumours started to circu-late about a new order emanatingfrom Italy for either four or six newhydrofoils (depending on who youbelieve). In fact, I was at the stage ofmarching down the aisle and confirm-ing my vows to the maritime world’swinged wonders.

I should have remembered, however,that no matter how blissful thingsseem, for every better there is a worse,and for every health there is sickness.Along they came with a couple ofnasty accidents that showed that fly-ing above the water is not alwaysplain sailing.

On July 21, one of the numerous hy-drofoils operating in Greece crashedinto rocks while travelling at about 25knots, not surprisingly injuring anumber of those onboard. While it isalmost certainly yet another case ofhuman error, in my mind I can’t helpbut think that rapidly going fromfoil-borne to rock-borne has to beworse on passengers than a groundingfrom the same speed on a surfacecraft.

Close encounters with rocks should,clearly, not be part of any navigationalplan but every master that I have evermet expects to encounter waves - itdoesn’t take a PhD in hydrodynamicsto work that out. So, I find it ratherworrying that 22 people were injuredwhen, to quote news reports, “a hy-drofoil travelling from Hong Kong toMacau hit a large wave.”

Admittedly a typhoon had passedthrough that had resulted in ferry ser-vices being suspended. Clearly it hadbeen determined that it was safe fortravel to resume but the 227 passen-gers on the hydrofoil would presum-

IHS Summer 2004

HIGH FLYING BANANA


TO FOIL OR NOT TO FOIL


ably conclude otherwise after havingtheir trip so rudely interrupted.

The problem in this case, as in others,was that the ferry came off its foilswhen it hit the wave. The question inmy mind is what would have been theoutcome of a monohull or catamarantravelling at the same speed and hit-ting the same wave? I’m not sure, butmy gut feeling is that it wouldn’t havebeen three people in hospital withbroken bones and/or concussion.

The upshot is that I’m back to gettingthose pre-nuptial doubts wheneverthe hydrofoil question is asked.

[Ed Note: This article was includedin this issue of the IHS Newsletter topresent another view. However, theeditor has no doubt that the damageand injuries mentioned above wouldNOT have been less severe for a com-parable dispacement hullform. Fromall indications that we have seen, Hy-drofoils ARE NOT a dying breed!!]

UPDATE ON MANU WAI

By Garry Fry, IHS Member

There is some news on Manu Wai,looks like she will be relocated toPhuket, Thailand to operate

alongside the two RHS 70’s ex RedFunnel. I intend to go with her andwork the high season there for 6months each year and return to Aus-tralia in the low season. The companythere, Kontiki Dive, have a goodbusiness and the hydrofoils are prov-ing to be very popular. We have yet toenter into a business arrangement butthe only thing holding us back is thecost to transport Manu Wai to Thai-land and refit prior to service.

Kontiki is preparing a prospectusfrom which we hope to attract an in-vestor to come up with the money re-quired. Would rather send her up asdeck cargo due to the political cli-mate and risk of encounters with pi-rates but first quote is very high,about $90,000 Australian from Syd-ney. Part of that being removal offoils and shafting and reassembly atother end.We estimate fuel cost ofapprox $30,000 to deliver under ownpower so that option looks attractivealthough money will have to be spenton the vessel by way of antifouldocking and other work to make fitfor the voyage.

The plan is to run Manu Wai fromPatong to the Phi Phi Islands, 30nm,and the RHS 70’s will continue to runto the Similan Islands from Patong,55nm, and Kao Lak, 40nm, respec-tively. Am about to burn CD of ManuWai showing work in progress andearlier photos from purchase in 1995from New Zealand and recent Thai-land photos.

(By Ray Vellinga, IHS Member)

Surf’s not up? No problem, Dude.Not if your surfboard has a motorand hydrofoils.

That’s Hyfybe, a hot new hydrofoilidea out of Southern California.Hyfybe, High Flying Banana, is actu-ally a wind-surfer board fitted withan 8 HP long shaft outboard motor.

Ninety percent of the weight is sup-ported in flight by a carbon fiber &epoxy composite foil mounted be-

hind the pilot and ahead of the motor.It is surface piercing for roll stability.

At the bow are two aluminum foilswelded to a variable incidence strut.The lower foil is submerged 29” be-low the bow and provides 5% of lift.This has an extruded Clark-Y sectionand operates deep enough to avoidventilation. The second bow foil isplaced 13” higher on the same strutand provides the balance of lift. It op-erates in a constant state of ventilationand is lightly loaded to bounce alongthe surface. Its machine- milledcross-section is a 10% thick wedgewith the sharp edge forward. It has 27degrees of dihedral to soften the ride.

Heave at the bow is manuallytrimmed through an aircraft-type con-trol stick. The stick is pushed forwardor back to reduce or increase the angle

The High Flying Banana Foils





of the IHS website.


Disclaimer






HYFYBE


of incidence of the two-tiered frontfoils.

Flying technique involves accelerat-ing the craft to take-off speed, about6.5 mph with the stick far forward.The stick is gingerly brought backand then relaxed to bring the upperfront foil to the surface. This in-creases the angle of attack on the rearfoil, and it rises to find its correctlevel. The stick is held relativelysteady during stable flight. Howeverany pitch disturbance requires the pi-lot to respond quickly with the stickto prevent dramatic excursions. It’s agame of skill. The maximum speed isabout 10mph.

This is a wind-surfer that needs nei-ther wind nor surf. There are no plansto commercialize this just-for-funprototype.

Provided by Christof Schramm, IHSMember

This is a story about a hydrofoilconversion from the GermanDemocratic Republic from 1961

Normally foldboats and other boats,which could be taken apart to savespace, are not known for high speedsand hydrodynamical innovations. Butthe designers of the Mathias-Thesenshipyard in Wismar, GDR, did not ac-cept the technical restrictions in thiscategory of small crafts. In the late fif-ties they developed a conversion ofone of their products, the foldboat“Delphin 110”, that ride on surfacepiercing hydrofoils at speeds of 50km/h.

A FOLD BOAT AS A HYDROFOIL

The “Delphin 110” is a small lightweighted craft with a length of 4.8mand a width of 1.1m, that could carryabout 4 to 5 persons and has normallybeen driven by a 7.5 hp outboard en-gine. It has been built in a quite largenumber and has been used on theplenty of lakes in the North of the so-cialistic German Democratic Repub-lic. An important advantage was, thatthis craft could be taken apart into asmall package, which easily could bestowed on the roof of a car. Someused this boat for water skiing, but thespeed that could be obtained by thepoor engine has not satisfied more ad-vanced water skiers.

So some open-minded engineers ofthe shipyard developed a new versionusing hydrofoils, capable of running

foilborne at 50 km/h. The hydrofoilsystem was quite similar to manyother systems of this era. TwoV-shaped foils of a similar size havebeen installed under the fore ship andthe stern of the craft. Like the basicdesign this fast craft could also betaken apart easily.

A not often seen detail has been asmall vertical fin under the tip of thefoils, that helped to stabilize the di-rection and has been used to connectboth halves of each foil with bolts.

A lengthened outboard engine witheven 7.5 hp has delivered the power.On account of the lightweight and theshallow smooth waters on the lakesthe boat ran successfully and was ableto pull a water skier with even higherspeeds than it’s predecessor.

Unfortunately this conversion has notspread widely. So only a prototypehas been built. There is also only poorinformation available about this craft,taken from some articles in the news-papers of the socialist party SEDfrom 1961. For those, who are inter-ested to learn more about this littlehydrofoil is the website is:www.derpoly.privat.t-online.de

IHS Summer 2004


PHM MODEL KIT

By Felix Bustalo; Extracted from

Web Site:

steelnavy.com/wem_pegasus.htm

White Ensign Models appears tobe on a Cold War UnitedStates Navy kick recently. The

USS Pegasus kit is the third in thiscategory with a few more planned forfuture release. White Ensign hasearned a reputation for producinghigh quality resin kits and photo-etchdetail sets, so one can anticipate thatthis kit would meet thosebenchmarks. This is a very simple kitto build and is comprised of aone-piece resin main hull/superstruc-ture assembly and 9 white metalparts. A small photo-etched brass de-

tail set is also provided.

The main resin piece is well done andrequired practically no clean-up; justa little bit of sanding along the keel toremove some remnants of the castingblock. There is a very nice level of de-tail cast into the hull and superstruc-ture but I found one minor omission.The Pegasus class of boats had ventgrills on the either side of the super-structure towards the aft. My exam-ple had one on the starboard side butit was missing the one on the port sideof the superstructure. The grill thatwas present on the starboard side wasthe only detail not cleanly cast assome excess resin clogged up the grid

work. I correct the starboard vent andto add the missing port grill I usedsome generic radar grid from the GoldMedal Models 1/500 scale Naval Set,cut down to the correct size. In myopinion the generic grid from this setlooked more in-scale and could passfor the vent grills. When I surfed theNet looking for photographic refer-ences I came across a site with someconstruction images (since then theURL is no longer active). One photoon the Taurus clearly shows a pair ofstabilizers on the underside of the hullat the stern. This was overlooked inthe kit but in my spares box I hadsomething that would fit the bill. Thephoto-etch from the White EnsignModels HMS Nurton minehunter kithas a pair of rudders that are about thesame size and shape. Since I opted tobuy the waterline version of the kit, Idid not need them for that build. So Iutilized them here for the missing sta-bilizers. The white metal parts in-clude the 76mm Oto Melara gun, theHarpoon missile tubes, the main mastarray, the Mk. 94 GFCS radome, en-gine exhaust duct and the fore and aftfoils. The white metal parts were alsovery well cast and required very littlecleanup. All I had to do was removesome flash from the mast yards. Loca-tor holes are cast into the deck andhull for the turret, mast, exhaust ductand aft foil. This simplifies construc-tion and provides for a better bondwhen you glue the parts into place. Iwish that a locator hole was cast intothe hull for the fore foil. I drilled asmall hole into the bottom of the hulland into the top of the fore foil’s arm. Iglued a small bit of brass rod into thefoil and glued that into to the openingI made into the hull. The photo-etched brass set is beautifully donewith crisp relief etched details. The kitcontains the railings, radome supportlegs, 12 bollards, two Harpoon

launcher cradles, main mast brace andthe jackstaff. A brass etched name-plate is also provided which can beused to display your model. The rail-ings are all in pre-measured sections,which saves time and effort. The qual-ity of the photo-etch is up to the stan-dards that I expect from Peter Hall’sdesigns and White Ensign Models.

This model is a quick build and wouldtake only a few days if you were ableto work on it without interruption.Alas, I don’t normally have such goodfortune so I did a little here and a littlethere. Basically once I made correc-tions mentioned above and I paintedthe all of the parts and subassemblies,the kits just fell into place very easily.To mount the model I drilled twoholes along the keel to accommodatetwo lengths of 3/8-inch diameterbrass rod that I used as pedestals. Ipainted the model using mainlyTestors Model Masters paints al-though the kit’s color guide providesHumbrol reference numbers. I usedTestors Model Master Neutral Gray(#1725) for the hull, superstructure,deckhouses, gun and missile launch-ers Gunship Gray (#1723) for thedecks, Aluminum (#1781) for the hullbelow the waterline and foils and FlatBlack (#1749) for the boot topping.My photographic references showthat the radome and the whip antennawere painted white; for these I usedHumbrol Satin White (#130) becauseI have heard that this brand of whitepaint is much more resistant to yel-lowing. For the whip antenna I used alength of brass wire. Decals are notprovided with the kit, so I used a com-bination of sources to decorate themodel. For the larger hull numbers, Iused the Gold Medal Models Naval


PHM KIT


Ship Decals (Part Number 350-1D).For the “E” efficiency markings onthe turret and the smaller hull num-bers that appear aft I used a sheet thatDuane Fowler created for me when hestarted producing decals. For theship’s name on the transom, I createdmy own using a word processor, astandard HP laser printer and somecompatible decal paper.This kit was a fun and relatively easybuild of a very unique subject. Whilethere were some very minor flaws thatare easily corrected, it is an excellentkit. If you like modern United StatesNaval ships or small combatants, thenI would recommend you add this toyour collection. I purchased my kitmail order from Warshipbooks.combut you can also buy it directly fromWhite Ensign Models.

RC PHM-1 Pegasus

Iam in the process of undertaking

the construction of a 6’ RadioControlled PHM-1 Pegasus. My

father was a Chief on the first crew,and I stood on the pier as a 9 year oldkid on her first arrival to Key West. Iwould like to know if anyone has acopy of schematics, or technicaldrawings for her or the others. Dueto the fact that she’s gone and I’llnever see her fly again, I want tobuild one that will. Are there any-more out there. Feel free to contactme at: [email protected], T.D. Mehl

Hydrofoil ALBATROSS

Irecently received some inquiries

as to the status of the hydrofoil

ALBATROSS. However, in my usualprocrastinating manner, I deleted theemails before I could copy the ad-dresses of those who sent them. Myapologies on this. The ALBATROSSis still in Centereach, Long Island in arather neglected state. Still hoping tointerest a museum in adopting her.She was the only one of her class to bebuilt in Costa Mesa, CA. All the oth-ers were built in West Chester, PA.Wilson was supposed to build them attheir yard but according to HelmutKock, they did not have the experi-ence in welding aluminum so asub-contractor was used. Again myapologies on the belated response tothe inquiries. Robert Miller Email:[email protected]

MK 75 MOD 1 Gun System ISEA

Have been reading posted mes-sages on the bulletin board atyour site. I, too, spent lots of

time at MLSG, Key West on TDYperforming MK 75 CASREP repairsand ORDALT upgrades on thePHMs. Most of my days in doing sowere between 1982 and 1987. Theone name I noticed in the posted mes-sages that I recall is the one of BobAdams. He gave me some 76mmspent brass casings once when I wasthere to conduct a MK 75 change-outon the TAURUS. I’m still an engi-neer in the MK 75 ISEA Office whichhas always been here in Louisville,KY. Would appreciate hearing fromanyone that has some ‘good’ photosof the PHMs for our office. Thanksfor the Memories, Jerry R. Grasmick,EE, NSWC (alias Naval OrdnanceStation Louisvile; NOSL) MK 75ISEA, Code G41 DSN 989-5045

To: George Jenkins: I found yourarticle on the Web Site about thePHM acquisition program most in-formative. Your Article/Paper was

well written. A lot of myths about thePHM Program were clarified in yourpaper; exorbitant costs of manufac-ture, maintenance, etc. I had heardback in the mid ‘80s that Congressinitially was going to procure ~ 35 ofthis class and deploy them with BattleGroups; a PHM would be carried(cradled) by a host battle group ship.Then, the PHM program justfroze....Congress debated over thecompletion of PHM-6 USS GEMINI.I just wished that Congress and othershad not terminated the program. Theship class had so much potential;even in today’s world conflicts in theMid East region and for Close-In ar-eas of protection against the “smallboat” threat. Regards, JRG, Engi-neer,Code G41 MK 75 ISEA; JerryR. Grasmick;[email protected]

Supercavitating Spoiler

The Russians were apparently de-veloping torpedo designs thatoperated in a supercavitating

mode through the use of a particularnose shape that promoted a vapourcavity over the aft portion of the tor-pedo. This may have had a wedge orstep to trigger the cavity aft of thenose. Supramar AG in Switzerlandhas also been researching the use offoil profiles with a groove that pro-motes (or prevents?) supercavitatingflow. I don’t know if that was also in-tended to serve as a means of motioncontrol. Some information about thiswork is on the Supramar website:www.supramar.ch; Martin Grimm

Plainview Vet

Ifound this forum on a Google

search after I came across thePlainview’s hulk on a recent vaca-


INTERESTING MESSAGES

IHS Summer 2004


SAILOR’S PAGE

By Sam Bradfield, IHS Member

SCAT sailed the Miami-Nassau RaceMarch 19 and 20...her Maiden Race!It was a hundred and seventy fivemiles of crossing the Gulf Stream andbeating upwind hullborne except forthe last twenty five miles close reach-ing. The wind was 15 to 30 knotsgusting to 40. The seas were six tofourteen feet and short and steep...un-pleasant conditions for a first race fora foiler and crew.

A mixed fleet of 22 boats entered, 9multihulls and 13 monohulls. Onlyeight boats finished...two multihulls,catamaran Green Flash (DaveCalvert) and foiler SCAT (PhilipSteggall) and six monohulls. Themultihulls led the pack crossing thefinish line first and second, two hoursahead of the first monohull. Scat tookSecond Place in the race and beat thefirst finishing monohull by more thanan hour. The winning elapsed finishtime was 25 1/2 hours. We don’t havea writeup of the details of action inthe race itself as yet. The crew mem-bers, Steggall, McGarry, Caffee, andZwart are preparing tech notes for theproject use, but we don’t have them inpublishable form as yet.

SCAT came in second with very littledamage. She’s a tough boat with agood crew. Too bad the course wasdirectly upwind for 150 miles of therace. Next time I hope we’ll be fa-vored with more reaching (flying)wind angle than beating. SCAT de-serves a chance to show her speedflying!

SCAT UPDATE

By Martin Grimm, HIS Member

Ihad the pleasure of meeting the

small but dedicated group of West-ern Australian Moth sailers on

Sunday 25 May at the NedlandsYacht Club in Perth. A race had beenarranged as there had been no statechampionships over the previoussummer. With only light wind on theday, conditions were not favourablefor hydrofoil equipped moths. Insuch conditions it is difficult to be-come foilborne and consequently theadditional wetted surface area of thefoils simply creates more resistancethan a standard Moth.

Although Garth Ilett brought alonghis foils for ‘On the Prowl’ [refer toarticle in Spring 2003 NL], he de-cided to enter the race with a conven-

HYDROFOIL MOTH NEWS tional centreboard and rudder. BrettBurvill’s moth on the other hand wasbuilt to run only with hydrofoils andso he was not able to exchange thefoils for a centreboard. While theconventional moths had good runs,Brett was only able to becomefoilborne intermittently and wasslowed by the foils when the winddropped or the heading was unfa-vourable. The potential of the hydro-foils was however made veryapparent at the end of the last racewhen he was able to make a foilborneburst to the last mark. The accelera-tion of the boat as it became foilbornewas impressive and he rapidly gainedground on the moth leading him be-fore the mark was reached.

The original moth foiler built andsailed by Brett Burvill [refer toSpring 2000 NL] is now on display atthe Western Australian MaritimeMuseum in Fremantle where it sharespride of place with ‘Australia II’, the12m yacht which won the America’sCup in 1983. The attached photosshow this craft and its foils. Althoughthe moth is a developmental class in-tended to give as much freedom aspossible to allow the design to evolvefor higher performance, last year aruling was made that the laterallysplit foil arrangement would no lon-ger be permitted as this could be con-sidered as a multi-hull configuration.The bi-foiler arrangement as appliedon other moths where thecentreboard and rudder are replacedwith inverted T-foils remains permis-sible under the moth class rules andso this design path will undoubtedlysee further development effort.

Windrush Foiler Moth on Dis-

play in the Western Australian

Maritime Museum.


Based on the good performance al-ready demonstrated with ‘On theProwl’, John Ilett has been busy pro-ducing new carbon fibre foil units foran experienced moth sailor in Mel-bourne. These are of a similar ar-rangement as illustrated in the lastnewsletter however with minor re-finements in design and production.The foils are again fitted with flaps asdescribed previously and illustratedin the accompanying photo. John isable to manufacture both carbon fibrefoil sections and complete T-foil as-semblies in his workshop. More de-tails can be found at his website:http:/www.fastacraft.com

Courtesy of Sebastien Francois

(www.jellyfish-foiler.com)

In the Winter 2000-01 and Spring2001 newsletters, a review wasprovided of some of the past sail-

ing speed record holders. Since thattime, several new concepts haveevolved to challenge the sailingspeed record, and once again theseinclude hydrofoil-supported craft.

One such concept is the innovativeJellyfish Foiler. This hydrofoil sail-boat will be powered by a rigid kitedeveloping 870 kg (1900lb) thrust atfull speed. When foilborne, the hull

will fly some 80cm above the watersupported by two outrigger mountedJ-shaped foils and a T-foil ruddermounted aft of the hull. Flying tests ofthe Jellyfish Foiler while towed by amotorboat commenced in late 2000and were completed in the spring of2001. These tests demonstrated thatthe boat was able to fly in a stablemanner.The team has undertaken testing of

kite propulsion using a more conven-tional Hobie cat hull. Sebastien re-ports sailing under kite power is verystable and requires relatively littlewind strength.

The kite is supplied by KITECH, asurf kite manufacturer. For JellyfishFoiler, KITECH has produced an ex-tra strong kite with a 22m² wing areaintended to be able to fly in 20-30

JELLYFISH FOILER – KITE POWERED

HYDROFOIL CONCEPT FOR SAILING

SPEED RECORD

knot winds.The current absolute wa-ter sailing speed record holder is theYellow Pages Endeavour, whichachieved an average speed of 46.52knots over a 500m course on 26 Oct.1993. The objective for JellyfishFoiler is to initially break the 50-knotbarrier with a subsequent target of 54knots (or 100 km/h).

While the project was on hold during

the Canadian winter (rivers are frozenin Montreal during that time),Sebastien is working on a new hydro-foil concept and was hoping to testthis towards the end of April. The in-tention is to set-up the foil systemwhile using an engine for propulsion,then to commence testing under kitepower.

Work is also underway on the devel-opment of a kite autopilot and elec-tronic measurement equipment hasbeen fitted to the craft.New teammembers are sought to help with fur-ther development of this interestingproject.

JEFOILER MOTH


IHS Summer 2004






WEB BENEFIT




quest your link, contact William

White, IHS Home Page Editor at

[email protected]

Welcome New Members



2001-2004 2002-2005 2003-2006

Sumi Arima Jerry Gore Mark R. Bebar

Malin Dixon Jim King William Hockberger

John R. Meyer Ken Spaulding George Jenkins

William White John Monk Dennis Clark

signed the TSM bow seal for theSES-200. He has authored andco-authored numerous papers andreports on AMVs including hydro-foils. At DTMB he was Chief Engi-neer of the LCC Project, responsiblefor the design, construction and ini-tial operation of the Navy’s $125MLarge Cavitation Channel, theworld’s largest variable-pressurewater tunnel. He was later teamleader for the DTMB group design-ing submarine propulsors includingthe new Virginia Class. Currently heis working on propulsion, cavitationand frictional drag reduction prob-lems at DTMB. He is an enthusiastfor the history of AMVs and test fa-cilities.

Adam Mendel – Adam is a highschool student from Atlanta, GAwho became interested in hydro-foils while researching boat build-ing on the internet. He intends tobuild a small experimental hydro-foil within the next year and hopesto achieve speeds of 30 - 40 knots oncalm water. Adam is always inter-ested in learning about new ideasand concepts, and plans to major inindustrial design in college.

Marcelo Paredes – Marcelo is aNavy Officer from Ecuador. Cur-rently he is studying Naval Engi-neering in the ESPOL University inGuayaquil, Ecuador. In one year hewill get a Bachelor Degree but the

prerequisite is to present a thesis orfinal project. Marcelo feels that Ad-vance Marine Vehicles is the wave ofthe future for maritime transport. Forhis thesis he wants to prepare a Pre-liminary Design of patrol craft. He iscertain he will find the right peoplewho could help him with his work.Marcelo hopes to make a contribu-tion with his work in the Society.

Max Runyan - Max has been a waterperson his whole life. From motordriven to wind driven to individualperson driven water craft of anykind, Max has always been inter-ested in learning more about howthey work. For the past 18 years Maxhas been pursuing a research and de-velopment career in the aerospaceindustry applying advanced metaljoining technology to the next gener-ation of aircraft designs. The combi-nation of Max’s research anddevelopment aerospace backgroundand his love for water vehicle activ-ity has lead him to become interestedin hydrofoil development both pastand present. Max reports that theIHS has been a wonderful sourceof hydrofoil history and informationand he looks forward to receiving hisnext newsletter with information onthe latest hydrofoil developments.

tion. As a member of the last activecrew (Operations Specialist) I wasshocked when I sighted the instantlyrecognizable hulk while driving westalong the Columbia river enroute tothe Oregon coast. I pulled the carover and confirmed that it was thePlainview. I was able to climb up thetail strut mount and board the ship. Itis in sad shape. There are holes andtears in the aluminum hull and super-structure. The tail foil is lying on themudflats aft of the ship. What a sadend to a once marvel of engineering.Although the Plainview sufferedmany problems, when it was fullyoperational it was an amazing ride. Ipersonally can attest to experiencing65 knots as a member of the naviga-tion watch during one trail. It liter-ally flew. Michael Temple;[email protected]

INTERESTING MESSAGES


MIAMI-NASSAU FEEDER RACEAND RETURN - SCAT SHOWS

HER STUFFBy Sam Bradfield and Tom Haman, IHS Members

SCAT sailed the Miami-Nassau Feeder Race and return to Floridain March 2004. See the IHS Summer 2004 NL in the Sailor’sPage section. We didn’t sail the race, but Tom flew out to Nassau

to bring the boat back to Florida Institute of Technology. The returntrip is where SCAT really “showed her stuff”.

It’s hard for us to place a fair evaluation on the racecourse perfor-mance of SCAT and crew based on this one race. It was our first oceanrace and conditions were the worst possible: beating hullborne di-

WHERE ARE YOU INCYBERSPACE?!




your email has changed recently, let us

know your new email address! Thanks.

2005 DUES SOON









using PayPal. To pay by credit card please

go to the IHS membership page at

www.foils.org/member.htm and follow

the instructions.

See SCAT, Page 3

INSIDE THIS ISSUE

- President’s Column ------------ p. 2

- Welcome New Members ------ p. 2

- Recollections of Plainview ---- p. 4

- Flexible Propellers ------------- p. 6

- Rim-Driven Pod ---------------- p. 6

- RC Hydrofoil Models --------- p. 9

- Sailor’s Page ------------------ p. 10



Editor: John R. Meyer Autumn-2004 Sailing Editor: Martin Grimm

SCAT on Trials Before the Race

IHS Autumn 2004

PRESIDENT’S COLUMNThomas Bein – Tom heads up theMarine Division of the MaritimeApplied Physics Corporation. Hecame to MAPC after 25 years atNSWC in Annapolis where in hisearly days he worked on the devel-opment of the composite piping thatwas installed in some of the USNavy’s hydrofoils. He is currentlymanaging an R&D program to de-sign and fabricate a 35 ft unmannedhydrofoil that will be used to rapidlydeploy sensors used for ASW andASuW. The prototype vessel will bediesel powered using gear boxesmounted in the retractable struts todrive propellers. Launch is ex-pected in the Fall of ‘04.

Philip Bradley - Although his ca-reer for the last 20 years has been inhigh tech, Philip has always builtexperimental vehicles in his sparetime. Over the last 10 years he hasbuilt two hovercrafts and one gyro-copter (like a helicopter). He wasrecently introduced to hydrofoilsand was immediately capti-vated. He has read with interestmany of the IHS Q&A pages andlooks forward to his next projectthat he plans to start this Autumn.

John Budden – John is a softwarevalidation engineer for pharmaceu-tical control systems since the early1990’s, and before that a controlsystem programmer. His hobbyhowever, is aerodynamics whichhas developed into interest in sur-face effect craft (WIG) using a hy-drofoil to lift the craft clear of thesurface and allow the speed and rameffect to build up such that the foilslift clear of the water and can be re-


WELCOME NEW MEMBERS

To All Members,

At the June 2, 2004 Board of Di-rectors meeting, the voting bythe general membership for the

Board members to serve during2004-2007 was reviewed. Resultswere that Sumi Arima, Malin Dixon,John Meyer and William White werereelected to the Board for the years2004 through 2007. Election of offi-cers by the Board members was heldat the July 21, 2004 meeting. The fourincumbent officers, having indicatedtheir continuing willingness to serve,were unanimously re-elected: Presi-dent, John Meyer; Vice President,Mark Bebar; Treasurer, GeorgeJenkins; Secretary; Ken Spaulding.

During the June Board meeting, sev-eral “Dues and Other Financial Pol-icies” were adopted:

- Payment of Annual Dues. Annualdues are payable as of 1 January.Members who have not paid by 30July will have all membership privi-leges suspended until payment ismade. If no payment is made by 31December, the member will bedisenrolled. If the former member de-sires to rejoin the Society within twoyears of his disenrollment, he will beliable for back dues plus dues for theyear in which he rejoins. After twoyears, the former member will betreated as a new member, except that anew membership certificate will notbe issued.

- Student Memberships. Studentmemberships will increase from$2.50 to $10.00 effective immedi-ately. Student members who have

paid their dues in advance will be“grandfathered” at $2.50 per year inthe years for which they have paid.

- Members Joining During the Year.Dues paid by new members and re-ceived by IHS prior to 15 Novemberwill be credited to the year in whichpaid. Back issues of the Newsletterfor that year and other membershipbenefits will be provided at no cost ifrequested by the new member. Duesreceived from new members on 15November or later will be credited tothe following year, but all member-ship benefits remaining for the year inwhich paid (e.g., Winter Newsletter)will be provided to the new member.

- Sustaining Memberships. Sus-taining Members are corporations,companies institutions and other or-ganizations who wish to support thework of the Society. The namesand/or corporate logos of SustainingMembers will be prominently dis-played on the IHS website, Newslet-ter, and letterhead stationery.Additionally, links from the IHSwebsite to the Sustaining Member’swebsite will be provided. Once annu-ally, Sustaining Members may sub-mit for publication in the Newsletteran article (not to exceed 250 words)describing its corporate/institutionalactivity in the recent past and inten-tions for the future. Up to 12 employ-ees of the Sustaining Member may bedesignated as Regular Members. An-nual dues for Sustaining Memberswill be $250.

Best regards to all,

John R. Meyer, President

IHS Autumn 2004 Page 3

SCAT(Continued From Page 1)

rectly into the wind and steepchoppy seas for the first 125 miles tothe second mark; and, after round-ing, close reaching with “skim-ming” and some flying the last 50miles to the finish line in NassauHarbor. SCAT made up an hour onthe lead catamaran on this final legdespite having taken some damageto the foil control system riggingearly on in the race.

The crew were veteran sail boat rac-ers and three of the four are experi-enced foiler (RAVE) racers. But weall know that ocean conditions aremore demanding and that racing asail rig “power plant” on this verystable platform plus managing a lift-ing foil system for racing is most de-manding at our present level ofexpertise. It was the first race on afoiler for the skipper (PhilipSteggall). It was also the first off-shore race for the foiler sailors.Mike McGarry made good use ofthe GPS data in recording details of

the race and we hope to benefit fromthose in future efforts. At present,we are repairing the damage to thefoil system controls including over-hauling the main foil incidence con-trol hydraulics and latching as wellas the tail foil rudder box. We arecompleting the Raymarine velocityperformance instrument system.We’re doing this by adding a digitalcompass masthead mounted mastrotation instrument that was devel-oped in the Ocean Engineering De-partment of Florida Institute ofTechnology with Hydrosail, Inc.sponsorship.

The return trip presents a fairer,broader view of the boat’s capabil-ity as a lifting hydrofoil equippedsailing trimaran performing foil-borne at speeds exceeding wind-speed as she was designed to do.The weather and sea conditions andlayout of the course to windward forthe FEEDER RACE to Nassauforced the boat to perform hullborne85% of the time for that first portionof the trip. The average boat speedfor the 175 mile course was 6 ½knots. Not a fair test for a foiler. Shedid well to finish second to a wellsailed high performance catamaranin that race where only a third of the

starters were able to finish. On the re-turn trip she achieved speeds of 20 to25 knots for appreciable stretches re-turning to Fort Pierce. She provedthat she can really live up to the name“SCAT”!

The Miami-Nassau Race was veryexpensive. I don’t think we’ll do the2005 STAR. That’s an upwind raceand based on what we just saw,SCAT’s hydrofoil sailing techniqueupwind needs additional work. Whatwe must work on is optimizing thetradeoffs between pinching and foot-ing to windward to maximize speedmade good to windward racing with-

out overstressing theboat. Note:“pinching”is steering at 40 to 45degrees heading to thewind; “footing ” is 55to 60 degrees headingto the wind.

We’ve decided to pur-sue our summer seriesof experiments in thegulf stream here in our“front yard”, so tospeak, until we’retruly “race-ready”. We

can get some “rough and ready”practice there. If we can get sponsor-ship we’d like to try a “downwind”run from New York to Lizard Point in2005 if this summer’s experience en-courages it. Lizard Point is in south-west Cornwall, England. It is thewesternmost point in England andtransatlantic races and/or time trialsare frequently run to and from thatvicinity from New York and othereast coast sailing sites. In our prac-tices we’ll be shooting for an averagespeed of at least 20 kts over long dis-tances.......Who knows?

*************

SCAT in Light Air Off Port

Canaveral

Photo by Mike McGarry on Return Trip from

Nassau to Fort Pierce, Florida

IHS Autumn 2004

RECOLLECTIONS OF THE PLAINVIEW


By Greg Bender, LCDR, USN(Ret.), IHS Member, USS Plainview(AGEH-1) Engineer Officer1975-1977

From the Long Beach, WA ChinookObserver, Wed. May 19, 2004 (withpermission):

Derelict Ship Being Scrapped. A

landmark along WA SR 401 will soon

be a thing of the past. The Giant Ex-

perimental Hydrofoil AGEH-1

(Plainview), at 200 feet, the world’s

largest aluminum ship when it was

launched in 1969, is being disman-

tled for scrap by its owners, the

Stambaugh family.

Iremember the day I first walked

aboard the USS PLAINVIEW

(AGEH-1). I had just completedSurface Warfare Officer School (Ba-sic) and was wearing the shoulderboards of an Ensign having receivedmy commission through the NavyEnlisted Scientific Education Pro-gram (NESEP) only six months ear-lier. As a Navy enlisted man in SanDiego some four years earlier I hadseen the USS Tucumcari and USSFlagstaff at the San Diego Naval Sta-tion. They were conducting local op-erations following their return fromVietnam. My curiosity had gotten thebetter of me, and I had asked for atour. The OIC of the Flagstaff re-warded my curiosity with a tour andpictures of the Flagstaff in operation.I was soon hooked on the newhigh-speed Navy and requested hy-drofoil duty as I prepared for my com-missioning. To my surprise, Ireceived orders to the USS

PLAINVIEW (AGEH-1), then theworld’s largest hydrofoil.

On the IHS website Bill Ellsworthdescribes the PLAINVIEW…

This 320-ton hydrofoil was charac-terized by its long, slender hull. Onemight wonder why there was no “A”on the hull of PLAINVIEW in viewof its “AGEH-1" designation. It turnsout that it is not customary to includethe ”A" on the hull of US Navy auxil-iary ships [AGEH stands for Auxil-iary General Experimental Hydro-foil].

The ship had a length of 212 feet andan extreme beam with foils down of70.8 feet. It attained foilborne speedsof over 50 knots from two GeneralElectric LM-1500 gas turbine en-gines driving two supercavitatingpropellers. Two Detroit Diesel en-gines drove propellers for low-speedhullborne operations.

[For additional information aboutPLAINVIEW, see the IHS website.]

I stepped aboard the PLAINVIEW inJune of 1975 at Todd Pacific Ship-yard expecting to be the Assistant En-gineer/Damage Control Assistant/Supply Officer. I soon found thatthere was no Assistant Engineer as-signed and the PLAINVIEW’s Engi-neer Officer, LT Mitch Berdinka, wasseparating from the Navy five dayslater and the PLAINVIEW’s vital bitsand pieces were spread across ToddShipyard, Puget Sound Naval Ship-yard and Boeing’s Renton Plant.PLAINVIEW’s OIC, LT Frank Hud-son, said not to worry too much abouta relieving letter, but to do anythingand everything I could to pickMitch’s brain before he left and figureout where everything was and whatcondition it was in. The XO, LTJGJoe Hugill, offered his encourage-ment.

PLAINVIEW was the victim ofon-again/off-again overhaul & con-version funding following a Decem-ber 1972 casualty to the starboardmain foil incidence control link whilethe ship was returning from openocean testing. In January 1973PLAINVIEW had begun an overhaulat Puget Sound, only to be sent toLockheed’s yard for minimal repairswhen Puget ran into capacity prob-lems. In May of 1974, PLAINVIEW

was towed to Todd’s Seattle yard tobegin what was to have been a twoyear overhaul and conversion.

With shepherding from the HydrofoilSpecial Trials Unit (HYSTU), we setabout helping Todd with the task offinding, fixing and installing all thebits of piping, machinery and electri-cal gear that made up the Navy’s larg-est hydrofoil. Corporate memory wasvital. Sumi Arima, Boeing’s DwainSorenson and PSNS Pipe Shop Fore-man Sib LeBeau had lived with thePLAINVIEW throughout its earlyyears. Their memory of where thingswere installed and how they workedwere crucial to getting it all back to-gether without too many pieces leftover. By the time we finally left theyards in January 1977, we only hadone sailor, RM1 Charlie Smoot, whohad ever been foilborne onPLAINVIEW.

During our final six months at Todd,ENCS George Hayes and I must haveworked about five and a half 18-hourdays a week monitoring productionwork, tracing systems, figuring outhow things were to function andtraining the crew for the start of oper-ations. At times we were remindedjust how unique the ship was. Thesetimes frequently came about when wewere trying to find some spare part or


PLAINVIEW(Continued From Previous Page )


other only to discover that the world’slast two widgets of a particular typewere either already installed else-where on PLAINVIEW or were theproperty of the Iraqi Air Force. Even-tually, the work package was com-plete, or at least as complete as couldbe expected, and the PLAINVIEW

was moved to PSNS for the start oftesting.

The Captain was determined thatPLAINVIEW would look and act likea “real ship” in as many ways as pos-sible from damage control andfirefighting to the daily routine andturned the crew loose to make it so.This inevitably caused concern withthe HYSTU folks as, in its earlier in-carnation, the ship had been terriblysensitive to weight and LCG. Previ-ously, everything that went aboardwas weighed and its destinationlogged. PLAINVIEW’s newfound ca-pability to fly at greater displace-ments allowed us to treatPLAINVIEW more like a ship and lesslike an aircraft. Although on one oc-casion I can recall it behaving verymuch like an aircraft. We were testingthe autopilot’s high-speed taxi modeand were at about 45 knots hullborneon the turbines with struts down whenwe flew right out of the water. Thefolks at Draper Labs who built the au-topilot had made a little mistake in the

algorithms. This had the effect of set-ting the foils to zero degrees inci-dence with respect to the baseline.The foils still had some lift at this an-gle and the large forward struts hadmore than the tail strut. As the bowstarted to come up, this increased theangle of attack and things progressedquickly. I was on the bridge and re-member thinking, “How are you sup-posed to see where you are goingwhen you can’t see over the bow?”The instrumentation showed that wewere trimmed about 11 degreesbow-up when the main foils left thewater and the turbines oversped andshut down. I remember hearing theturbines trip off the line then remem-ber falling. Fortunately, the main foilsre-wetted and regained lift at aboutthe same time. Other than a type-writer that committed suicide, I don’trecall anyone being injured. I thinkwe finally figured out that the mainfoils had been about 4 feet out of the

water at the apogee of our flight.

We eventually got most of the bugsworked out, and PLAINVIEW beganconducting fairly regular test flightsin Puget Sound. We were invited tovisit the Canadian naval base atEsquimalt near Victoria, British Co-lumbia for Canadian Armed ForcesDay and Victoria Day in the summerof 1977. PLAINVIEW performedflawlessly and decked in signal flags

and with orange and black stripedstruts retracted was the center of curi-osity for thousands of visitors to thebase.

I left PLAINVIEW that summer formy next duty station, and was relievedby LTJG Bob Butherus. Apparentlymy turnover to him was less disheart-ening than that which I received fromMitch Berdinka, because Bob fol-lowed me to the USS ELLIOT

(DD-967) where he served as DamageControl Assistant and eventually re-lieved me as Main Propulsion Assis-tant. As PLAINVIEW’s final ChiefEngineer, Bob witnessed the undoingof all the long hours spent makingPLAINVIEW work every bit as well asits designers had hoped.

As Bill Ellsworth recounts…

Unfortunately, soon after emerging

from a program of deficiencies cor-

rection and returning to the trials pro-

gram with many successful

operations in its log, PLAINVIEW fell

victim to the Congressional budget

knife. She made her last foilborne

flight on 17 July 1978, ending with a

total of 268 foilborne hours and with-

out ever being tested to the limits of

her rough water capability. The ship

was officially inactivated on 22 Sep-

tember 1978 and towed to the inactive

fleet at Bremerton WA. In May of

1979, the hull (less the struts and foils,

gas turbines, and other special equip-

ment) was sold to a private party for

the sum of $128,000. The engines,

foils, and transmissions were retained

by the Navy for possible use on an-

other prototype hydrofoil or another

advanced naval vehicle.

Long after my having left thePLAINVIEW, Dwain Sorenson sentme a picture of the ship on the Astoria

Plainview and High Point

USS Plainview (AGEH-1) Under-

way in Puget Sound

IHS Autumn 2004


PLAINVIEW(Continued From Previous Page )

mudflats. I had it framed and used tokeep it over my desk at NAVSEAalong with a photo of the shipfoilborne with Mt. Rainier in thebackground. People would ask mewhy I had a picture of a derelict ves-sel. I used to explain that the two pho-tos were the same ship, but in the firstphoto we hadn’t yet run out of imagi-nation.

Ex-USS Plainview on Mudflats

CARDEROCK DIVISION TO STUDYFLEXIBLE PROPELLER BLADES

By Richard Szwerc and Ki-HanKim

(Excerpted from NSWCCD Wave-

lengths, April 2004, by permission)

The Propulsion and Fluid SystemsDivision at the naval SurfaceWarfare Center, Carderock Divi-

sion (NSWCCD) is beginning athree- year program to determine themerits of composite marine propel-lers with adaptive blade pitch (flexi-ble blades) for Navy ships. TheDepartment of Defense ComparativeTesting Office is funding this pro-gram through the Foreign Compara-tive Testing (FCT) program.

Over the duration of the program, thehydrodynamic performance of multi-ple propellers will be tested in theCarderock towing tanks, the 36" wa-ter tunnel, the Large Cavitation

Channel, and at sea on an operationalvessel. Large blades, includingblades for a 25’ diameter propeller,will be built and fatigue tested at theUniversity of Rostock (Rostock, Ger-many) and at the United States NavalAcademy. At the conclusion of theprogram, the Navy will have experi-ence designing and insight into themanufacturing of flexible compositepropeller blades and will have thetechnical basis for providing recom-mendations to an acquisition officefor procurement strategies.

The propellers will all be designed byNSWCD and built by the Germancompany A.I.R. Fertigung-Tech-nologie GmbH in Rostock. AIR hasbeen in business for more than 10years designing and building carbonfiber composite propellers, includingpitch-adapting or flexible propellers.They have built more than 400 shipsets. While the principal users ofthese propellers have been megayacht owners, two navies have alsopurchased large propellers from AIR.Most propellers constructed havebeen the rigid design and range insize up to 13 ft. in diameter, but thecompany’s latest product is the flexi-ble, or pitch-adapting propeller.

In the pitch-adapting design, theblade pitch angle is allowed to adaptto optimize propeller performanceunder operational loads by taking ad-vantage of the ability to create direc-tion- dependent stiffness in the bladesthrough the use of fiber orientation.For example, if the leading edge is

At the conclusion of the

program, the Navy will have

experience designing and

insight into the manufactur-

ing of flexible composite

propeller blades.

stiffer than the trailing edge, the bladewill tend to twist (or change pitch),rather than bend uniformly as the pro-peller rotates. Designed correctly, thispitch change can reduce cavitationnoise and vibration and increase hy-drodynamic efficiency.

One innovation that is planned for themodel propeller testing is to incorpo-rate fiber optic strain gauges into theblades beneath the outer layer of fi-bers. With these gauges, the engineersat the Center will measure the bladestrains as the blades rotate ahead andin reverse, including the crash-backcondition. The strain will be com-pared against predicted levels to vali-date prediction codes and will be usedto estimate the service life of the pro-pellers. Some of the work with the fi-ber optic strain gauges will beperformed jointly with NRL and willbe funded by the ONR NICOP (NavalInternational Cooperative Opportu-nities in Science & Technology Pro-gram) project managed by Dr. Ki-HanKim.

RIM~DRIVEN POD PROMISES RELI-

ABILITY AND HIGH SPEEDS

(From Marine Propulsion June 04)

By David Foxwell

General Dynamics Electric Boatis developing a new type ofrim-driven propulsor pod which

it believes is inherently more flexible,reliable and maintainable than a con-ventional hub-driven poddedpropulsor, and better suited to appli-cations on fast ships.

Podded propulsors are widely used ina variety of applications, most nota-





of the IHS website.


Disclaimer






RIM~DRIVEN POD(Continued From Previous Page )

ble on cruise ships, and provide a highlevel of design flexibility, increasedpayload, improved efficiency and en-hanced maneuvering.

Offering the opportunity to eliminatelong shaft lines and sensitive bearingalignments, and significantly reducenoise and vibration on board, podshave proved popular with ship-own-ers, but the first generation of podshave also suffered from reliabilityproblems. Moreover, although highlyflexible, the speed achievable withfirst generation hub-driven pods islimited - primarily due to cavitation,but also due to pod size.

Under development for a number ofyears, but rarely described outsidespecialized technical conferences,the rim-driven propulsor pod thatGeneral Dynamics Electric Boat isdeveloping in the USA is, the com-pany believes, intrinsically more reli-able than hub-driven pods, allowingfor greater optimization of each ele-ment of the system, and capable ofsupporting higher ship speeds.

The rim-driven propulsor pod con-sists of a ducted, multi-blade rowpropulsor with a permanent - magnetradial - flux- motor rotor mounted onthe tips of the propulsor blades, andthe motor stator mounted within theduct of the propulsor.

Both the motor rotor and stator areseparately ‘canned’, which allows

them to be fully immersed in seawa-ter, with seawater in the gap betweenthem - hence the rim-drive does notrequire a rotating seal, said Bill VanBlarcom, who is a principal engineerat General Dynamics Electric Boat,involved in advanced concept devel-opment and evaluation of integratedelectric power/propulsion systemcomponents. The rotor shaft andbearings are housed in a relativelysmall hub, which is free flooding andsupported by a set of downstreamstator blades. The stator blades alsotransmit thrust from the rotor as wellas recover swirl energy from the ro-tating blades.

The key features that distinguish arim-driven pod (RDP) propulsorfrom a hub-driven pod (HDP) - whichhelp to make the concept inherentlymore reliable and maintainable - arethe hydrodynamics, motor, bearings,seals and clearances, Mr VanBlarcom said. “The RDP concepteliminates a number of design and op-erating liabilities that are inherent tohub-driven propulsors”. The rim-driven propulsor pod is strut-mounted to the hull via the aft portionof the duct.

“In a hub-driven propulsor, interac-tion occurs between the propeller andpod, resulting in vibration and cavita-tion. This does not happen in arim-driven propulsor pod, and theflow velocities over the exterior ofthe RDP duct and struts are low com-pared to that over the HDP, resultingin relatively low drag. In addition, the

presence of the rim on the rotatingblade row and the duct on the RDPmake for improved vibration and cav-itation performance compared to ahub-driven pod.”

The presence of the rim allows theblades to carry significant hydrody-namic loading at the tips without gen-erating tip vortices, Mr Van Blarcomsaid, and the duct ‘straightens’ non-uniformities in the flow ingested bythe propulsor due to currents, hullwake, and azimuthing, thus improv-ing vibration and cavitation perfor-mance. The duct also provides a levelof shielding of the propeller inducedhull unsteady pressures, improvinghull vibration.

Another advantage is that the RDPhas an inherently higher level of pro-tection against damage, comparedwith the open wheel blades of ahub-driven propulsor, the RDP rimand duct helping to protect the bladesfrom damage due to foreign objects.

The RDP is powered by a high powerdensity, low loss permanent magnet(PM) motor, which makes use ofGeneral Dynamics Electric Boat’spatented embedded magnet retentionsystem. The high power density of themotor - generally 40 to 100 per centgreater than the power density by vol-ume of wound field synchronous orinduction motors - is one of many fea-tures that facilitate the compact de-sign of the RDP and its high level ofhydrodynamic efficiency.


IHS Autumn 2004

RIM~DRIVEN POD(Continued From Previous Page )

Electric Boat says its embedded PMdesign is an order of magnitude morefault tolerant than a surface-mountedmagnet design. Impact resistance isprovided in part by the magnet loca-tion and retention method, and - be-cause the electrical gap between thestator and rotor is greater than typicalmotors - they can be separated suffi-ciently to allow the surfaces of eachto be canned and maintain a relativelylarge water gap between them. Thisalso enables an allowance for bearingwear, and provides more room forshock excursion.

The motor in question also has largeoperating temperature margins. Atfull load, an 18.5MW RDP has a nor-mal operating temperature of 114 de-grees C, but the insulation system isgood for continuous operation at 155degrees C. The motor rotor is locatedat a large diameter on the propellerrim, which produces higher torque atthe same power compared with locat-ing it at the propeller hub, and there-fore enables lower rpm. it also resultsin a shorter motor length and there-fore high power density, and low rpmin turn results in low relative veloci-ties, which in turn yields low dragand high efficiencies, and further en-ables high cavitation free speeds, andlow cavitation erosion.

When these features are combinedwith the RDP’s hydrodynamic attrib-

utes, it can enable an RDP to achievevery high cavitation-free speeds.

The cans for the stator and rotor incor-porate Electric Boat-developed andpatented composites and canningtechniques that provide a high integ-rity, corrosion-resistant barrier be-tween the surrounding sea water andthe motor stator and rotor with a lowlevel of electrical connectivity. MrVan Blarcom said the low electricalconductivity of the composites re-sulted in a reduction in electricallosses of some 6 per cent comparedwith metal cans, and the low level ofelectrical conductivity ensured thatthe varying magnetic field does not

set up eddy currents in the can itself.

The motor is cooled by the seawaterflowing past the pod, a mechanismthat is enabled by the high-efficiency,low-loss PM motor, waterflow pastthe duct outside diameter, which is aconducting surface for the stator thestrut configuration; this is integratedwith the duct to preclude stator hotspots, and the motor can, that allowsseawater flow through the mo-tor/stator gap for improved statorcooling.

Electric Boat’s PM motors are com-patible with pulse width modulation(PWM), which is offered by severalmanufacturers, including ABB,AsiRobicon, Toshiba and others, orpulse density modulated (PDM)drives. The company has followed a

step-by-step approach in the devel-opment of its PM motors, develop-ment having formally begun in 1991,but has also drawn on more than 100years of high performance motor de-sign and manufacturing experiencefor the US Navy.

Shaft/hub driven, non-submersiblePM motors have been produced andtested to date, including a 4.5MWmotor, which was produced in 2000and is now operating the US Navy’snew large-scale submarine test vehi-cle. Rim-drive submersible motorshave also been developed in the sameway, the largest to date being a1.6MW motor in an RDP that beguntesting in July 2003.

A number of additional designs havebeen completed or are currently un-der development for both low rpmshaft-driven and rim-driven PM mo-tors that range up to 30MW ElectricBoat shaft/hub driven 150kW and4.5MW PM motors have also beentested under a variety of off-designconditions, and their impact toler-ance demonstrated by shock testingto US military standards.

A 1.6MW RDP demonstrator com-pleted testing in March, and the sameunit is due to be installed on an as yetunidentified vessel in 2006, at whichtime tests up to full loading and formaneuvering will be conducted, andreliability data collected.

Cavitation testing to date has beenconducted at speeds of up to 26 knotsfor an RDP designed for a 25 knotmaximum speed. That testingshowed no damaging cavitation atthe highest speed tested, and the con-clusion from the tests is that RDPshave great potential for higher speedvessels.


INTERESTING MESSAGES ON THEBULLETIN BOARD

Yoichi Takahashi and Aimee Enghave been corresponding witheach other via the IHS Bulletin

Board on the subject of ra-dio-controlled (RC) hydrofoils. Youreditor has attempted to summarizetheir admirable efforts. They bothhave done some good work, partiallydescribed here along with pictures.

Yoichi Takahashi lives in Kyoto.Aimee is an architectural modelbuilder out of Portland and builds ar-chitectural models for customers inSeattle. In her spare time she has beenbuilding about a 6- foot model of thePHM. She is now in the process ofworking on the foils and waterjet sys-tem. Yoichi has been giving her ad-vice.

Yoichi has succeeded in constructingradio-controlled models of two hy-drofoil boats and would like othermodelers in the world to know aboutthem. One is ¼0 scale model of theBoeing Jetfoil. Control of these hy-drofoils uses small gyroscopes frommodel radio-controlled helicopters.Although the full-scale hydrofoil has

a waterjet for propulsion, he resortedto a propeller system for the model.

The second radio-controlled model isthe hydrofoil patrol guided missile ofthe Maritime Self Defense Force ofJapan (a version of the Sparviero).This hydrofoil is propelled using ascaled down version of the water jetpropulsion system. The water jetpump is a miniature version of theturbine pump of the full-size hydro-foil. Hydrofoil control is accom-plished using the gyroscopes formodel radio controlled helicopters.Both RC models are powered byelectric motors and a nickel-Cd 7.2volt battery. If anyone has a questionabout Yoichi’s excellent work, pleasecontact him by E-mail: YoichiTakahashi ([email protected])

Aimee hasn’t done a lot on the PHMmodel yet. She is working with anex-Boeing engineer, Cliff Shaw.When she mentioned this project tohim, he said he really wanted to dothe pump designs.

Cliff plans to test the pump and waterintakes prior to any hull construction.The proposed PHM model is scaledat ¼8 and they are trying to keep theweight down to 5 lbs.

[Your editor received word recentlythat IHS Member, Eugene Weinertpassed away in September 2003.Jerry Gore, and Bill White, IHSMembers, remember him well andhave written the following.]Gene Weinert was the senior gas tur-bine engineer at Philadelphia (OLDBOILER AND TURBINE LAB).Jerry Gore first made his acquain-tance working on the Naval InshoreWarfare Craft Program, later NavalSpecial Warfare Craft Program.Gene was the go-to-guy at Philadel-phia when we tested the completeTF-25 gas turbine and gear/shaft trainfor 1000 hours in the land-based testbed for Coastal Patrol InterdictionCraft (CPIC-X).Gene was likewise involved in everyGT project over his entire career and Irecollect that included the LM-2500land test bed and the USNS ship thatwas the seabed test ship forLM-2500—-also the TF-35’s andTF-40’s. Gene during the 70’s alsosupported the 3KSES program withtesting of the LM2500, FT-9 and Saltwater GT Demisting systems for theLCACs and other SES. We alsoworked on developing huge 50000 hpwater- brakes for their big GT test fa-cilities. Gene was a fine gentlemanwho was unafraid of progress andchange. It was a pleasure to workwith him during those early days.He was a valued professional contrib-utor as well as a consummate gentle-man in every way—he is one of thefew who helped get the US Navy outof steam and into gas turbines.He has authored/co-authored manypapers on gas turbines.We in the advanced ships communityowe Gene a lot—-he was one of us.

EUGENE WEINERT REMEMBERED

IHS Autumn 2004


SAILOR’S PAGE

By Dr. Ian Ward, Past PresidentIMCA, Developer of the first Din-ghy foiler, Bifoiler and UnifoilerMoths

Moths on Foils

To lift and glide silently and effort-lessly above the waves with ex-citing bursts of speed has long

been an ideal for those who dream!The potential has always been there,but practical reality has been lacking.It seems so simple to just place a foilunder the hull and go! yet in practice,it is far more complex.

The International Moth class is anideal forum for developing and eval-uating hydrofoils based dinghies.The class offers a forum of open de-sign rules and competitive interna-tional sailing. Moths are just 3.35mlong with 8.0sqm of sail and have nominimum weight limit. A competi-tive all-carbon boat weighs about 30kg and so is an ideal platform for foil-ing. Brett Burvill, Marc Pivac andJohn & Garth Ilett from Perth inWestern Australia have clearly dem-onstrated that Moths have sufficientpower to weight in order to fly onfoils. They have been demonstratedto be faster than displacement orplaning hulls when sailing in over 6knots of wind where they becomefoilborne. While these boats are cur-rently reaching speeds of 22 knots, itshould eventually be possible to sailat around 30-35 knots in 18-20 knotsof wind!

In spite of how difficult it may appearto balance on foils only mounted onthe centreboard and rudder, the foil ismuch wider and more stable than a

narrow displacement craft. HydrofoilMoths have the potential to be15-20% faster than the fastest currentskiffs, while the older Scow designscould easily double their speed withfoils fitted! It is now possible to out-perform many current skiff and cata-maran classes both upwind anddown.

The introduction of foils was one fur-ther step in the development of theclass as evident from the progressivelowering of their yardstick over thepast 75 years. I am sure there is evenmore to come! Unlike recent devel-opments in skiff classes where in-creased speed is primarily achievedwith larger boats, more powerful rigsand increased righting moment,Moths have made improvementsthrough increased efficiency and re-duced weight. Each small improve-ment results in higher speed, whichcreates higher apparent wind, so “thefaster you go, the faster you can go!”

Dinghy Foilers

“Dinghy Foilers” hardly dreamt ofuntil six years ago are now a reality.Winning a national sailing champion-ship on foils has never been achievedbefore in any International class.

Rohan Veal from Australia has shownin no uncertain terms that this is pos-sible with his resounding victory inthe 2003 Australian Moth Nationals,winning some 40 minute races by asmuch as 9 minutes!

Foiling sailboats have been aroundfor many years, but mastering din-ghies with only centerline foils is thelatest frontier. It was only in recentyears that foils have been applied tothe Moths class. Initial efforts werewith trifoil arrangements, but this ef-fectively categorized them asmultihulls which have since beenruled out.

It was not until 1998 that using onlycenterline foils placed on the rudderand centreboard was proven to be via-ble. This had probably not been at-tempted earlier simply because it wasnot thought to be workable. Such“bifoiler” arrangements exhibit quitedifferent behavior from trifoilers. I

will refer to this new breed of effi-cient sailboats as “Dinghy Foilers”.The efficiency of dinghy designs hasimproved considerably over the last75 years.

DEVELOPMENT OF DINGHY FOILERS

Ian Ward sailing the first ever “Bifoiler” Dinghy Foiler,

Sydney, November 1999.


[Readers are encouraged to see theunabridged version of this paper onthe IHS website at: www.foils.org/ ]

Moth & Dinghy Foiler Develop-

ments

Moth Dinghy Foiling has been devel-oping quietly over the past six years:

- An initial attempt at foiling by IanWard in 1998 was based on theTrifoiler “Longshot” which achieveda sailing speed record and formed thebasis of the Hobie Trifoiler. Whilefast in a breeze, the craft was complexand impractical to rig & launch,heavy and was also too stable, makingit boring to sail!

- Consequently the “Bifoiler” ar-rangement was developed and sailedin 1999, the first time any dinghy hadsailed on rudder and centreboard foilsalone. It addressed perceived limita-tions of the Trifoiler arrangement andproved the feasibility of sailing such afoil configuration.

- In 2000 Brett Burvill and MarcPivac independently introduced atrifoil Moth arrangement with surfacepiercing wing mounted foils. Theboat sailed well in varied conditionsand put foiling Moths on the map,winning heats in the Australian MothNationals that year. There were stillsome handling difficulties and prob-lems for rigging and launching. Un-derstanding that it was practical tofoil on just centerline mounted foilsand considering trifoiler moths to bemultihulls, the International MothClass Association voted to rule outthe latter configuration as being con-trary to the existing rule.

- In 2002 John and Garth Ilett took upthe considerable challenge and inde-pendently built their own bifoilerMoths that would satisfy the existingrule. They had solved significant con-trol problems and John continues toproduced bifoiler conversion kitsavailable from Fastacraft.

- With a set of Fastacraft foils, RohanVeal mastered bifoiler sailing tech-nique in a short time frame to place3

rdin the 2003 World Moth Champi-

onships and went on to convincinglywin the Australian National titles inJanuary 2004 with speeds some 20%faster than the current top displace-ment hull Moths.

The bifoiler arrangement has provenvery successful, now being intro-duced in Japan and the UK. The easewith which sailors have masteredsailing with foils suggests that theyare simpler to sail than a narrow skiffMoth in displacement mode. Thebifoiler also outperforms the originaltrifoil arrangement in terms of ease ofrigging, handling, speed around thecourse and race results.

Unifoilers

While “bifoilers” are the best solutionavailable to date, they are by nomeans the only or simplest solutionfor Dinghy Foilers. Another configu-ration under development is a“Unifoiler”, consisting of a singlelifting foil on the centreboard with acanard at the bow acting as a sensor,effectively using the boat itself as thesensor arm. This arrangement is evensimpler than a bifoiler, as the mainfoil does not require control flaps orsensor connections and no rudder foilor outrigger modification is requiredeither. With a small, retractable ca-nard foil at the bow, just slip thecentreboard foil in the casing and go!

The canard can be fixed or fitted witha sensor, surface running or im-mersed. Many variations are cur-rently being trialed. It may also beretracted due to its small size and thelight loads applied to it. The key ben-efits are simplicity, low cost and thatlift is generated by one foil working atmaximum efficiency. Extra foil sur-face area is available for lift-out but isreduced when the surface runningsensor canard foil leaves the water.

The Unifoiler concept was first ap-plied by Rich Miller to his foilingsailboard in California. To date onlyone dinghy has flown as a Unifoiler.This is a wingless scow Moth, whichis being used by Ian Ward as a testplatform for foiler developments.This photo illustrates what is possiblein just 6-7 knots of breeze!

The challenge now is to establish im-proved and simplified height andpitch control. Proving such designimprovements within a proper racingforum is the next step, made possibleby competing within the Moth class.

[To be continued in the Winter 2004issue of the IHS Newsletter.]

DINGHY FOILERS(Continued From Previous Page )

Ian Ward sailing the first ever

“Unifoiler”, a foiling Scow Moth,

Sydney, March 2004


2002-2005 2003-2006 2004-2007

Jerry Gore Mark R. Bebar Sumi Arima

James H. King William Hockberger Malin Dixon

Kenneth Spaulding George Jenkins John R. Meyer

John Monk Dennis Clark William White

Page 12 IHS Autumn 2004






NEW BENEFIT






[email protected]

WELCOME NEW MEMBERS(Continued From Page2)

tracted allowing the craft to fly inground effect. His eventual target isto build 1/6 scale model of this craft,but wants first to master the func-tion of the hydrofoils on a “clippedwing” version of the model withonly a 2.4M span. The main “T” hy-drofoil is based on the Moth foilsdesigned by Adam May and LyntonJenkins of Full Force Boats, Port-land, UK. This foil has beenre-enforced and profiled to take anall up weight of 190kg and a liftoff at 47Km/h. Construction is pro-gressing at a snail’s pace-qualityproblems with components andsome of the raw material the princi-pal culprits. The eventual aim is tolook for a configuration that willachieve 70 Km/hr cruise in 0.5Mwave height in ground effect at afraction of full thrust. The hydro-foils will be designed to achieve liftoff as close as possible to cruisepower.

Leonardo Lella – Leonardo is fromItaly where he works as anaero-maritime consultant, master inNautical Science, and a fully-ratedprofessional pilot both fixed wingand helicopters. He is very inter-ested in these fields, and acts also ashistorian, and when possible pub-lishes reports. Leonardo’s interestin hydrofoils comes from his earlyyears in Naples and his many tripsbetween Naples and Capri Island.

He has spent almost 40 years of hy-drofoil travel, during which time hehas flown on all kinds of Europeanhydrofoils. Now he is really afraidthat their slow progress and intro-duction of newer models has re-sulted in replacement by“inadequate catamarans and mono-hulls”. He has an interest in modelsof some hydrofoil types, and is in-terested in contacting others work-ing on hydrofoil models.

Robert Morazes - Bob comes fromNorwalk, CT where he joined theU.S. Navy and spent 4 years work-ing at NAS Pax River, MD, as a me-chanic. He stayed in the SouthernMD area after his discharge, andmanaged the St. Mary’s Co. Airport.Bob worked as a draftsman and en-gineer with Bendix Field Engi-neering. St Mary’s College of MDgranted him a BS in Math, after 8years of study. He then went to workfor Maritime Dynamics Inc. Whilethere he worked on vent valves, trimtabs, big and little T-foils, fixed finsand retractable ones. Bob alsoworked with the SES 200, for toomany of its iterations, many otherNorwegian and German SES’s, andmany of the Fast Ferry’s operatingin Europe. He is now employed byIsland Engineering where his firstjob was to work, yet again, on theold SES 200 being converted to Hy-

drofoil Small Waterplane AreaCraft (HYSWAC).

Terence Chung-Leung Yung -Terence graduated from The Chi-nese University of Hong Kong in1966 majoring in Mathematics withPhysics as a minor. He completed aCourse of Marine Navigation inWord-Wide Sea Training School. In1968 and served as a Deck Offi-cer on board various ships managedby World-Wide Shipping Group ofHK. During 1971-1973 he wasChief Officer on board various shipsowned by Cosmopolitan ShippingInc of New York. Since 1973Terence has served as Chief Offi-cer/Master aboard various hydro-foils, Boeing Jetfoils andHigh-Speed Cata- marans of ShunTak Shipping Co., and now calledShun Tak - China Travel Ship Man-agement Ltd after merger in 1999.At present Terence is a captain com-manding one of the Tricats.

TESTING TO START THIS FALL

ONR DEVELOPING TWO UNMANNED SEA

SURFACE VEHICLE PROTOTYPES

“This article was originally published in the July 26, 2004 edition ofInside the Navy. Reprinted with permission. Copyright Inside Wash-ington Publishers.”

The Office of Naval Research (ONR) is developing two unmannedsurface vehicle prototypes that it sees as future options for a com-mon Unmanned Surface Vehicle (USV) or a family of USVs.

A high-speed prototype and a low-speed prototype of the UnmannedSea Surface Vehicle (USSV) are expected to be in the water by this fall,said Scott Littlefield, director of the ship science and technology officeat ONR. Both will be about 11 meters long, allowing them to fit on aLittoral Combat Ship (LCS), he told Inside the Navy in an interviewJuly 21.

To reach speeds of more than 45 knots, the high-speed USSV will usehydrofoils, which will fold down when the vehicle is in the water andfold up when it is in stowage aboard a ship, he said. The low-speedUSSV will be optimized for towing arrays and other heavier payloads,traveling at 20 knots on a semi-planing monohull, he said. MaritimeApplied Physics in Baltimore is building both prototypes. The USSVeffort has about $9 million to build the vehicles, develop automated ca-pabilities and test them, Littlefield said.

When the two prototypes deliver in the fall, they will undergo basictesting to verify their speed, power, towing and sea-keeping abilities,he said. In early 2005, integration with payloads will begin. The LCSmissions are a top focus of the USSV effort, and the program executiveoffice for ships, which is in charge of LCS development, is workingwith ONR, he said. The high-speed USSV prototype is expected tohave payloads for anti-surface warfare, while the low-speed prototypeis expected to have payloads for mine warfare and anti-submarine war-

WHERE ARE YOU INCYBERSPACE?!




you are a member with email, let us know

your email address! Thank you.

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using PAYPAL. To pay by credit card

please go to the IHS membership page at

<http://www.foils.org/member.htm> and

follow the instructions.

See USSV, Page 3

INSIDE THIS ISSUE

- President’s Column ----------- p. 2

- Welcome New Members ----- p. 2

- Corsair Foiler 2200 ----------- p. 4

- Power Levels of Waterjets --- p. 5

- Tip Driven Impellers ---------- p. 7

- Bumpy Flying ------------------- p. 7

- Sailor’s Page ------------------- p. 10



Editor: John R. Meyer Winter-2004-2005 Sailing Editor: Martin Grimm

IHS Winter 2004-2005

PRESIDENT’S COLUMN


WELCOME NEW MEMBERS

William P. Carl - Bill Carl’s contri-bution to the hydrofoil communitystarted many years ago. During the1950’s, known as the "Decade of Ex-perimental Progress." The U.S. Navy,in its early development work, evalu-ated a hydrofoil configuration havingladder foils on the XCH-4 (Experi-mental Carl Hydrofoil No. 4). This16,500 pound, 53 foot craft, wasknown as the “Carl Boat”, after itsprincipal designer, William P. Carl. Ithad a seaplane-type hull supported bytwo sets of foils forward and a singlestrut and foil aft. Two 450 hp Prattand Whitney R-985 aircraft engineswith two-bladed controllable pitchpropellers 8 feet in diameter providedthe thrust to carry this craft to thehighest speeds since those achievedby Alexander Graham Bell’s HD-4.In 1953, its design speed of 65 mphwas exceeded in three to four footwaves. Later, a maximum speed of74.4 mph was recorded, which in1954 was a speed record for hydro-foils, exceeding Bell’s 1919 record of70.85 mph. The good performance ofthe XCH-4 encouraged U.S. Navy of-ficials to continue hydrofoil develop-ment. Shortly after final tests of theXCH-4, Bill Carl left J. H. Carl andSons to form his own company, Dy-namic Developments, Inc. Where heand R. Gilruth developed and pro-duced a hydrofoil kit for conversionof small runabouts. Grumman Air-craft Engineering Corp. purchased aninterest in the company and later ac-quired it as a base for their entry intothe hydrofoil market.

Thomas Haman –Tom is an ocean-ographer by trade and worked in theunderwater world, developing re-

Greetings to All IHS Members

and Best Wishes for the Holiday

Season.

Iwant to call to your attention to

several recent additions to the IHSWebsite:

1. IHS Webmaster, Bill White, hasposted the LCS (Littoral CombatShip) presentation on the BBS with alink to the IHS Web site where there isa downloadable copy of the presenta-tion. You can find it under the section:Hydrofoil Articles, Papers, Books

& Other References on the Homepage Site Directory. This presentationwas made at a joint meeting of theIHS and SNAME SD-5 in September,2004.

2. A very comprehensive paper onHydrofoil Ship Design by William C.O’Neill (IHS Member) can be foundin the section: Educational Pages

3. “The Quest for Speed at Sea”. In2003 IHS members Dennis Clark,William Ellsworth and John Meyerwere invited to write the feature arti-cle for the Technical Digest. This pub-lication is distributed every severalyears by the Naval Surface WarfareCenter, Carderock Division show-casing the work of the Division. In theOctober issue of the Center’sWavlengths, it stated, referring to therecently published Technical Digest :“In the feature article, The Quest for

Speed at Sea, Dennis Clark, WilliamEllsworth, and John Meyer, (formerDivision employees) showcase thehistory of the development of con-cepts and technologies to increase thespeed of naval vehicles and include apictorial timeline of high-speed naval

vehicles from 1900 to the present.”IHS has obtained permission to placethe article on its website. It can befound under section: Educational

Pages. All members are encouragedto view these 3 items.

We have noticed that inquiries on theIHS Bulletin Board are going unan-swered. All members are encouragedto check the BBS for information andquestions that you may be helpful inanswering. I encourage all membersto make an effort to visit the BBS atleast weekly and try to answer someof the questions, even if briefly. Wehave rightly tried to discourage directemail contact by steering people tothe BBS. That sets the stage for tech-nical discussions to be documented.So please follow through and provideresponses so the exchange of infor-mation will be documented and avail-able to all. At the same time, pleaseinvite non-members to join the IHSand become an official member of thehydrofoil community.

The Society continues to grow with32 new members added to the Mem-bership roles during 2004. You canview the Membership List by loggingonto the IHS website and put in theproper password. All IHS membershave been informed of this password.If you have been missed or forgot,please contact the webmaster. It is ad-visable for all to do this and check theinformation on the List. If it is incor-rect, please send changes to: SteveChorney: [email protected]

John R. MeyerPresident

IHS Winter 2004-2005 Page 3

USSV(Continued From Page 1)

fare. The USSV effort started a yearago and has been on a fast track, henoted.

“We felt there was an urgent need toget some prototypes out in the waterso we could start doing some exper-imentation and find out what worksand what doesn’t work,” Littlefieldsaid. “So everything we’ve donehas been on a fairly rapid timeframe.”

The USSV effort is not meant as a“one-size-fits-all” approach, but in-terfaces between the vehicle andpayloads are being designed forcommonality, he said. Some pay-loads, however, may not migratefrom one variant to another becausethe variant may not be optimized fora particular mission, he said.“We’re trying to do the maximumnumber of payloads on the mini-mum number of different hullforms,” he said. But whether thateventually will mean one hull ortwo hulls remains to be seen, headded.

ONR generally is focused on devel-oping the hull and propulsion forthe USSVs, he said. The programexecutive office for littoral andmine warfare, the Spartan USV pro-gram, and other agencies are con-tributing to the development of thepayloads, he said. Littlefield said hehas also had discussions with theDefense Advanced Research Pro-jects Agency (DARPA) about usinga potential payload called Holo-gram.

Still a concept and not yet a pro-gram, Hologram is an effort to dem-onstrate technologies for a“disruptive” approach to littoral

warfare, according to a statementDARPA spokeswoman Jan Walkerprovided to Inside the Navy. TheHologram effort will investigateand develop “Micro- AutonomousOcean Craft (MAOC) to spectrallyemulate platforms comprising U.S.maritime expeditionary forces,” shesaid. MAOC will operate in a net-worked environment, providing amultidimensional countermeasurefor naval forces, she said.

The main technical challenges inthe USSV effort are developing anautomated launch and recovery sys-tem and giving the vehicle autono-mous navigation capabilities inhigh sea states, Littlefield said. Thelaunch and recovery system will bea “very difficult problem” becausetwo vessels of different sizes wouldbe moving at different periods ofmotion, he said. The host ship mustgrapple the USSV without damag-ing each other, a task made moredifficult in heavy sea states, he said.The automation is necessary be-cause it is safer than having a sailormanually secure the USSV, henoted. In addition, the smaller crewsize of ships like LCS, with its com-plement of other offboard vehiclesrunning at high operational tempos,will also put a premium on auto-mated systems, he said. The Pro-gram Executive Office (PEO) forships is working with ONR on thelaunch and recovery problem, hesaid.

Autonomous navigation in choppywaves will be a challenge too. Cur-rent autonomous navigation pro-vides point-to-point commands,guiding the vessel in a straight line,Littlefield said. But a straight line isnot always the best course in highsea states, he pointed out. Rudderand throttle adjustments are neces-

sary to prevent the vessel from cap-sizing, as well as sensors to detectthe waves and algorithms to react tothem, he said. “Programming thatkind of behavior into an unmannedvehicle, I think, is going to be verychallenging,” he said.

The high-speed USSV prototypewill have more technical risk thanthe low-speed prototype, he said.Transferring power from thehigh-speed USSV’s diesel genera-tor down to the propellers on the hy-drofoils, which extend outwardfrom the hull, will be a challenge, hesaid. Another issue is getting thehydrofoils to fold up for stowage ona host ship, he said. The low-speedprototype will not have hydrofoils.

With the increasing attention beinggiven to unmanned aerial vehiclesand unmanned underwater vehi-cles, USVs may have been an“overlooked opportunity,” he said.Until the Spartan program, therewas not much investment in USVs,but it has been growing lately, hesaid. This spring, the Navy startedworking on its first USV masterplan, which is being led by the PEOfor littoral and mine warfare, hesaid. By contrast, the Navy issued aUUV master plan in 2000 and is al-ready updating it. Littlefield said hesees an important niche that USVscan fill, especially with the futureintroduction of LCS into the fleet.

“It’s incumbent on ONR to start get-ting into that game a little bit and tolook at where we should be goinglong term,” he said. “This [USSV]is getting us started, getting us acouple of prototypes that we can ex-periment with and then looking atsome of the harder problems forhow you operate and control thosevehicles.” — Jason Ma


COMPANY HAS DESIGNS ON FERRY OFTHE FUTURE


Reproduced by permission from theSeattle Post-Intelligencer, Tuesday,August 24, 2004, by the SeattlePost-Intelligencer Staff

Ferry rides of the future could befaster and smoother, if aBremerton company’s invention

takes off.

Advanced Marine Concepts has de-veloped what it says is a new designfor hydrofoils — boats with under-water wing-like structures that canlift the vessels above waves. Twoprototypes of its hydrofoil, calledDragonfly, will be built later thisyear.

Eric Anderson of Advanced MarineConcepts shows a Dragonfly model,a hydrofoil for the commercial ferryindustry and the military.

The Bremerton company — startedin 1998 by Philip Whitener, a formerBoeing Co. engineer, and Eric An-derson, chief executive of Art Ander-son Associates — eventually plans toshow its prototypes to the commer-cial ferry industry and the military.

As a hydrofoil’s speed increases, theunderwater wing-like structure liftsthe boat off the water. The results are asmaller wake, smoother ride and lessfuel consumption.

“I think they are the future,” said DickHayes, executive director of KitsapTransit.

The agency is trying to get funding tobuild a 149-passenger boat that wasdesigned by Art Anderson Associ-ates, Hayes said. The new vesselwould reduce fuel costs by about 25percent, he estimates.

Hydrofoils aren’t new and can befound on boats — even wakeboards— around the country. AlexanderGraham Bell toyed with one in theearly 1900s, according to Encyclope-dia Britannica. Boeing began produc-ing them in the 1960s for commercialand military uses; it ended the com-mercial business in the mid-1980s.

Whitener, who worked for Boeing for42 years before retiring in 1983, wasthe engineering manager of a Boeinghydrofoil developed for the Navy.

Advanced Marine Concepts’ proto-type is unique, Anderson said, be-cause it is designed for boats with awide beam. It can also create its ownair cushion, which helps the boat tran-sition to the wing-like structure, with-out using fans, which consumesmotor power, he said.

Radix Marine Inc. in Silverdale ismanufacturing the company’s proto-types, which will be 15 feet long by 8feet wide and seat a driver and up tosix passengers.

*********

CORSAIR FOILER 2200

By Michael Hauenstein

Reprinted with permission fromSoundings Publications LLC.

Trailerable trimaran builder Cor-sair Marine has begun produc-tion of its new Foiler 2200 center

console power catamaran.

The Foiler uses an aluminum hydro-foil designed by Morrelli & MelvinDesign & Engineering of Hunting-ton Beach, Calif., designers of SteveFossett’s record-setting 125-footsailing catamaran Cheyenne. Lo-cated between the hulls abouttwo-thirds of the way from the bowto the stem, the hydrofoil is shapedlike an inverted T and spans the tun-nel from the bottom of one hull to thebottom of the other. The hydrofoiland hulls work together for betterperformance, ride and handling, ac-cording to Corsair, and create a dryerride and less wake. The companysays the hydrofoil lifts the hull clearof chop and reduces drag.

“The ride is just miles better than anymonohull in a chop,” says CorsairMarine owner Paul Koch.

Corsair uses the same foam-coresandwich construction as in its sail-ing trimarans, which it has beenbuilding since 1985. The trailerableFoiler displaces 2,920 pounds with a

Photo By Phil H. Webber, P-I

The buzz around redesigned hy-

drofoil calls it smoother-riding,

more fuel-efficient


CORSAIR FOILER 2200(Continued From Previous Page )


pair of Honda 90-hp outboards. It canaccommodate optional power up to260 hp from single or twin outboards,according to Corsair.

The cat tops out at more than 50 mph,according to Koch. “It is very fast,smooth and stable, and leans intoturns,” he says, explaining that theFoiler’s asymmetrical hulls accountfor that turning characteristic, un-common for a catamaran. Base pricewith standard 90-hp engines is$62,510.

Contact is: Corsair Marine, ChulaVista, Calif. Phone: (619) 585-3005.www.corsairmarine.com

Contributed by Martin Grimm (IHSMember)

Ihave just been reading the pro-

gram for the RINA High SpeedCraft Conference (17-18 Novem-

ber 2004, RINA HQ, London). It wasnice to read that a paper on a hydrofoildesign is being offered, but with anunusual twist.

Here is the description of the paper:“Design of High Speed Low WakeHydrofoil Passenger Ferry” EndicottM. Fay, Teignbridge Propellers Ltd,UK

In many areas around the world it hasbeen imperative that fast passengerferries provide fast reliable serviceacross protected harbours, bays andrivers. While traveling at high speed,the existing ferry configurations cre-ate relatively low, high-energy wavesthat can erode shorelines and upset

HIGH SPEED CRAFT CONFERENCE

small vessels. The paper introduces atrimaran-configured hydrofoil to re-duce the wake to an acceptable levelwhile maintaining the speed neces-sary to provide a competitive service.The design will provide a passengercarrying capacity of 350 and cruisespeed of 35 knots. The hydrofoil willbe a canard style arrangement using adiesel electric drive system with apair of pod drives. The paper focuseson the preliminary design of the ves-sel with emphasis on the hull design,hydrofoil arrangement and propul-sion system.

From Speed at Sea, June 2004

By Doug Woodyard

The maximum installed waterjetpower per vessel has risen fromaround 2,000kW in the 1980s to

quadruple-jet installations with apower input of 70MW today.Waterjets designedto absorb over25MW are primedfor service and ap-plications callingfor unit powers of50MW and 250MW per vessel -are being ad-dressed by design-ers.

Providing an impe-tus for the develop-ment of a new largewaterjet genera-tion is Japan’sTechno- Super-liner (TSL) ferryproject at MitsuiEngineering &Shipbuilding. The 140m long,

POWER LEVELS MULTIPLIED IN NEWGENERATION THRUST

14,500gt aluminium -hulled vessel isdesigned to carry 725 passengers and210 tonnes of cargo on a1,000-nautical mile domestic route ata service speed of 37 knots, with amaximum speed of 40 knots. Ser-vices between Tokyo and theOgasawara Islands are due to startnext year.

Rolls-Royce was commissioned tosupply the twin Kamewa 235waterjets, each to be driven by a GEMarine LM2500+ gas turbine. Withan impeller diameter of around2.35m, each jet is designed to handleup to 27MW.

Twin Kamewa 235 WJ are specified for the TSL.

Each has an impeller diameter of about 2.35 m.

Few could have envisaged that

the waterjet would evolve in 20

years or so from an alternative

to the propeller for leisure craft

and shallow draught vessels into

a powerful propulsor for

hi-speed commercial and naval

tonnage.


POWER LEVELS MULTIPLIED IN NEWGENERATION THRUST(Continued From Previous Page )

Kamewa’s established stainless steelSII series waterjets have proven effi-cient and reliable propulsors,Rolls-Royce notes, but when consid-erably more input power has to be ab-sorbed, and impeller diametersexceed 2m, a new approach to designand construction was dictated.

The resulting VLWJ (very largewaterjet) design, addressing inputpower applications from 20MW to50MW, is divided into a series of ele-ments, with the inlet duct integratedinto the hull structure and the impel-ler chamber bolted to the duct and thetransom. Outboard ofthe impeller chamber isthe guide vane chamberand the steering/revers-ing unit; the latter is op-erated by a hydraulicsteering actuator lo-cated inside the vesseland stem that protrudesdownward from thecompartment over thewaterjet units.

The impeller shaft issupported by a wa-ter-lubricated bearing inthe guide vane cham-ber, with the seal box atits inboard end on theinlet duct, and sup-ported within the hull by a split bear-ing. The massive thrust is taken by aseparate thrust block in the hull, con-nected to the impeller shaft by a stubshaft and coupling.

Each driveline for the waterjets in-corporates two bearings from Britishspecialist Cooper Bearings. A440mm design serves the intermedi-

ate shaft while a heavier duty 440mmbearing is integral with the waterjet.Overlapping with the VLWJ, the wellestablished Kamewa S-series em-braces 11 models with input ratingsfrom around 1,500kW to 24MW.

The hydrodynamic performance ofthe mixed-flow pump is sustained bybuilt-in bearings which keep the im-peller in the correct position and pro-vide control of tip clearance. Theoutboard bearing location also sim-plifies the overall load distribution inthe aftship and promotes efficient useof the inlet duct as a load-carryingstructure. Stainless steel is used as themanufacturing material throughoutto maximise wear and corrosion re-sistance.

Five impeller blade angles, eightpump outlet nozzles and at least 10inlet duct design variations are avail-able to optimise a waterjet for thegiven application. Simple and mini-mal cable installation is fostered by acomputerised databus- based systemfor steering and reversing control,which can be used for both manualand joystick manoeuvring. Redun-

dancy and realtime control with ahigh level of security is claimed bythe designer.

Among the latest references forKamewa S-series waterjets is the73m-long catamaran ferry Fair-

weather, which entered service thisspring with the Alaska Marine High-way System on a 135- nautical-mileroute (Speed at Sea, April 2004).With capacity for 250 passengers and35 large cars, the Nigel Gee-de-signed/ Derecktor-built vessel has aservice speed of 35 knots at 85 percent maximum continuous rating ofthe 14.4 MW propulsion plant basedon four MTU 16V595 TE70 dieselengines.

Each engine, derated todeliver 3,600kW at 1,750rpm, drives a Kamewa90SIl steerable/revers-ible waterjet via aReintjes VLJ2230 gear-box and Centa compositeshafting.

Typically servingsmaller passenger fer-ries, rescue boats andsmall high speed navalcraft - with four modelscovering inputs up to3,000kW - KamewaA-series waterjets wereclaimed to be the first in

the world to usemixed-flow pump technol-

ogy. In conjunction with hydrody-namically- optimised design andexacting production techniques, thisfeature reportedly achieves a 5-10 percent higher efficiency than compet-ing axial-flow waterjets.

The original article goes on to de-scribe several other waterjet designs

The Rolls-Royce VLWJ design addresses input power appli-

cations from 20MW to 50MW. Note technician on top.





of the IHS website.


Disclaimer






TIP-DRIVEN IMPELLERS PROMISEBENEFITS


Scalloped Flippers Of Whales

Could Reshape Wings

By Steven AshleyReprinted by permission from Scien-tific American, August 2004

One day in the early 1980s FrankE. Fish noticed a small statue ofa humpback whale in a Boston

sculpture gallery. On closer exami-nation, he saw that the creature’slarge, wing-like pectoral flipperswere studded with evenly spacedbumps along their leading edges.Fish was taken by surprise. As a spe-cialist in the hydrodynamics of ver-tebrate swimming, he knew of nocetacean flippers, fish fins or avianwings that bore such odd features -

BUMPY FLYING

From Speed at Sea, June 2004

Specialists at the UK’s Universityof Southampton have carried outa concept investigation using a

tip-driven electromagnetic propulsoras part of a waterjet propulsion unit.Potential benefits are hydrodynamicperformance improvements, easierassembly and integration into the hull,and greater flexibility in machinerylocation.

Aprimary advantage is that there is noneed to insert a driveshaft within thewaterjet inflow; this significantly re-duces cyclic variations in thepropulsor inflow and removes an areaof flow separation around the shaft. Italso provides the designer withgreater freedom with regard to thetypes of propulsion systems availableand where they can be placed withinthe vessel.

Concept viability was examined byconsidering the performance of an ax-ial-flow electromagnetic thruster de-veloped for the Remote OperatingVehicle (ROV) market and numeri-cally studying its performance withina typical waterjet inflow. A study wasalso conducted to examine thescalability of such propulsion units.

It was concluded that for a typical sizeof waterjet with an input power re-quirement of 110kWand a diameter of0.25m, the maximum delivered powerat 2,200 rpm would be 90kW. The de-sign would offer the benefits of noshaft-induced losses and reduced cy-clic blade loadings, and should de-liver a higher thrust than comparableconventional waterjet units usinggeared electric motor drives.

all of those have smooth front edges.He mentioned this to his wife andconjectured aloud that the artist musthave made a mistake. Thestoreowner, overhearing Fish’s com-ments and knowing the sculptor’smeticulous attention to detail, soonproduced a photograph that clearlyshowed the humpback’s lumpy flip-pers. Fish marked down the unusualprotuberances for future research.

After intermittent study over the nexttwo decades-involving in one in-stance the sawing off of three-meterlong flippers from a rotting, beachedhumpback-the biology professor atPennsylvania’s West Chester Uni-versity and several colleagues haverecently shown that the whale’sknobby side appendages in someways trump the more conventionalsleek designs of both human and na-ture.

Working, with fluid dynamics engi-neer Laurens E. Howle of Duke Uni-versity and David S. Miklosovic andMark M. Murray of the U.S. NavalAcademy, Fish fabricated two56-centimeter-long plastic facsimi-les of humpback pectoral flip-pers-one with the characteristichumps. one without. In wind tunneltests at the Naval Academy, the scalemodel of the smooth flipper per-formed similarly to a standard air-plane wing. The hump back flipperreplica meanwhile exhibited signifi-cantly better aerodynamic effi-ciency.

Driving the waterjet impeller via itsblade tips completely eliminates thepresence of the driveshaft protrudingthrough the waterjet duct walls andupsetting the onset flow to the impel-ler. Furthermore, the length of thewaterjet inlet duct must be kept asshort as possible to avoid additionaladded weight from the entrained wa-ter; and the ramp angle of the ductmust be as shallow as possible toavoid excessive flow distortion.

In conventional waterjet systems withshaft-driven impellers these two di-mensions are constrained by the posi-tion of the engines. A rim-drivenimpeller, however, should allowgreater freedom with the positioningof the duct within the hull.


BUMPY FLYING(Continued From Previous Page )

As the researchers reported in theMay 2004 issue of Physics of Fluids,

the whale’s bumpy-fronted flippersgenerate 8 percent more lift and asmuch as 32 percent less drag thancomparably sized smooth flippers.Further, the humpback’s large, scal-loped fins withstand stall at angles ofattack (into the on-rushing flow) 40percent steeper than their seemingly

more streamlined counterparts.“These structures are so counter toour understanding of fluid dynamicsthat no one had previously analyzedthem,” Fish says.

The key reason for the improved per-formance are the pairs of coun-ter-rotating swirls created at eitherside of the leading-edge bumps,called tubercles. The tubercles act as

vortex generators," Howle explains.“The swirling vortices inject momen-tum into the fluid flow, which keepsthe f1ow attached to upper surfacerather than allowing it to separate asit would otherwise. This effect de-lays stall at higher angles of attack.”As a result, the leviathans can maketighter turns and maneuver morenimbly - a capability that comes inhandy when hunting fast-movingschools of herring and sardines.

Fish, who has patented the concept oflumpy lift surfaces, says that tests of amore accurate flipper model andfunctional optimization of the tuber-cle geometry are in the offing, whichcould lead to better man-made wings.Improved resistance to stall couldadd a new safety margin to flight andcould also make aircraft more agile.

“This discovery has potential

applications not only in airplane

wings but also in airplane propellers,

helicopter rotors and ship rudders,"

Howle notes. He speculates that the

next America’s Cup victor might

tack more sharply using a bumpy

rudder.

****************************

As a result of your editor making the“IHS Core” aware of this article, sev-eral interesting responses were re-ceived; one of which is reproducedhere. Others will be published in theSpring Newsletter.

From Tom Speer: “Personally, Iwasn’t convinced by the article. Forone thing, it’s not necessarily the casethat they evolved for hydrodynamicreasons. There are certainly enoughexamples of strange biological devel-opments, so long as they don’t do toomuch harm. I doubt a peacock’s tailis especially aerodynamic, for exam-

ple. What if whale mates just like thefeel of being rubbed by ribbed flip-pers better than smooth ones?

“There’s a fair amount of research inthe literature on various leading edgedevices like sawtooth shapes, etc.These haven’t proven to be especiallyhelpful except in very specific cir-cumstances - typically at lowReynolds Numbers where laminarseparation may be a problem.

“Much the same goes for vortex gen-erators. If you have separated flow tobegin with, vortex generators pay offby promoting attached flow. But ifthe flow is attached already, vortexgenerators just add drag. A test pilotfriend calls them “the horns of igno-rance” because they’re used to fix un-expected problems.

“At the same time, there are similarstructures that are designed for spe-cific purposes. One is the “Gasterbump”. It’s kind of like a single tu-bercle on the leading edge near theroot of a swept wing. The purpose isto stop attachment line transitionalong the leading edge by causingdisturbances from the fuselageboundary layer to be diverted fromflowing outboard along the attach-ment line. The bump allows the lead-ing edge to start with a freshboundary layer at the bump. Sincethe whale flippers often act highsweep angles, the tubercles may dothe same thing. See page 1 of NASATechnical Paper 3623 for additionalrelated information”

Bill Degentesh wrote: “Some timeago, in celebration of the Wright Brosfirst flight, a Public Television Spe-cial examined the rather sparse scien-tific and engineering data they had, in

Pectoral Flipper Replicas with

and without bumps, went

fin-to-fin in wind tunnel tests

Photo Courtesy of Prof. Howle



their day, to draw from when design-ing the Wright Flyer. One of thebetter references of that day was a setof design tables by the German GliderPioneer, Lilienthal. The WrightBrothers found Lilienthal’s dataoverstated the lift, and understatedthe drag of the airfoil wing, and sub-sequently had to conduct elaboratetests of their own to ascertain the cor-rect performance. The Wright resultswere said (on the program) to be ac-curate to within 3%, based on currentknowledge, while Lilienthal over-stated lift by 1/3 or more.

“How could Lilienthal, a good scien-tist with a fine record of success in hisglider experiments, have misstatedhis results? His Gliders certainlyflew well.

“Perhaps it was airframe workman-ship - perhaps the Lilienthal wing didNOT use a smooth leading edge, butrather the airfoil ribs bulged substan-tially, protruding the fabric, to pro-duce some of the dual-vortex liftenhancement recently noted? TheWright-built Flyer in the Smithsonianhas smooth leading edge air-foils...and illustrations of a Lilienthalglider which I recall from my youth,displayed wing-ribs with definiteprotrusions - enough to cast a shadowon the wing surface.

Could the error in Lilienthal’s data besimply the omission of a statement ofthe necessary size of the rib- protru-sions? Someone perhaps should con-tact the History Detectives!”

In response to Tom Speer’s mes-

sage, John Meyer wrote: “We canalways count on you for a good re-sponse, Tom. Thanks. I guess we

need to mull this over and need to pur-sue the aero tests in more detail.

“I have heard similar remarks re: Atest pilot friend calls them “the hornsof ignorance” because they’re used tofix unexpected problems. But thenagain they DID fix problems, so notreally a bad idea.”

Tom Speer responded: “Please don’tmisunderstand me - I think tuberclesare a valid and interesting area of re-search. But I wouldn’t expect thatsomeone could just sand a bunch ofbumps on a leading edge and get a sig-nificant, or even a measurable, gain inperformance for a hydrofoil. WhatI’d like to see is an investigation thatintegrated a computational fluid dy-namics element and an experimentalelement, where each guided and sup-ported the other. I think that’s the bestway to both understand the fluid dy-namics and to come up with some-thing that can be engineered.

Bill Degentesh wrote again: “Per-haps the ‘History Detectives’ are atwork already. The validity of the cur-rent ‘horns of ignorance’ patent de-pends upon originality - no prior artmay exist - and if any priorwing-design used protrusions for liftenhancement (any discovery countsas prior art), then prior art does exist.

“My own thought was that Lilienthalmight have been the first… TomSpeer indicates (in a IHS posting) thatLilienthal’s wing was fully describedin his own tables and reconcilablewith the Wright’s wing. That beingthe case (I do not plan to check)Lilienthal did certainly not use vor-tex-enhanced lift obtained throughprotrusions.

“I hope Tom is right - and also there isno prior art - added lift and reduceddrag would enhance both aircraft and

hydrofoils. The concept of Europevia the sea within 24 hours has al-ways interested me; the prospect thetechnology for this is patentable (andthe patent legally defensible) willcertainly excite investment interest.”

[Editors Note: Other comments willbe published in the Spring Newslet-ter since this topic has generatedconsiderable interest.]

Solar Electric Boat Design

(Abridged) – “I have a question thatyou might be able to help on. I ampart of a solar electric boat team fromThe College of New Jersey. We take aboat up to a buffalo river to race ev-ery year. This year we are designinga new hull. We run primarily twoevents: Sprint (a 300 m drag race) andEndurance (a 2 hour race in which themost laps is desired). Building a hullruns into a problem here. The endur-ance event is worth more points andusually speeds of around 5 mph arekept for the 2 hours. Since we run offof only two batteries in this event, ef-ficiency is vital. During the sprint,speeds of around 25 mph are thegoals. Last year our boat was adeep-V towards the bow and this dis-placement hull kept us from ever get-ting on plane in the sprint event. Thehull surprisingly did not perform thatwell in the endurance heats either, butI think this is due to our larger weight.I was wondering how you thought acatamaran might do in this type of ap-plication. I was wondering could itget on plane or would it at least dowell in the sprint portion. I am as-suming it would do very well atspeeds of the 5 mph but I was wonder-

BUMPY FLYING(Continued From Previous Page )

INTERESTING MESSAGE




SAILOR’S PAGE

By Dr. Ian Ward, Past PresidentIMCA, Developer of the First DinghyFoiler, Bifoiler and Unifoiler Moths

This is a continuation of Dr. Ward’sarticle that appeared in this section ofthe Autumn 2004 Newletter.

Misconceptions

There has recently been signifi-cant international publicity con-cerning foiling Moths, thanks to

Rohan Veal’s efforts. Hopefully thiswill result in new Moths entering thecompetition and more boats racingregularly.

While sailing magazines around theworld have interviewed top sailors ofvarious classes about their views onfoiling, surprisingly they have largelyoverlooked the small core of peoplecurrently developing these craft. Thecommentators should also take theopportunity to sail Dinghy Foilersthemselves and recognised the truedifferences!

Some articles have presented signifi-cant misconceptions about foiling,how it works, the pros and cons andthe role of the International Moth As-sociation in fostering this significantstep forward in sailboat design. Areasof misconception include:

A) Stability: Sailing on foils is easierthan it looks, being more stable thanexisting Moths without foils. There isconsiderable dynamic stability gen-erated by a foil around 800mm wideas opposed to a 300mm wide dis-placement hull.

B) Dinghy qualities: Some designersare still trying to add stability to din-ghies by using a wide foil base withsurface piercing wing mounted foils.This makes the boat excessively sta-ble removing the possibility for skil-ful sailing to achieve maximumefficiency and responsiveness. Thedinghy foiler concept forces the sailorto use his body weight and skill toachieve sailing equilibrium, ratherthan relying on the foil restoringforces, as generated on a trifoiler, tomaintain balance. This can lead to amore efficient (greater lift to drag ra-tio) mode of sailing. Miller’ssailboard foiler is an exceptional ex-ample of this efficiency. The analogymight be likened to the often quoted

case that glider pilots fly more effi-ciently than powered aircraft pilots.

C) Dinghy Foiler: By heeling the Din-ghy Foiler to windward, not only doesthe rig produce some lift, but also theweight of the skipper, rig, and hull arenow out of water and to windward ofthe centre of lift on the foil. All areworking together to provide a posi-

tive righting moment. This is onlypossible with foils arranged on thehull centreline.

D) Upwind: When sailing upwind,even with the hull still partiallyhullborne, the foils provide signifi-cant lift which can be more efficientthan pure displacement sailing. Thebest foiling Moths have consistentlyshown they can sail both higher intothe wind and faster upwind than dis-placement hull Moths. DinghyFoilers are therefore not just one-tackspeed machines.

E) Tacking and Gybing: There maybe a perceptions that foiling is OK forstraight line sailing, but the boatwould be slow when tacking and

jybing as is thecase with cata-marans. This isnot so! Foilermoths are able totack ‘on a dime’and simply keepgoing! Theyeven sail throughjybes, maintain-ing high speedand remainingeasy to handle.Well sailed, theyare faster to tackand safer to jybethan conven-

tional Moths!

F) Tactical racing: Tactics are a criti-cal part of dinghy sailing. As DinghyFoilers have been found to go higherand faster upwind and tack faster thanconventional boats, the ability to racetactically remains crucial! It wouldalso appear Dinghy Foilers are fast

DEVELOPMENT OF DINGHY FOILERS

Fastacraft Bifoiler


enough to tack downwind as well,again requiring tactical skills whenracing.

G) Height control: The most difficultaspect to foiling is controlling heightand countering longitudinal pitching.Current Bifoiler Moths utilize a sen-sor wand activated elevator on themain centreboard foil. In some condi-tions, this can induce significantheight variations with the hull occa-sionally touching the water. Levelflight just above the waves would nat-urally be preferable and is an area thatstill requires refinement. TheUnifoiler offers one potential solu-tion.

H) Displacement performance: Inlight wind while hullborne, foils cancertainly slow the boat. Experiencehas shown that moving bodyweightforward and reducing the foil angle ofattack can minimise overall resis-tance. By keeping the boat light andfoil size to a minimum, it is found thatwhen displacement sailing the foilsare not as great a disadvantage as ini-tially thought. Proposals to further re-duce resistance in light airs includetilting, retracting or folding the foilsor allowing them to align with theflow. These options remain to be ex-plored.

I) Sensor simplicity: In its current ba-sic form, the height control sensorconsists of a wand that adjusts the lift-ing foil attitude. Given the complex-ity of many high performance crafttoday, such a sensor should not beseen as “complex” as sometimes re-ported. I suspect it is simply that thefunction of the mechanism is notproperly understood. Some foil ar-

rangements can even operate with nomoving parts.

Ideas For Possible Further Devel-

opment Of Foilers

The current “bifoiler” arrangementworks very well under most condi-tions. I congratulate John and GarthIlett in persevering to develop thisvery good solution and make it avail-able to other sailors. For those want-ing to get into foiling right away, Irecommend buying a set of foils fromFastacraft.

An alternative is to make your ownfoils. This is not so difficult or expen-sive. Be very sure to make themstrong enough noting you are sup-porting the entire weight of boat andcrew. My home-made timber and car-bon foils cost around AU$300 to pro-duce. The Australian Moth website isbeing used as a forum for sharing de-tails on how to build foils as well aswhere to buy them and how to get thebest performance out of them.

I believe we should be looking to de-velop foil systems which are simpleto attach and can be easily retracted.They should be strong, light, cheapand simple to operate and provide asmooth transition from displacementsailing to foiling. They should also

DEVELOPMENT OF DINGHY FOILERS(Continued From Previous Page)

provide sufficient stability to over-come some of the difficulties of han-dling the current narrow skiff Mothsbut not so much as to override theskills inherent in dinghy sailing. Thecentreboard and rudder mounted foilsmeet most of these requirements.Many uncertainties remain in thefield of Dinghy Foiler design and fur-ther design advances can be ex-pected. This does not yet requireadvanced hydrodynamics not com-puter aided design. Engineering ex-perts do not have all the answers andneither the initial development ofsailboards or dinghy foilers have re-quired such skills. Proper engineer-ing design can surely help refinedesigns, but the basic configurationsneed to be conceived and prototypesbuilt by those prepared to test bythemselves. Initially no one thoughtbifoilers would work and I suspectthe same scepticism may exist forUnifoilers.

An excellent discussion forum forsuch developments is available atwww.boatdesign.net. This includestest results and freely provided ideas.You can also contribute ideas your-self. Technical discussion is now alsoavailable at the IMCA website forumwww.moth.asn.au/forum/index.php

Bifoiler Tipped Showing Foils and Struts







MEMBER BENEFIT






[email protected]

INTERESTING MESSAGE(Continued From Page 9)


2002-2005 2003-2006 2004-2007

Jerry Gore Mark R. Bebar Sumi Arima

James H. King William Hockberger Malin Dixon

Kenneth Spaulding George Jenkins John R. Meyer

John Monk Dennis Clark William White

ing how you thought it would do atthese lower speeds. During the sprintwe start from a dead stop and go 300meters so time to get up on plane isimportant. I have been investigatinga cat with a hydrofoil involved thatyou could change angle of attack so itcould help us get on plane in a spritrace and be changed to reduce thedrag in an endurance race. Your post-ing about hydrofoils was very help-ful, and I would like to know moreabout hydrofoils and if you think itwould be feasible and advantageousto use it on a project such as this. Ourwebsite is: Any opinions would begreatly appreciated. Thanks for yourtime. Brad Lynch: [email protected]

mote vehicles and equipment forRibicoff Underwater Products, RealEight Inc., Harbor Branch, TaylorDiving and Perry Submarine. He metSam Bradfield in 1987 at Florida In-stitute of Technology in Melbournewhere he was a sailing instructor forthe school. He has been working to-gether with Sam Bradfield ever since.They develop and sail hydrofoil sail-ing boats including NF3, Mosquito,HS21, EIFO, and Rave byWindrider. Currently, he and Sam aredeveloping a hydrofoil sailboatnamed SCAT, a 37 footer being de-veloped for offshore racing.

Leonard Hanson - Leonard gradu-ated from the University of Manitobain 1980 with a General Science de-gree and in 1984 with a degree inCivil Engineering. He moved to Sur-rey, British Columbia, Canada in1986 where he joined the SurreySailing Club, a dinghy sailing clubthat is racing intensive. Interest in hy-drofoils developed as a consequenceof attempting to wring more and morespeed out of the small sailboats. In-formation from the local library wasused in order to experiment withsmall hand made hydrofoils to attachto his own boat, a fourteen foot Tasarwith 130 square feet of sail area andweighing in at 155 pounds (sans cap-tain or crew). The objective is to de-velop a hydrofoil kit that can beadapted easily to existing sailboatsthat will provide extra speed at lowcost.

David Helgerson - David is a NavalArchitect and Marine Engineer whograduated from Webb Institute of Na-val Architecture in 1977, As Techni-cal Director for the Advanced MarineCenter of Computer Sciences Corpo-ration, he is responsible for auditingquality assurance activities withinCSC AMC and supports technicalprojects. Mr. Helgerson’s career hasincluded a wide range of projectsfrom early stage concept studies

through detailed design and construc-tion support. Primarily, his experi-ence has been with US Navy shipsand other US Government ships, witha strong emphasis on Strategic Sealiftand auxiliary ships. He was a USDelegate to the Electronic CommerceWorkshop held in conjunction withICCAS’97 in Yokohama, Japan, Oc-tober, 1997.

Matthew Jabloner – Matthew has aCivil Engineering degree from theUniversity of Delaware and is em-ployed by the US Navy in Washing-ton State. He has worked on a varietyof civil and environmental engineer-ing projects and programs specializ-ing in water quality regulatory issues.While his professional work does notinvolve hydrofoils he has had a inter-est in them since his grandfather tookhim to the Bell Museum, in NovaScotia, as a child.

WELCOME NEW MEMBERS(Continued From Page 2)

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