Flights of Discovery 50 Years at the NASA Dryden Flight Research Center

8/8/2019 Flights of Discovery 50 Years at the NASA Dryden Flight Research Center

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N A S ~RYDENFLIGHT RES


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FLIGHTSDISCOVERYby Lane E. Wallace

SO YEARS AT THENASA DRYDEN FLIGHT RESEARCH CENTER

The NASA History SeriesNASA SP-4309

National Aeronautics andSpace AdministrationNASA History OfficeWashington, D.C. 1996


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Library of Congress Cataloging-in-Publication Data

Wallace, Lane E., 1961-Flights of discovery : 50 years at the NASA D ryden Flight ResearchCenter / by Lane E. Wallace.p. cm .- The NASA history series) (NASA SP ; 4309)Includes bibliographical references and index .I . NASA Dryden Flight R esearch Center-History. I. Title.

11.Series. 111.Series: NASA SP ;4309.TL521.312.W354 1996629.1' 0720794' 88-dc20 96- 15797CIP

For sale by the U.S. Gov ernment Printing OfficeSuperintendent of D ocuments, Mail Stop: SSOP, Washington, DC 20402-9328


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To my friend JimFor believing


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Contents

Foreword viChapter Qne: A Place for Discovery 1The Role of Flight Research 4

Supporting National Priorities 9Dryden Contributions 13Conclusion 15Chapter Two: The Right Stuff 19The Place 2 1

A Unique Approach 28The People 30The Partnerships 35Conclusion 38Chapter Tbree: Higher, FasterBreaking the Sound Barrier

The X-PlanesThe X-15The Lifting BodiesJet-Powered Speed ResearchHigh Flight RevisitedConclusionChapter Four: Improving Efficiency, Maneuverability& SystemsEfficiencyThe Supercritical Wingmission Adaptive Wing

WingletsThe AD- 1 Oblique WingLaminar Flow Research

ManeuverabilityHiMATThe X-29The F/A- 18 HARVThe X-3 1


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This volume adds another dimension to "technical agility" of researchers at Dryden-a Early memb ers of theTeanz, although thethe existing literature about the history of the quality that has been an en omousl~mportant organiraiion that becHugh L. Dryden Flight Research Center ingredient in the process of discovery through Dryden Flight ReseaCenter was then calle(DFRC). While previous accounts-most flight here in the Mojave Desert. She has also NACA High Speednotably Dick Hallion's superb On the Frontier: captured the spirit of the role flight research Research Station. Lt$right, szanding: BeveFlight Research at Dryden, 1946-1981-cover plays in the aeronautics research and develop- Smith, ill^ Ann Bpart of Dryden's history from one perspective merit chain- unidentified, John CaJohn Rodgers, unidenor another, this is the first book to provide an Lane Wallace has included some "be- Huben ,yake,,Drakeoverview of the entire 50 years of the Center7 ~ hind-the-scenes" events that provide additional C. W lliam s; seated a-

insight into the human side of t h s highly kneeling: Mary Littlehistory from several perspectives. Claggert, Ed NollenzaIn this book, Lane Wallace also provides technical discipline. Dryden frequently puts the Dunn, Roxanah YancE. Beeler (early 1950insights into the process of research engineer- imovations and ideas of others to the ultimate ( N ~ ~hoto E96 43ing. She differentiates between flight testing test of real flight conditions. The products ofand flight research, and she describes the theory, wind-tunnel testing, and computational


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Aviation Safety 149Conclusion 151Chapter Six: Future Directions 155Current Projects 158Future Directions 161The Role of Flight Research 163A Unique Flight Research Resource 165Dryden Contributions 167Conclusion 169Chapter Notes 173Bibliographic Essay 179Glossary of Acronyms 180Appendix: Concepts and Innovations 181Photo Credits 188Acknowledgments 189Index 190About the Author 198


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"The history of any institution is really the historyof its people. The advances in aeronautics andspace technology at D ryden were literally boughtwith blood, sweat and tears."

e e e e e ~ e ~ e ~ e e e e ~ e ~ e e e o e e e e e e e e ~ e e ~ e e o e e o efluid dynamics-often develop ed elsewhere- thereof, the solving of practical problems.are absolutely critical ingredients in the process It's clear that Dryden owes its heritageof aeronautical discove ry. In this book, Lane to Walt, who died peacefully at his home inWallace has captured very effectively many of Tarzana, California, on 7 October 1995. Tothe ways in w hich Dryden has cooperated with him, for example, we owe our emph asis onits partners over the past half-century to ad- research instrumentation, on getting the data wevance the process of aeronautical discovery that need; on safety and quality assurance; onhas so often begun with Dryden's partners. careful flight planning by a small, integrated,

An impo rtant part of the Dryden spirit and highly competent team. We also got fromwas bequeathed by its first Director, Walter C. him o ur willingness to tackle the most difficultWilliams. He joined the National Advisory and seemingly impossible tasks. The projectComm ittee for Aeronautics (NACA ) in August structure we use today w as really invented inof 1940 . D uring W orld Wa r 11, he was a project these early years.engine er in the evalu ation of several fighter History records all of the technicalaircraft-the P-47, P-51, and F6F-looking at accomplishments in terms of M ach number,handling qualities, low- and high-speed flight altitude, maneuve rability, orbits, and the like.characteristics. As a member of Hartley A. For these alone, Walt will be remembered andSoulC's stab ility and contro l branch at La ngley honored. But historians will never capture inMem orial Aeronautical Laboratory, he was one words the zeal and zest that Walt put into hisof the NAC A's foremost research airplane life and work. This sam e spirit lives on today atadvocates. He led the first NAC A team at NAS A Dryden . The history of any institution isMuroc and becam e the first Director of what really the history of its people. The adv ances inwas to become DFRC aeronautics and space technology at Dryden

He had tremendous experience in the were literally bought with blood, sweat andflight testing of high-perfo rmanc e aircraft. As tears. I therefore dedicate this book to theDick Hallion noted in On the Frontier, Walt Dryden Team that has given so much to accom-"was an inq uisitive, take-cha rge sort of engi- plish the flight research mission for 50 years,neer, a man who believed that useful researchhad to confront actual problems and not be 17 April 1996 Kenneth J. Szalailimited to studying theoretical aspects of aero- Directornautical science." This outlook continues to be Dryden Flight Research Centerthe basis of our work here at Dryden-the studyof aeronautical phenomena and the applications

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Joshua trees in desert atsunrise

ess than 100miles north of the bustling international city of LosAngeles lies a barren, windswept landscape known as the Mojave Desert. It is anunfriendly environm ent known for blazing summ er temperatures and bone-chillingwinter winds, a place once described by then-C olonel Henry H. "Hap" Arnold as"not good for anything but rattlesnakes and hom ed toads."'

Yet for all of its desolation, the desert also contains unique g ifts. It offersunend ing days of piercing blue skies; dawns and sunsets that dust its rocky mountainsides with breathtaking hues of color. And while its arid landscape and dry lakebedssupport little vegetation, for the past half century they have provided an ideal envi-ronm ent for pilots, researchers and engineers to test and explore new concepts inflight.

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It was above this stark expanse of landthat the notorious "sound barrier" was finallybroken; that innumerable speed and altituderecords were set and quickly surpassed; that thefirst Space Shuttle proved it could land safelywithout power. It was here that the X-15 taughtresearchers valuable lessons about hypersonicsand space; that the first fully digital fly-by-wireaircraft was flown; and that a pilot successfullylanded a transport aircraft using only t h s t orengine control.

Over half a century, this desolate loca-tion has allowed innumerable technologies to beexplored, improved upon, and given enoughcredibility for industry to accept and applythem. And what began as a small, temporarydetachment to support a single research project

has evolved into a substantial National Aero- X- 1 with crew: left to right,nautics and Space Administration (NASA) Eddie Edwards; Bud Rogers,

Dick Payne, crew chiefifacility known today as the Hugh L. Dryden Henry GaskinsFlight Research Center. (NASA photoE-49-00039)There are three things that made theMojave Desert so well suited for flight research.The first was the area's flying conditions, whichincluded clear skies and 50 or 100 miles ofvisibility almost every day of the year. Thesecond was Rogers Dry Lake-a 44-square-mile natural landing site that General AlbertBoyd referred to as "God's gift to the AirForce."2 The third factor was that the lakebedwas surrounded by miles and miles of virtuallyuninhabited desert, providing a buffer zonewhere rocket and jet aircraft could be operatedsafely and with far fewer restrictions than a

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more populated area would require. research efforts the NACA had undertaken toThe Army's initial interest in the area expand the country's knowledge and under-

around Rogers Dry Lake was as a bombing and standing of aeronautics. Established in 1915,gunnery range in the years preceding World the NACA's mission was to "supervise andWar 11, and a formal army air base was estab- direct the scientific study of the problems oflished near the town of Muroc in July 1942.3 flight, with a view to their practical solestion."5But it was the The committee

Although the NACA and the advent of jetAir Force would continueuntil June of 1948 "neither engines and higher[to] confirm nor deny " speed aircraft thatthe story of Capt. Charles"ch uc kM eager's breaking highlighted the realthe sound barrier on 14 strengths of theOctober 1947, the LosAnpeles Times was one of a desert location. Thenumber of publications that new experimentalreported the story in lateDecember. Apart from the jet aircraft, startingfacts that Yeager had with the Bell XP-exceeded the speed of soundin the XS -I, the reporting 59A, requiredwas rife with so-called longer runways'jcacts" that were nothingmore than sheer speculation. than most air bases

Nearly two Years would had, and the classi-elapse, or example, beforethe XS-1 came close to the fied nature of the70,000feet the research required areported as already reached.The Times also reported that remote site forNACA research pilots flight testing. ~h~Howard Lilly and HerbertHoover had already "dupli- Muroc Army

cated Yeager's feat. " In Airfield, officialsfact, Hoover became theNACA 'sfi rst supersonic realized, was thepilot nearly three months perfect choice fo rafler the article appeared, inearlv March 1948. followed this kind of work.by Lilly about three weeks

later.(Air Force Photo)These same reasons led the Army Air

Forces, Bell Aircraft, and the National AdvisoryCommittee for Aeronautics (NACA) to chooseMuroc as the test site when they undertook thechallenge of designing and building a researchaircraft to break the notorious "sound barrier."In the fall of 1946, the first NACA contingentof 13 engineers, instrument technicians, andsupport staff arrived at the Muroc Army Air-

was to help thefledgling aero-nautics industryby conductingresearch thatmanufacturerscould not, eitherbecause the workwas too expen-sive, long-range,or requiredfacilities industrylacked.

By 1946,theNACA adalready madenumerous contri-butions to aero-nautics. But thecoming of thehigh-speed jetage at the closeof WorldW x IIbrought new

challenges. Ground facilities did not exist thatcould adequately simulate the dynamics of thetransonic environment, which included speedsabove Mach 0.85 but below Mach 1.2.The firstslotted-throat transonic wind tunnel, whichprovided much better data at speeds approach-ing and surpassing the speed of sound, was notdeveloped until 1950.6 A large part of therationale for building the X-1 was because at

field to support the X-1 effort.4 that time there was no other way to gatherThe X-1 project was just one of many reliable information about transonic flight.

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The Role of Flight ResearchIt was not only the lack of ground

facilities that provided thejustification forexploringideas in flight, however. Theimpor-tance of trying out new concepts and designs inflyable aircraft was understood even by WilburWright, who in 1901argued that "if you arelooking for perfect safety you will do well to siton a fence and watch the birds, but if you reallywish to learn you must mount a machine andbecome acquainted with its tricks by actualtria1.997

TheNACA shared Wright's belief, andflight research has always played a critical rolein the work of both the NACA and its successoragency,NASA. By the rnid-1960s, groundfacilities were much more capable than they hadbeen in the days of Wilbur Wright or the X-1,but NASA administratorJamesE.Webb stillconsidered flight research a critical activity. In1967he testified before Congress that

Flight testing of newconcepts, designs, and systems isfundamentalto aeronautics.Laboratory data alone, andtheories based on these data,cannot give all the importantanswers. . . .Each time a newaircraft flies, a "moment oftruth"' arrives for the designer ashe discovers whether a group ofindividually satisfactoryele-ments add together to make asatisfactory whole or whethertheir unexpected interactionsresult in a major deficiency.Flight research plays the essen-

tial role in assuringthat all the elements ofan aircraft can beintegrated into asatisfactorysystem.8That argument still

holds true today. No matterhow sophisticatedlaboratorytechnology becomes, comput-ers can only simulatewhat isknown. The unknown isalways, in a sense, unpredict-able. A computer can extrapo-late what should happen as alogical extension of what hashappened up to that point, butthe outcome cannot be as-sured until it is tested inrealistic conditions. Flightresearch is where that testingoccurs. It is that unique pointwhere the rubber meets theroad, where the aircraft,human, andreal-life flightconditionscome together forthe first time. And becauseflight research explores thatragged edge between theknown and the unknown, it isa place where discoveryhappens.

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no t have at least on e such moment.9 Some-times, the discovery shows only that th e compu-tational codes used to predict the performanceof the aircraft need to be adjusted. Other timesit turns the research in an entirely differentdirection, opening up a whole new set of ques-tions from those envisioned at the start of theproject.

In either case, it is these discoveries that

slowly expand ou r understanding of the worldof aeronautics. And it is the pursuit of thesediscoveries that differentiates flight researchfrom the closely related discipline of flight test.

The Air Force Flight Test Center(AFFTC) is situated just a short hike down theflightline from the Dryden Flight ResearchCenter at what is now Edwards Air Force Base.The flightlines of both centers display animpressive array of high performance aircraftand, to a casual observer, there might seem littledifference in the work the tw o facilities do .Both centers employ highly skilled pilots whofly new and experimental aircraft configurationsto precise test points. In both cases, data fromthose maneuvers is collected by various types ofinstrumentation and recorded or sent back to theground, where it is processed by engineers,technicians and analysts.

The difference between flight test andflight research lies no t in the mechanics of eachoperation, bu t in the questions that drive thework and ho w unexpected discoveries areviewed. In flight test, the objective is to com-pare th e airplane's performance against setspecifications it is supposed to meet. The idea isno t to explore new realms of aeronauticalknowledge, bu t simply to make sure that a newaircraft design or configuration performs in anacceptable manner. Unless the anomaly isbetter-than-predicted performance, unexpectedresults in a flight test program indicate prob-lems that need to be fixed. Th e informationgained through flight test is also directed towarda specific customer with regard to a specificproduct.

Flight research, on the other hand,gathers information that can be used by a muchwider audience fo r a wide variety of applica-tions. In addition, flight research involves

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much b m e r qwedm. 'Theabjmrtiwisnota p 1 ~o dm&@ 8 E h p h E ~&CZW hcertainway, bnt $0u~be - l d why tt &6d &.ndto expbre vaci~bzls & 2 ~ ~ &at perhr-m a e .~ s c o v ~ e s otprob- bb hebbut doors op&g h t ~ew r&&mat'p~dbil-iq.They giw mswcher~ g hpw into theworld beyond what web ,aise;n w pw-tiom and oftan l ~ dtodnPMy rrew Li-n~f~;eseslru=h.Bseovc~ryammd&a happen dl

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NB-52A (tail number 003)making a pass over one ofthe X-15s following alakebed landing. One ofonly three B-5 2As produced,003 was one of a pair ofhighly modifiedStratofortresses-the otherbeing NB-5 2B number 008-that were used to launch X-15s at speeds of 600 milesper hour and at altitudes ofup to 45,000 feet. Scenessuch as this typically tookplace 20 minutes or moreaf er the X-15 had toucheddown, because the NB-52returne dfiom a launch point200 to 300 m iles northeast ofEdwards. (NASA PhotoEC610034)

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Group airplane photo,X-24B, F -15 RemotelyPiloted Vehicle, F-I11Transonic AircraftTechnology, F -8 DigitalFly-By-Wire, F-104s,T-38, PA-30, Jetstar,Aerocommander, R-4 D(Gooney Bird), F-I I IIntegrated PropulsionControl System, and thesmall remotely-pilotedresearch vehiclesin the foreground(6May 1974).(NASA Photo ECN 40 29)

regions."lOThe problems have also become more

complex. In 1946,researchers were simplytrying to see if it was possib le for an aircraft tosurpass the speed of sound . Today, the goals arebroader. We want not just supersonic aircraft,but efficient, environment-sensitive supersonicaircraft, or highly m aneuverable supersonicaircraft. So d espite all the advances in aeronau-tics, flight research is still operating at thecutting edge of knowledge.

Even elements that are understoodindividually may interact in an unexpectedmanner when they are brought together in a

realistic flight environment. This is especiallytrue for any aircraft that requires a human pilot.Time after time, for example, computerizedflight contro l systems for aircraft have beentested successfully in simulators, only to exhibitdifferent tendencies in actual flight. One reasonfor this is that simulators rely on predicted datato model a new aircraft or system 's perfor-mance. But another cause is the simple fact thatpilots react differently in sim ulators, whereeven the worst mistake will cause them onlyembarrassment, than in an aircraft where thestakes are very real and very high. Yet if theend goal of aeronautical research is to improve

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1 products.A Furthermore,

the design of practical, flyable aircraft, it isessential to explore those reactions and discoverpotential problems with configurations ortechnology.

Indeed, another important function offlight research is that it forces researchers tofocus on those particular problems that are trulycritical to developing usable technology. Manyinteresting questions can arise in the course oflaboratory and ground research. Bu t putting apiece of technology on a flyable aircraft quicklydifferentiates those questions that are low-priority curiosities from those that suggestcritical issues to address. Furthermore, a prob-lem identified as critical cannot simply be pu taside to be studied later. It has to be solved.

In part because so many operationalproblems have to be addressed and solvedbefore a concept can be tried on an aircraft,flight research can also play an important rolein winning industry's acceptance for newtechnology. Technology that has been exploredin flight is generally more mature than conceptsinvestigated only in laboratory or simulatorsettings, leaving a smaller gap for industry tobridge in order to incorporate it into commercial

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there is a measure ofcredibility that can beachieved, almostinstantaneously, froma successful demon-stration of a technol-ogy on an actualaircraft in realistic7 light conditions. Asa former vice presi-dent of engineering atthe Boeing Commer-

cial Airplane Company argued, "laboratorydevelopment has great appeal and usually getssubstantial government support. However. ..the attainment of credibility is [also] an impor-tant national issue. It is dwing this second phasethat a technical concept achieves a state ofreadiness, validation and credibility such thatprivate industry and financing can assume theattendant risks."ll

In some cases, laboratory research issufficient for industry to see the benefits of aconcept and invest in it. Bu t especially astechnology becomes more complex and expen-sive, making a commitment to a new technol-ogy is an increasingly difficult and risky gamblefor industry to make. An idea that has beenproven successful in realistic flight conditions ismuch more convincing, because while it mightstill be uneconomical or impractical, industrydecision-makers at least know it can work.

Giving aerospace manufacturers theconfidence to invest in new technology can, inturn, increase their global competitiveness. Thishas important implications,because aerospaceis one of the few remaining fields in which theUnited States still has a trade surplus. If the

Flights of Discovery

Above left: SR-71crew members with aircr af.(NASA PhotoEC91056.Fr 16)


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SR-71BMach 3 trainer country is to improve its balance of trade andat sunset. overall economy, the aerospace industry must(NASAPhoto remain competitive.EC95 43351-1)

SupportingNationalPriorities

research conducted at Dryden12 over the pasthalf century has played an important role infurthering the country's priorities, whateverthey were.

In the post-World War I1era and theCold War of the 1950s, the drive was to de -velop aircraft that could go higher an d faster,

Of course, global competitivenesshas exploiting speed and power to maintain superi-not always been the driving national concern ority over Soviet aircraft and defense systems.that it has become in recent years. Bu t the flight Dryden's work reflected this theme with its X-

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planes and its efforts to improve a variety of systems of aircraft. Dryden's focus shifted with Robert McCall's famomilitary jet aircraft designs. After the launch of the nation's, leading to projects such as the mural entitledThe S~ i r i t f FlightSputnik in 1957, the space race also became a Supercritical Wing and winglets, which made Research depicts theaircra>flown duringhigh national priority, culminating in the Apollo aircraft more aerodynamically efficient, and to Dryden Flight Researeffort throughout the 1960s. At Dryden, those the world's first purely digital fly-by-wire Center'sfirst30 yearpriorities were paralleled by its X-15 and McCall completed theairplane, which opened a whole new realm of painting thelifting bodies research, as well as efforts such as efficient and capable aircraft design. renaming of the Centthe Paresev and the Lunar Landing Research The country's need for higher perfor- honor of Hugh LatimDryden.Vehicles. mance aircraft continued into the 1980s, leading (NASA Photo EC96

Another national priority in the 1960s to research at Dryden that focused on under- 43416-3 )was the development of a civil Supersonic standing the dynamics associated with moreTransport (SST). This goal spawned a number maneuverable and capable configurations. Theof high-speed research projects at Dryden, X-29, the HiMAT, the FIA-18 High Alphaincluding work with the Mach 3 XB-70 and Research Vehicle (HARV) and the X-3 1 re-YF-12 aircraft. But environmental concerns, an search planes al l reflected this priority in oneeconomic recession and a burgeoning fuel crisis way or another.in the 1970s shifted the country's priorities to Interestingly enough, the 1990s haveimproving the fuel efficiency and internal brought a renewed national interest in higher

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Key to AircraftA. YF-12: Predecessor o the SR-71, on a modified F-8from 1971 73.flew at Dryden in a high speed Concept now used on many transportresearchprogramfrom 1969-79. and fighter aircraft.

0. XF-92: First delta-wing aircraftflew at Dryden from 1951 1953.P. D-558-1: D-588-1 Skystreak wasflown from 1947-53 n a program toinvestigate safety of flight at transonicspeeds.

B. 74710rbiter Enterprise:747 shuttle carrier aircraft carriedEnterprise, prototype orbiter, aloftduring 1977 approach and landingtests at Dryden.

I. X-1: The X-1 became the firstaircraft to fly faster than sound onOctober 14, 1947. Pilot was then-Captain Charles E. Yeager, one ofthe several project pilots assigned tothe joint NACNArmy Air Corpsproject. Historyof Dryden dates to1946 and the X-1 project.

Q. M2-F2: First heavyweight liftingbody was the M2-F2, flown from1966-67. Damaged in a landingaccident and rebuilt as M2-F3 with athird vertical tail and flown from 1970-72. Now displayed at theSmithsonian National Air and SpaceMuseum.

C. XB-70: flown from 1967-69 n ahigh speed research program.D. X-15: Rocket-poweredresearchaircraft flew 199 missions from 1959to 1968. The X-15 still holds theworld's absolute speed (4520 mph)and altitude (345,200 ft) recordsforwinged aircraft.

J. HL-10: Fastestand highest flyingof the five lifting body designs flownat Drydenform 1966-75. Researchaided space shuttle program. HL-10now displayed at Drydenentrance. R. X-3: Dubbed the Flying Stiletto,X-3 flew from 1952-55 o gather dataon supersonic flight and use oftitanium and stainless steel in aircraftconstruction.K. X-4: Semi-taillessvehicle flownfrom 1948-54 n studies of stabilityand control at transonic speeds.E. B-52: Picturedcarrying the X-15,NASA's B-52 air launch aircraft,NASA 008 has been used since thelate 1950sto air launch a variety ofpilotedand unpilotedvehicles. L. X-5: First aircraft capable ofsweepingwings in flight, flew from1950-54.

S. PARESEV: Between 1962-64 thePARESEV 1A vehicle (paragliderresearch vehicle) studied wingconfigurations as possible methods ofreturning vehicles through theatmosphere from space.F. 8-50: A modified B-50, and anearlier B-29, were used to air dropresearch and experimentalaircraft inthe 1940sand 1950s.

M. HH-53: HH-53 aerial recoveryhelicopter carries NASA'sF-15318 scale remotely-pilotedresearchvehicle used in stall-spinresearch program. T.X-24B: Last of the lifting bodies,the X-24B flew from 1973-75 n aprogram aiding in development of thespace shuttle. It was developed fromthe X-24A airframe.

G. D-558-2: The D-588-2Skyrocket,dropped from the B-50 launchaircraft, flew from 1948-56to investi-gate the swept-wingconfiguration atsupersonic speeds. First aircraft tofly twice the speed of sound.

N. LLRV: Lunar Landing ResearchVehicle, flown in mid -1960s, devel-oped control system used on theApollo lunar module to land astro-nauts on the moon'ssurface and onthe Apollo astronauts' trainingvehicle.H. F-8SCW: Supercritical wingresearch was carried out at Dryden

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Shuttle mate/demate awith Space ShuttleEndeavour in it. Endehad just completed itsflight (STS-49) rom 71992 to I6 May 1992,this photo was taken.(NASA PhotoEC92 05169-1)


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and/or faster aircraft-but with a twist. Theimpe tus for high flying aircraft is fueled largelyby the need to ga ther inform ation on the Earth'satmosp here, and that avenue of research isfocusing primarily on sm all, remotely pilotedvehicles. NAS A's initiative for a High SpeedCivil Transport (HSCT) differs significantlyfrom the 1960s goal of a Supersonic Transportin that it now must be economical and environ-mentally sensitive as well as fast. Not surpris-ingly, therefore, the work Dryden is conductingto support NAS A's High Speed Researchprogram is loolun g not just at speed, but attechnologies such as achieving supersoniclaminar flow and m apping the parameters ofsonic booms. A national concern with makingaccess to space more economical is also drivingDryden's current research into reusable launchvehicles such as the X-33.

Not all of the research conduc ted atDryden fits neatly into these chronologicalnational themes. Efficiency, for ex ample, is animpo rtant issue in any aircraft design and hasalways been a concern for aerodynamicistsworking on furthering the basic research andtechnology knowledge base. Layered on top ofthose basic research efforts, however, are morefocused research programs such as the X- 15,the A ircraft Energy Efficiency (ACEE) pro-gram, or the Spac e Shuttle, which are mo reclosely tied to shifts in national concerns. Andon this level, there have always been inescap-able parallels between the focus of Dryden'sresearch and the nation's techno logical andecono mic priorities. This is hardly surprising, ofcourse, given that NACAINASA has alwaysbeen fund ed by the national government.Congress is unlikely to app rove funding forresearch that is totally irrelevant to nationalconce rns. Yet it is not just fun ding that drives

the type of research Dryden performs.The man agers and researchers at the

Dryden Flight R esearch Center understand thattheir mission is not only to adv ance their ownideas but also to provide support to other NASAcenters, government agencies, the m ilitary,industry and, in the end, the American public.Consequently, only perhaps 5 0 percent of thework the Center does is "exploratory" resea rchstemming from long-term objectives developedwith its various research partners. The otherhalf of its work comes from requests by othercenters, government agencies, the m ilitary, orindustry for help on other programs o r efforts.Program s on stall-spin charac teristics of sma llairplanes, tests of an exp erimen tal anti-mistingfuel, and research on sh uttle therma l tiles andtires are just a few of the many such projectsDryd en has undertaken over the years.Dryden Contributions

Yet w hether the research was initiatedby Dry den, industry, or by ano ther center oragency, the work conducted by the Center andits research partners over the past 50 years hasmade some very important contributions to theaerospace efforts of both gov ernment andindustry. In some cases, the impact of theresearch has been clear an d direct. The flightexperien ce with the X-15 and the lifting bodies,for exam ple, provided the space program w ithcritical information about the use of reactioncontrols and gave the designe rs of the SpaceShuttle the confidence to have it land w ithoutpower. Research with the X-3 led to the identi-fication of both the cause and a cure for a lethalinertial roll couplin g problem that had plaguedthe F-100 jet figh ter and other aircraft of the1950s. The Supercritical Wing has been applied

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to numerous aircraft, including all new largecommercial transports and the AV-8B Harrier,and winglets tested at Dryden have been usedon many corporate jets as well as on the Boeing747-400 and McDonnell Douglas MD-11airliners.

After a potentially dangerous pilot-induced oscillation (PIO) was discovered in thefinal pre-launch landing test of the first SpaceShuttle, Dryden engineers were able to design asuppression filter that fixed the problem withoutforcing a redesign of the Shuttle's entire flightcontrol system. Research into a Digital Elec-tronic Engine Control (DEEC) system with aPratt & Whitney FlOO turbofan engine resultedin a DEEC system being incorporated into thecompany's production model engines. A prob-lem with compressor stalls in an upper comer ofthe FlOO's operating envelope was also suc-cessfully analyzed and solved as a result of theresearch.

In other cases, the Center's research hasadvanced technology or understanding in areasthat have yet to be applied. The X-29, forexample, demonstrated the feasibility of acomposite, forward-swept-wing design. Thereis currently no production aircraft that incorpo-rates this particular technology, but that doesnot mean that there won't be one some time inthe future. The variable-camber, supercritical,variable-sweep wing Dryden investigated on anF- 111proved the validity of the technology,although it has yet to be used. Dryden research-ers, in partnership with industry, also developedan integrated, computerized flight and enginecontrol system that allowed a NASA pilot tosuccessfully land both an F-15 fighter jet and anMD-11 transport airliner using only throttlecontrols. This technology is too recent a devel-opment to have spurred any commercial appli-

Page 14

cations yet, but several tragic airline accidentshave been caused by partial or complete loss ofhydraulic power that rendered the flight con-trols useless. Since a propulsion control systemcould help prevent this kind of accident, itmight be incorporated into airliners before toolong. 3

Harder to trace, but no less important,are the less direct contributions made by re-search conducted at Dryden. There are manyinstances where, although the technology wasnot applied directly, the Center's researchexpanded the knowledge base of aeronauticalengineers or changed people's thinking on whatwas possible. In addition to the direct technol-ogy that was developed and transferred toindustry through the Digital Fly-By-Wireprogram, for example, the research created animportant element of confidence in the basicconcept. The fact that Dryden research pilotshad flown the fly-by-wire research aircraftwithout any mechanical back-up controls was afactor in determining how decision-makers'viewed the technology's reliability. That, inturn, led to the design of pure digital fly-by-wire systems for the F- 16 C/D and the FIA- 18Hornet fighters, and eventually the Boeing 777airliner.14

By the same token, Dryden's structuralflutter research with a Remotely Piloted Vehicle(RPV) led to improved real-time flutter analysisalgorithms for designers to use. The FIA- 18HARV is exploring actual airflow dynamics atextremely high angles of attack in order tomake the formulas used to predict this flowmore accurate. This information, in tum, canallow engineers to design aircraft that willperform better in that flight regime. And aseries of mathematical procedures developed byDryden researchers to extract previously unob-



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Joshbin free with cow andunidenrqied person(NASA PhotoB96 43403-5)

tainable aerodynamic values from actual aircraftresponses in flight, a process known as pararn-eter identification, has become an internationalstandard. This definitive contribution allowedflight researchers for the first time to comparecertain flight results with predictions.

In short, the contributionsDryden hasmade over its 50-year history have been asvaried as the aircraft its pilots have flown.Sometimes the

versus reach."l5 To take too small a step is todiscover nothing new. To take one too large isto invite catastrophe. And the burden of con-stantly walking the thin line between those twoextremes is one that every researcher at Drydencarries.

Walt Williams, head of the small NACAcontingent that arrived at Muroc to support theX-l program, recalled that the engineers "devel-

oped a very lonely

For no matter how well engineers andThe road to discovery is not an easy one. analysts try to anticipate every possible problemIn order to make contributions to technology or and reaction, physical exploration of the un-

to our understanding of aeronautics and aero- known is never without risk. There is always aspace, research has to be working on the cutting moment when someone has to make the deci-edge of knowledge. There is a constant tension sion that "enough has been done and it is timein flight research that is characterized as "risk to go fly, knowing that if a mistake has been

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made, someone can die . Yet it is the willingnessof people to step into that lonely abyss of theunknown-whether it was Lew is and Clarkexploring the western wilderness, Wilbur andOrville Wright launching the first poweredaircraft, Charles Lindbergh setting off acrossthe Atlantic, or Captain Ch arles "Chuck"Yeager pushing the X-1 through the speed ofsound-that has allowed progress to occur.

"We do these things," President John F.Kennedy said in his famous 1961 space chal-lenge, "not because they are easy, but becausethey are hard."l7 For 50years, the DrydenFlight Research Center has been a place where"h a rd problems have been welcomed. It is aplace where people are encouraged to questionand look for the unexpected, wh ere it is under-stood that the answers exist and the challeng e isto find them.

Hugh L. Dryden, the former NACAdirector of research for whom the NASA flightresearch center is named, on ce said that flightresearch separates "the real from the imag-ined."'* His statement is true in more ways thanone. In many cases, flight is that critical ele-ment in the interdependent disciplines of labo-ratory, wind tunnel and simulator research thatfinally turns an idea into hard, tangible reality.In every ca se, however, it forces researchers togo beyond im agined difficulties and grapplewith those very real, critical problems that willmake or break a technology or design.19

It is an effo rt not without risks or cost.Out of the original "X-series" and Douglas D-558 research airplanes, for example, four

Page 1G

exploded wh ile still attached to the launchaircraft, one c rashed in a stall-spin accident, onecame apart in rnid-air, and one crashed after acatastroph ic engine failure on take-off. Over theyears, no fewer than nine aircraft have been lostand a number of pilots and crew mem bers havegiven up their lives in the course of flightresearch projects associated with Dryden.20 Butthe research conducted at the Cen ter has alsoresulted in innumerable advances that havesaved lives, led to the design of better and m orecapab le aircraft, and expanded our understand-ing of the world and the atmosphere that sur-rounds it.

The Mojave Desert may be windy anddesolate but, in retrospect, it is far from barren.Fo r 50 years, its open spaces have contributedand been witness to the birth of discoveries thathave repeatedly revolutionized the art andscience of aeronautical design.

Cradled in the midst of that desertworld, the D ryden Flight Research Center hasgrown from a sm all, temporary detachm ent tothe premier flight research center in the country.And w hile Dryden has undergone a number ofchanges over the past half century, one thinghas never varied. No matter what its size orresearch focus, the Center has always been aunique place where people work a t the cuttingedge of kno wledge, whe re theoretical principleand real life come together, where discoveryhappens and where the imag ined becomes real.



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Aerial view of Muroc ArmyAirjield, 10 October 1946,just ten days after WaltWilliams and his small teamhad arrived and one daybefore the XS-I (laterredesignated the X-1) testprogram got underway withBell test pilot C halm ers"Slick" Goodlin's first glideflight in the experimentalrocket plane. The village ofMuroc app ears near the top-left corner of this photo w iththe tracks of the Atchison,Topeka & Santa Fe Railroadextending eastward acrossRogers Dry Lake. (Theywould continue to bisect thelakebed until they wereremoved in late 1953.) TheXS-I fueling area andloading pit were located at

the corner of the far west(left)end of theflightline, and a giantNorthrop XB-35 Flying W ingprototype bom ber may beseen taxiing across rom theWest Main Hangar.Williams' NACA team sharedspace, next door, in the EastMain Hangar. Two smallerhangars are visible in arecessed area to the right ofthe main hangars. The oneon the far right would betransferred to Williams'

Muroc F light Test Unit inApril of 1948 and it wouldserve as "hom e" for N ACAflight research operations orthe next six years.(Air Force P hoto)


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little more than a tent encampment. Barracks, acontrol tower, a concrete runway and a sewagesystem had been added in 1943,but the condi-tions were still appallingly rough.

For work space, the NACA personnelwere given part of one of two main hangars atSouth Base, and two small rooms fo r offices.The hangars w ere unheated and the desert sandand dirt blew through them constantly, creatingan ongoing problem fo r technicians workingwith delicate instrumentation. Engineers w ouldfrequen tly have to sweep a layer of dirt off theirdesks in the morning b efore starting work.Flight test equipment was also rudimentary,especially by today's standards. The "con trolroom" tor the X-1 flights, for exam ple, con-sisted of a small, mob ile van with a radarantenna on top of it and a radio in the office ofthe Chief of O perations.4

Living quarters for the NACA employ-

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oblem atic. Initially, thineers lived in a small,ases. The cluster of firetrap

alled visitor from t

is impracticable be-

miles away from the Muroc A rmy Airfield. Asa result, Walt W illiams, the head of the NAC Acontingent, was able to obtain permission fo rthe married NACA p ersonnel to move into theformer base housing there. The single NACA

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on a com plete series of X-p lanes froThere were not many women who cam e to the X-5, all of which would be flo

out to work at M uroc, but those who did ful- Muroc. Consequently, the NACA contifilled an important role in the research program. was m ade a permanen t facility, still unA co uple of them serve d as secretarylclerks, but Langley managemen t, known as the Nin those pre-automation days, someone with a Muroc Flight Test Unit.strong mathema tics background had to take the In 1949, Muroc was renamed Eraw data from flight instrumentation and con- Air Force Base, in memory of Captaivert it into a format the engineers could process. Edwards, an Air Fo rce test pilot wh oThe women who did that were known, even killed in the crash of a YB-49 Flying Withen, as "computers," and they were a respected That sam e year, the name of the NACA fac ilityand essen tial part of the resea rch team. was changed to the NACA High Speed Flight

Interestingly enoug h, both the women Research Station (HSFRS), underscoring theand men who worked at the Muroc station emphasis of the work the group was con duct-

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ing. Yet it remained a division of Langley until1954, when it was redesignated the NACAHigh Speed Flight Station (HSFS) and made anautonomous facility reporting directly to NACAheadquarters. That same year, the Station'semployees, who now numbered 250, movedinto new facilities halfway between the Southand North Bases. Those facilities have beenexpanded since that time, but they are still inuse today.6

To many people who worked at theHSFS, the 1950s were their golden years. Jetnoise, rocket sounds, and sonic booms shatteredthe desert air throughout the day, and NACA's

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"stable" was filled with exotic X-planes and Left. NACA Mur.oc unbarbecue, 1949new configuration fighters. Speed and altitude (NASAP I ~ O ~ O 4 902records were being set on a regular basis, andthere was a tremendous public fascination withthe activities at Edwards that grew as the X-planes reached higher and higher altitudes andspeeds. The Station's fame, prestige and prior-ity status at the NACA probably reached itspeak with the X-15 program, which made itsfirst flight in 1959, ust after the NACA becamethe National Aeronautics and Space Adminis-tration (NASA) and the space race began. Thatsame year, NASA renamed the Edwards stationonce again, redesignating it as the NASA Flight

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Research Center (FRC). Kennedy.of it s tow azrcraft, aStearwlarz biplane, onlakehed: Milt TIzoinpsoned in Paresev and, to hisright, a motorcycle withdriver who served ns thechase observer &iring l@u f c md low-level$ights,

(IVASAPhoto E 5713)

to keep the concep t of ae alive, FRC engineersh of lifting body shapes and

later contributed valuablepace Shuttle program, butiversally recognized at theX-15 program wound downe House Com mittee on

autics recommended thet Research Center, as "nond the X- 15would requiretion was proven wrong, but

FRC Director Paul Bikle thefly back from space had been put on the back danger of having the Center dependent on aburner in favor of a simpler ballistic capsule single research project. In 1963, Bikle's staffdesign and, with the Mercury mission s, more of compiled a 5-year plan for the Center thatNASA's resources and the nation's focus turned outlined a number of projects the Center couldtoward the space centers of Johnso n and pursue that would suppor t both the space



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program and the development of a Supersonic wing and winglet research, wingtip vortexTransport (SST). Fortunately, both of those analysis and a number of other research pro-programs were high national priorities in the grams. It was during this time that the Centerlate 1960s, and congressionalfunding for the was renamed once again, in honor of Hugh L.Center was kept intact.8

Th e late 1960s and1970s, then, saw theCenter diversifying intoseveral different researchareas-not only becauseBikle wanted to develop abroader base of research,but also because theCenter was receiving agrowing number of exter-nal requests for jointresearch efforts. In addi-tion to lifting body andLunar Module research to support the space Dryden, the internationally renowned aerody-program, the FR C conducted high-speed re- namicist who had been the NACA's Director insearch with the XB-70A and the YF-12 super- the FRC's early days. On March 26 , 1976, thesonic aircraft.At the same time, the Center Center became the Hugh L. Dryden Flightdelved into digital fly-by-wire, supercritical Research Center.

SR-71being worked onnight on ramp. Theaiwas one of three SR-71loaned toNASA by theForcefor use as high-high-altitude testbedsresearch in such areasaerodynamics,propulsstructures, thermalprotection materials, ainstrumentation. Datathe SR-71research procould aid designers offuture supersonic/hypersonicaircraft andpropulsion systems.(NASAPhoto EC92 31

Thispainting by Stan Sof theX-15 rocket aircpart of theNASA ArtProgram. Firstflown1959fromthe NASA HSpeed Flight Station(renamedtheNASA FlResearch Center thatyand the Dryden FlightResearch Center in 19the rocket-poweredX-1was developed toprovidata on aerodynamics,structures, reentrycharacteristics,heatinreaction and other lighcontrols, instrumentatand thephysiologicalaspects of high speed,altitude light. Three wbuilt by NorthAmericaAviation or NASA, theand theAir Force. Themade a total of 199fligduring a highly succesresearch program lastalmost tenyears. Theispeed and altitude recofor winged aircraftremained unbroken unSpace Shuttlefirst retufrom Earth orbit in 198(NASAPhotoEC94 42909-1)

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Despite its efforts to diversify, Dryden Arnes was actually one of several consolidationonce again faced a challenge when the YF-12 moves NASA made in 1981 in an effort toprogram ended in 1979.The number of employ- conserve money and resources. Combiningees was scaled back, and the Center was forced Dryden and Ames, it was reasoned, would

eliminate duplication ofmany administrativefunctions. Ye t regardlessof the reason, going froman autonomous facility toone that required Ames'approval for its activitieswas a difficult change forthe independently-mindedDryden employees toaccept. Part of the problemwas that having to obtainapproval from managers

to reevaluate its future direcuon. Then, while it over 300 mres away, who often went months

wingless, lifhng-bodyaircraft sitting on RogersLakebed are, rom leftright, the X-24A, M2-F3,HL-10. The lz@ng-bodyaircraft studied theof maneuveringlanding an aerodynamiccraft designed or reentryspace. Launched by amothership, the liftzngbodies lew, powered bytheir own rocket engines,making an unpoweredand landing. Theyvalidate the conceptSpace Shuttle couldmake safe, accurate,landings without power.(NASA Photo ECN 2359)was still in the process of redefining itself for without ever seeing the people they werethe needs of the 1980s and beyond, the Center supervising, slowed down the speed with whichwas hi t with another rough adjustment. Its projects could proceed. The Ames directors did

attempt to maintain the

ilexible and exploratory

communication style thatmanagers and employeesat Dryden had developedover the years, and they

No. 2 X-29 technolo)aircraft, lownby NASA's Dryden FlightCenter in a jointForce program toinvestigate the uniquedesign's high angle-of-characteristics and itsmilitary utility. Angle ofattack is the angle of anaircraft's body and wingsto its actual lightpath. This aircraft wasat Drydenfrom May1989 until August 1992.Photo EC90 0039-4)

I remained strong supporters

I of the flight researchDryden was conducting.I ut it was sometimesIifficult for off-site man-agers to understand theneed or importance ofsome of Dryden's activi-

status as an independent NASA center was ties or requests, and both communication andtaken away, and it was redesignated as a Flight management relations were hampered by theResearch Facility under the administration of 300 mile distancebetween the two facilities.the Ames Research Center near San Francisco. Nevertheless, the merger was the way of

Putting Dryden under the auspices of the world, at least for the time being, and the

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work at Dryden continued. In fact, the 1980 s toward independent operation, and in Marchsaw the dev elopme nt of the first significan t X- 1994, Dryden w as officially redesignated as anplane since the X- 15. In 1984, the radical autonom ous NASA Center.10forward-swept wing X -29 m ade its first flight. The move in part reflected NASA'sAnd if speed was pe rhaps less of a drive r than it recogn ition of the co ntinuing importance ofhad been, e specially in military aircraft design, flight research and the inva luable resources thatthere was a great deal still to be learned about Dryden's clear skies and open-desert surround-improving systems and making aircraft more ings provided. In fact, soon after Dryden wasmaneuverable and efficient. redesigna ted as a center, senior staff at NASA

Dryde n's w ork in the 198 0s included the began investigating the idea of movin g all ofbeginning of the High Alph a (Angle of Attack) the agen cy's aircraft and flight research activi-Research Vehicle (HARV) FIA-18 program, the ties to Dryden.Highly Integrated Digital Electronic Contro l But more than anything else, Dryden's(HIDEC) F-15 program, the A dvanced Fighter shift back to the status of an a utonom ous centerTechnology Integration (AFTI) F-16 project, reflected NASA 's recognition of the fact thatand the AFTI F -111N ission Adaptive Wing bigger was not always better. Left on its own,(MAW ) effort, as well as the Highly Maneuver- the sm all, sometimes irreverent center in theable Aircraft Technology (HiMAT) remotely desert could operate much like the innovativepiloted vehicle research. The facility also broke and effective "Skunk Works" that Kellyground in 1987 for a new $16.1 million Inte- Johnson had created for the Lockheed Corpora-grated Test Facility (ITF).g The new building tion in 1943. Dryden's particular mission,would include not only officespace designed for workingputerized aircraft; simulatoreven be connected to the actpits; and facilities for rapid aicheck-out and troubleshootinDryden would be better prepputer-driven information age,and on the ground.

By 1990, NASA heato the conclusion that Dryd eAmes for all its decision-mmore d ifficulties than it wasnumber of adm inistrative funcegated back to Dryden. The head position of the tasks at hand, so emp loyees got used toDryden was upgrad ed from a "site manager" to being flexible and performin g whatever job h ada "director" level, reflecting the increas e in to be done . The fact that it was small and notcontrol over the facility's activities. Over the easily accessible also meant that it had tonext four years, Dryden moved slowly back contend with less bureaucracy and politics than

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of a mere two pages of policies. The rest of itsfive volumes are simply procedures that offerguidelines based on what has worked withprevious Center projects.

The structure of Dryden's operatingmanual reflects not only a reliance on a humancorporate memory, but also a belief on the partof Center management in empowering itsemployees to simply "get the job done." If aproblem arises at 8:00 at night and the airplaneis scheduled to fly at 8:00 in the morning, themost important goal is to find a solution thatworks. In the minds of Dryden's managers, athousand procedures cannot cover the myriad ofcontingencies encountered in flight research aswell as the resourcefulness of employees chal-lenged and empowered to find creative solu-tions.

This attitude also creates an environ-ment where innovation and experimentation aremore likely to occur. The lifting body research,for example, started as a "backyard" project byseveral researchers who believed a craft couldbe flown back from space. Knowing it would bedifficult to get approval for a formal programthrough accepted channels, they went aboutproving the concept themselves first, with asmall amount of FRC money, a steel-tube-and-plywood wingless aircraft, and a souped upPontiac tow vehicle. The success of their designled to a formal research program which, in turn,significantly influenced the design of the SpaceShuttle. But without feeling that they had thefreedom to innovate; to venture ever so slightlybeyond the lines imposed by formal proceduresand programs, the researchers who instigatedthe lifting body effort would never even haveattempted the project.

This kind of support for individualinnovation at Dryden has endured over the

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years. And NASA supports this kind of grassroots effort by including a small "director'sdiscretionary fund" in centers' budgets to allowresearchers to explore concepts that might beoutside the scope of existing formal researchprograms, but which still might generate impor-tant results.12

All of these elements-this individualempowerment, a freedom to innovate, a staffaccustomed to being flexible and working onseveral projects at once, a long corporatememory, the informal management style al-lowed by the center's small size, and an ever-present focus on practical solutions-havecreated a unique atmosphere at Dryden that isparticularly well suited for flight research.These same elements have also given the centera capability described as "technical agility," orthe ability to adapt and adjust resources to meetconstantly changing needs. It is this quality thathas allowed Dryden to accommodate not onlychanging national research goals, bu t also theestimated 50percent of its research projectsthat are requests for help from other sources.13

ThePeopleWithout question, the facilities them-

selves and the Center's unique environmenthave played a big role in the contributionsDryden has made over the years. But another ofthe Center's most valuable resources has alwaysbeen its people.

From its very earliest days, it took aspecial kind of individual to work at the desertstation. Even today, with all the growth that hascome to the Palmdale and Lancaster communi-ties south of Edwards Air Force Base, a pro-spective employee is unlikely to choose Dryden

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because of its location. Fo r the past 50 years,I most of those who have come to work at theCenter have done so for one reason: they loveairplanes, and they want to do flight researchbadly enough that they are willing to live in theMojave desert in order to do it. The advantageof this fact, of course, is that Dryden's employ-ee s have always tended to be very dedicated totheir work.

The most visible of those employees-have always been the pilots. They are the oneswhose pictures appear next to the airplanes, the"Iron Men" of the rocket era who becameheroes to millions of American children. OneIeason pilots have always had such a highprofile is simply that they perform the mostvisible piece of the many elements involved inany research project. For all the sketches,calculations, wiring, and measurements that arecompleted ahead of each flight, the pilots arethe ones who actually climb into the hardwareand take it up in the air. But by the same token,the flight crews are also the only members ofthe research team who actually risk their livesto gain new knowledge or understanding.Some features of NACA/NASA pilotshave changed over the years. In the early days,

I although Dryden research pilots had Bachelorof Science degrees, they were more likely to be"stick and ruddery7men wh o knew more aboutflying than they did about systems and whotaught themselves the observation and reportingskills necessary for flight test or flight research.Today, NASA research pilots typically possess

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not only Bachelor of Science degrees, bu t also of the price sometimes exacted for progress inquite possibly Masters degrees, and have formal knowledge or aircraft designs. Pilots rarely talktest pilot school training or some equivalentexperience. Th e few pilots hired in recent

of danger or fear, bu t they do acknowledge risk."Tf we're doing something new, then by its very

historv at Drvdenwho had not alreadycompleted test pilottraining were sentthrough the AirForce school atEdwards Air ForceBase. As a result,current NASA pilots Itend to be moreknowledgeableabout systems andsystems safety than Ctheir predecessors Iwere.

Yet manyaspects of theresearch pilot's jobhave not changed.The job has alwaysrequired excellent,almost faultless,

Inature, we are stepping into arenas where weuse al l of these capabilities,al l of these tools, tominimize the risks and maximize the chance ofsuccess, bu t there are still elements there thatare unknown," says NASA research pilotRogers Smith.14

Thirty or forty years ago, the risks werehigher because computer ground test andsimulation technology was not nearly as ad-vanced. The X-15 pilots, for example, wereexploring altitudes and speeds far beyondanything that was known. No amount of windtunnel model testing could really predict whatan actual aircraft would do at Mach 6 or 50

flying skills. Fo r researchers to ge t the data theyneeded, the pilots need to be extremely precise

F-18 ittwluto~ ih4MEvans, imulation groleader,at thecontrolsin all of their maneuvers, because at the edges

of an aircraft's performance envelope or atspeeds of Mach 3 or Mach 6, there is littlemargin for error. In addition, no matter howthey got their training, the pilots have to be ableto observe and report the nuances and peculiari-ties of an aircraft's performance in clear, spe-cific terms.Being a research pilot also has alwaysentailed a certain degree of risk. Stree t names a tEdwards Air F orce Base that memorialize pilotswho didn't come back are a constant reminder

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miles above the Earth's surface. Not surpris- uncurl hi s toes. Some of the maneuvers requiredingly, the accident and pilot loss rate was also fo r test purposes would be more uncomfortablemuch higher thirty years ago than it is today. than most people could stand. A textbookYet the risk is always there. Despite al l the definition of an F-18 spin, fo r example, mightadvances in technology and simulation, an X-3 1 describe it as having "a medium yaw rate mode,

oscilliatory in al l three axes," with a note that "apost-stall gyration may occur." What this meansfo r the research pilot, however, is that he will bethrown about as if he were inside a washing7 achine, and after he stops the spin, the aircraftis likely to snap upside down suddenly andhang motionless in the air.16

I It takes a special kind of person to beboth able and eager to take on these kinds ofchallenges. Certainly, many different types ofpilots have climbed into Dryden's cockpits overthe years, bu t they seem to share several impor-

f researchers in research plane was still lost in January 1995.control rooin or rlze F-15researclz; John The pilot managed to eject safely, bu t he only

(o n right) and Gerard ha d approximately tw o-Scl~kolnik center)( NAS A Plzoto seconds to identify that a

EC93 42219-5) problem existed, gauge itsseverity, make a decision

techiziciai~Bill and punch out of therizakirzg a cannon plugaA Jirn Lewis looks on aircraft.15

Plzoto EC91 134-29) Even normaloperating circumstancesin research flying can beextremely challenging,both physically and men-tally. One of NASA's SR-7 1 pilots reported that hecould tell ho w proficienthe was in the Mach 3airplane by how long intothe flight it took him to

tant traits. Beyond simply being highly capable,confident, and observant, good research pilotspossess a driving curiosity fo r new challengesand knowledge that could be described as"technical passion." They want to learn what is



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beyond the limits of our current knowledge-badly enough that they are willing to take thecalculated risks and discomfort the journey mayentail. And while they all have undoubtedly hadmoments of anxiety or high tension, they focuson preparing well for each new challenge andhandling any contingencies in a professionalmanner. As veteran research pilot William H.Dana said, "I've been scared a few times flyingresearch missions, bu t my real fear was screw-ing up."17

This fear of not measuring up reflects apride in their profession that NASA's researchpilots all seem to share. "The flying we do is acraft," explains pilot Ed Schneider. "Yourhands, your brain, and your artistic talentliterally are combined together . . .and, like thePage 34

guilds in the middle ages, we pass that knowl-edge down to new pilots."l*

Ye t despite the visibility of their posi-tion, the research pilots are very aware that theyconstitute only on e element of the project team.A typical project will include research engi-neers, operations engineers, and a projectmanager, in addition to data systems engineers,technical and support staff. Research engineerswork on designing the experiments and analyz-ing the results, while operations engineers makesure the modifications will not compromise theintegrity or safety of the aircraft. The projectmanager is responsible for keeping the projecton schedule and budget and coordinates thevarious efforts and work tasks. These threeforces clearly have slightly different agendas,

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F-104 nose instrumenand technicians Keith(holding lashlight) anGaston Moore(NASA Photo EC911


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F-1Sflight.(NASA PhotoEC93 42219-Fr.2)

but they are designed tobalance each other to keepresearch efforts both on trackand safe. Indeed, staff mem-bers are so acutely aware ofthe red-life consequences ofany mistakes that they tend tobe very outspoken about theirviews. AS Dryden employeessay, "there are no secrets inflight research," There cannotafford to be. And any projectteam member, from researchengineer to the pilot himself,has the power to stop a fight ifhe or she feels them isasafety-of-fl;lg;ht issue leftunresolved.19

In addition, Dryden is such a smallfacility that most employees can see, wifhin oneor two steps, the direct impact of their efforts ona flyable &craft. This helps maintain t h ~ighmorale and enthusiasm that, in turn?make theCenter" "technical agility9'possible. Delayingan ongoing project to incorporate a new re-search effort can be ht rating; yet it is theability to reassign personnel according to needthat allow Dryden to conduct such a widerange of research with its relatively smallM.Seeing the tangible results of their efforts helpsstaff members cope with these kinds of b t s t a -tions. It also makes employeesmore aware ofthe fact that the efforts of many other peoplemay hinge on successful completion of theirparticular task. Consequently, when a problm@curs that could stop a scheduled flight thenext day, it is not unheard .of for researchers andtechnicians to work through the night to find asolution.2"

ThePartnershipsDryden" own employees are not the

only people whose dedication has been essentialto &e Center's contributions, however. Sincethe first group of engineers came to M m c withWalt Williams to support the Armyme11Air-craft/NACAX-1 effort, Dryden's research hasbeen characterized by partnerships. Some weref&ly simple pairings, involving only Drydenand a single contractor, or Dryden and anotherNASA center, Others-such as the X-1,X-15andX-29 projects-have invdved one or morecontractors, several NACALNASA centers, andone or more branches of the military.And theX-31program involved not only U.S. contrac-tors, the W.S. Navy, the U.S. Air Force, the~dvanced esearch Projects Agency (ARPA)andNASA, but the German Air Force and aGerman contractoraswell.

In a sense, the type of work Dryde~oesrequires partnerships. In many cases, Drydenhas been the last stop on an idea's journey from

The Right Stzff Page35


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m. That idea project. On the X-1, for example, the Arrny Airad different objectives.

ed to proceed methodicallyh data as possible, while the

forge ahead and conquer thes soon as possible.21 With th e X-

nd, the two organizations hadoals, which helped the

ership work more smoothly. In general,tnerships have seemed to work best when

mmo n objectives. If mem-at the program was m oving

r area of interest or expertise,ere more likely to occur.

when there are commonare still challenges to bership to be successful.

int efforts are not alwaysanizations' procedures

building. As a result, Dryden has always had and requirements do not always mesh. Success-ongo ing partnership s and relationships with the ful partnership s, therefore, require skillfulaircraft man ufacturing industry. Furtherm ore, negotiation, cooperation , and team-bu ildingthe fact that Dryd en is located on Edw ards Air efforts. Individu al relationships are critical, andForce Base and uses Air Force facilities on a many partnerships evolve from a rocky begin-regular basis has required an ongoing partner- ning to a point where the members have devel-ship between the Center and the Air Force. oped enough of a rapport and trust amongAlthough all of these relationships have themselves to develop procedures and ap-had their advantages and have allowed Dryden proaches that are agreeable to everyone. Teamto accomplish the work it has over the past half cooperation is so important that, as one Drydencentury, maintaining partnerships can be a manager said, "You draw up an organizationalchallenging task. NASA and the Air Force, for chart, but if you ever have to pull it out of theexample, have not only different agendas and drawer and actually look at it, you're inmissions but different operating cultures as trouble." W ith a partnership as complex as thewell. Over the years, both the Air Force Flight X-3 1,som e of the potential turf issues wereTest Center and Dryden have learned a lot diffused by consciously downplaying all indi-about work ing together, but creating and main- vidual identities in favor of an "X-3 1 team"taining a smoo th work ing relationship still identity. The partnership was also aided by therequires effort. fact that the new Integrated Test F acility (ITF)

In some ways, the success of a partner- at Dryden could house all the different teamship depends on the dynamics of the particular members in the same place. That close proxim-

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ity encouraged both ind ividual interaction and and concerns of those wh o will actually applyinform al problem solving, which helped the new techno logy. In addition, joint efforts helpteam ove rcome its significa nt organizational transfer new technology by strengtheningchallenges.22 individual relationships between NASA an d

Clearly, successful partnerships require industry or military personnel and cre atinga lot of work. But they a lso offer benefits that champions for new concep ts within organiza-

C. Williams ResearchIntegration FacilityIiztegmted Test

Facility) soon after theof the facility tothe fit-st director of whatthe Dryderz Flight

Research Center(NASA PhotoEC96 43393-1)

make the effort worthwhile. One obviousbenefit is that partnerships can supp ort projectsthat are beyond the capabilities of any oneorganization. But there are other advantages aswell. Through som e of its industry partnerships,for examp le, Dryden has found itself simulta-neously in the position of both teacher andstudent, learning about the practical ap plica-tions of technology as it shares its expertise indeveloping and testing new concep ts. Partner-ships also give Dryden 's researchers a real-world anchor and a "customer" orientation,helping them understand the needs, pressures,

tions or companies.Furthermore, if budg ets continue to

decrease and pressures to "downsize" increase,partnerships will undoubtedly become evenmore com mon. In 199 5, for exam ple, theDryden Fligh t Research C enter and the AirForce Flight Test C enter signed an Allianceagreement seeking to develop any and everyopportunity to cooperate and shar e resources,from a ircraft flight time and laborator y space toon-site child-care facilities.23



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ConclusionThe contributions the Dryden Flight

Research Cen ter has made to aeronautics andaerospace technology over the past half centuryhave been the result of many peop le's effo rtsand many factors that have helped mak e thoseefforts possible. Since its origins as a sm alldesert outpost of the Langley Laboratory,Dryden has been a unique place. Certainly itsphysical environment is unlike that at any otherNASA center. But its desert location andsingle-minded mission have also attracted acertain type of person and encouraged thedevelopment of a particular managem ent stylewell-suited to flight research.

Page 38

Without question, the physical surround-ings at Dryden are very importan t for its flightresearch activities. But the most valuable assetsat Dryden are not its open s kies or even itsaircraft, but its people. W ithout all the indi-vidual research team mem bers, the pilots, and aset of pragmatically minded managers, andwithout the ideas and efforts of its many part-ners, no flight research would have occurred. Itwas the unique combination of these factors-the Ce nter, its people, its particular manage-ment style , and its partnerships-that gaveDryden "the right stu ff' to m ake its manycontributions possible.

ReprintiarticlefDryden newthesummarlge of Drydeoccasiorenuming of thFlight RCenter in hon 26 Mar

Flights of Discovwy

Painting of Hugh L.for whom the DrydenResearch C enter waby Albert Murrayof New York.(NASA PhotoEC94 42724-1 )


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I i.. , , - . - , , I ,

50 Years of Flight ResearchDryden Flight Research Center ~ e d i c z o n eremonies, March 26,1976Thisyear wecelebrateDtyden'sanniversaryyca~: n Scientific Advisory G r o q headed by Dr. Theodorevonncognition o rhis event, theX-Press will reurint historical Karman.amcies, &res andphotoso evenrsin rhcpasr 50 years.Thefollowingiso nprinr o an anicle mm the Mac h Medal of F m d o m26. 1976edi~wn theX-Pms. commemoratin~he occasiono the dedication& m i n * o rheNASA ~lz;hr ~esearch V0n Karman's group produceda scries of reports, titledCenter in honor ofHughDryden, with slightcomctions or accuracy.Hugh LatimerDrydenknew OrvilleWrightand heknew John Glenn.Dr. Dryden was born inP o ~ m o k e ity. Maryland.on July 2.1898. He wasfive years old when theWrights titst flew off thedunes at Kill Devil Hill.Nonh Carolina. in 1903.Yean ater be was fond ofremarking, "the airplaneandI grew up together."In 1907 the Drydenfamily moved to Baltimorewhen young Dryden sawhis first airplane. He wasfascinatedby the birdlikesilhouette of the craft,but hewas not much impressedby

its performance.In 1913, at the ageof 14,he graduated from BaltimoreCity College. which in thatdav wasa hieh school He

collectively ~ h ; r eWeStand,and TowardNew Horizons.For his ccmibutions to thesereportsand by thedirectionof GeneralHenry H. "Hap"Amold, C b f of the U.S.Army AirForces, Drydenwas awarded the Medal ofFreedom. Years later, aftermany other awardshad beenreceived. Drydenremarkedthat he prized this awardabove all others.In 1946 Drydenbecame AssistantDirectorofthe Bureau of Standards,andsix months later he becamethe Bureau's AssociateDirector. Then in 1947 anew horizon of his ownsuddenlyappeared. Dr.George W. Lewis. Directorof AeronauticalResearchoftheNACA, was in failinghealth. and Dryden wasasked to succeedhim. In1949he was named to thenewly createdpost ofDkckOr of the NACAwint to oh& Hopkins HUGHL.DRYDEN -NASAFlight Reswch Centerphoto At the NACAUniversity o receivehis a9389 Dryden worked with othersbachelor'sdegree in tbrtt to find a solution to whatsears. which he took with honors in 1916. He went on to might be called "The GreatNationalWind Problem."

realms of physicsand mathematicshis faith experiencednoerosion;indeed it broadenedand deepenedover the years.He becam a licensed local preacherof the MethodistChurch.While many snentists and philosophershave whined andcried about "conttadictiou"be twan science and religion.Dryden foundno difficulty in achievinga durablesynthesisof the two. And when he spoke on the subjecthis auditorsw en inclinedto agree with him. He realized that we live inan imperfectworld populatedby imperf@ct en; andalthough it might be impossibleto achieveperfection n thisworld, it was incumbentupon everyoneto strive for the bestThe onors, officesand a+ bestowedupon Drydenwere great in their significanceand in number. A samplingmight include the Resident's Award for DistinguishedCivilian Service,the Lanalev Gold Medal of the SmithsonianInstirution. the Daniel ~ u i & n h e i mMedal, the WrightBrothersMemorial Trophy, the ElliotCresson Medal of theFranklinInstitute. the RockefellerPublic ServiceAward. theJohn Fritz Medal, and the RobertA. Goddard MemorialTrophy. He was h o n o d by election to honored foreignmember statusin the NationalAcademics of France andGermany, and to the aeronautical sociuics of Great Britainand Canada His hcnorary degrees. awarded n the UnitedStatesand ovenms. numbend 16.

Layman f the YearIn 1962 beMethodistUnion named Dryden theMethodistLayman of the Year. It was a distinctionthathe

cherishedevery bit as much as the many scientific p r i m andawards and all of the honorarydegnes that were bestowedupon him in his lifetime.Dryden was hospitalizedin Octoberof 1961for someweeks and exploratorysurgerydetermined hat he had anincurablemalignancy.Before he entend the hospital for theM ime, he keptbusy with conferences,meetings,and eotures. Drydenconcedednothing to his illness. He packed each day withgraduate school to receive his mastds degree in 1918. The %result was the Unitary Wind Tunnel P h hich saved more commiunentsand accelmted his schedule.titL of his mastds thesis was Airplanes: An lnmducfion ro millionsof dollars and millionsof man-hours of duplicating At 7:46 p.m. of Thursday. Dec. 2. 1965 High L.Drydenthe PkysicnlPrinciples Embodied in Their Use. effoort was no longer of this worldIn June of 1918. Dryden joined the staff of the National Ill these same years he played a key role in guiding palicy Dryden's career was devoted o solvingproblemsofBureau of Standardsas an inspectorof gauges. W i t h e and developmentof a g m t series of high speed reswmh iurbulence- n the realm of aeronauticsand in the affairsofencouragementof Dr. Joseph S. Ames. who at that timewas airpla~es hicb culminated n the X-15, an aircraft that me a As far as many one man's influence can be feIL he washcad of b e Departmentof by sics at Johns Hopkins,and amember of the newly createdNationalAdvisoryCommitteefor Aeronautics(NACA), Dryden obtaineda transferto theBureau's mm tl y mated wind tunnelsection. At the sametime Dr. Ames manged to give advancedcoursesfor anumber of Hopldns graduate6. This allowedDryden tocomplete bis doctoralr q u h m e n t s while being employedfull time.Youngestm.

Dryden receivedhis Ph.D. in physicsand mathematics nthe sprineof 1919. He wasonly 2Q~camoldandhemnainsthe &n&t studentever to have k e i v e d a%D. fromJohnsHopkins. The title of his thesis was AirForces onCircular Cylinders; in it he described experimentson thedrag and distribution of air flowingaround cylindersperpendicular o the wind.It was also in BaltimorethatDyden m a Mary LibbieTravus. OnJan.29,192Q hey were marriedIn the same ear Dryden became the head of the Bureau'sAmdynamics section,and continuedhis researchesonturbulence.In 1924, collaboratingwithLyman . Briggs,his mentorand Friend and later d innor of the Bureau,he m a d m e fthe earliestscientific investigationsof airfoil characteristicsat flowsup to the speed of sound- nd even slightly beyondIn a day when the fastestracing planes did well to fly at 280mp h hydm was already probing the transonic range ofsuprsonic flight.Since 1931 Dryden had been a member of the N A W sCommiueton Aerodynamics. and n 1934he became Chiefof the Bureau of StandardsbDivisionof MechanicsandSound.When the NationalDefense ResearchCommitteeand

almost became a spacecraftbyreachingthevery limits of theEarth's atmosphere. As missilespiercedthe atmosphere o hurtleout into space, Dryden pushed forsolutionstothectiticd mentryproblem.On Oc t 4,1957 the SovietUnion launchedintoorbit theworld's firstattitlcialEarth satellite,SputnikI.Congressand the White Houseimmediatelsmade plans of theirown to compete wiib the Russians.Theseolans included he cleation ofa civilian agency to conduct heexplorationof space. The NACAwas to be the nucleusof this newNationalAeronauticsand SpaceAdministration(NASA).

NASA fonnedT. Keith Glennan, presidentofthe Case Institute of Technology

was selectedto be the new agency'sAdministrator.Glennan insistedthat Dryden be NASA's Demtv~dm&trator. ~oge therhey -worked throughthenew agency'smost difficultyears.Dryden brougbt with him toNASA not only tbc oyalty of theNACA employees,but also the highregard in which he was held through(

inmdibly successfulon both accounts.The legacy ofDryden isdescribedhere in one of hissumons: "Noneofus knowswhat thefinaldestiny of manymay be,or if then sany a d o hiscapacityfor gmwtbandadaptation.Wherever his vennuel&us.Iamconvinced hat thepower to h v e heearth - to travel whucwe w i l l i n s p a c e dtoretunlatwill-marks the openingofa brilliantnew stagein man's evolution."Todsy's Events269 1976)Formal activitiestoday will begin witha ceremony n theUNVEILINGTBE UST- DuringPCenter dedication &'bration hangar.ceremonyon Mnrdr26,1976,Mrs.HughL.Drgden ~ v f i c in beunveils the bust of her bnsband wbieh isnow in the obby pmvided by theoIBl& 48W.NASAphotoECN 5137. AntelopeValleyHighSchoolSymphonic,ut the aeronautical Band. under the direction of Mr. JosephAcciani.I w r theOmceof SeientiticResearchand Development world. Among those addnssing the gathuing will beCmtm

(OSRD)wu c created n 194Q. Dryden took b e f one of When the White House finally chose James E. Webb to DirectorDr. David Scott. NASA AdminisuatorDr. James C.the O S W s guided missilesections. He was spekf idychargedwith the developmentd a adarguided W i e faerodynamiccharacteristics, or a glide bomb. For his workon theB W glidebomb) he received the PresidentialC e ~ M k p ef M u i t%den's work with OSRD marks his first experience nmaoagmg a lagensearch and developmentproject tiumconcept tohardware;and it marks the beg of the end ofhis original,mativc scientific camrand the start of hisadminismive camr. Concumntly with his work for theBurrau of Standards.OSRD and NACA, he was also heDeputy Dinctor, Scientific,of theU.S. A m ~ yir F o r m

become NASA's secondAdministrator, Webb replied that hewould accwt the wsition onlv on the mudition hat Drvdenmain as his depity. And sobryden remained untilbisdeath in 1965.Methodist Minister

A powerful factor in Dryden's life was his devotion o theMethodistChurch. He originally wanted to become aminister,but when he graduatedfrom high school at the ageof 14 he was ngarded as too young for acceptance n anydivinityschool. Although he found a second calling n the

Fletcher, SenatorFrank Moss, and T.Keith Glcnaan,firstAdministratorof NASA. Mrs. HughL ryda, guest ofhonor, will unveil a bust of h a husband, whicbwill evarm-ally be placed in the C e d s obby.After the ceremony,visitors w i i be invited to view astatic displayof aircraft n the main hangar. As of press date.aircraft scheduledtobe on display included hew-12,YC-IS. P 1 6 andF-17, X-24B and HL-10 lifting body. F-111TACT and IPCSaim& Firebeeand F-I5 RanotelyWotedR Vehicles,thetwoF-8DigitalPly-By-Wue andSupemiticalWing aircraR the full-size F-15, theMini-

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'exploratory" research conducted at the Dryden Flightpast half century, a good portion w as devoted to exp loring

at could not be tested safely at other NACAt of aircraft design from the late 19 40seasingly faster and higher-flying airplanes.

nology and advances to help m ake these goals pos-, s the renewed em phasis on high and fast flight in

significantly different from the initial work.gh Speed Civil Transport (HSCT) must meetironmen tal impact as well as speed and per-

formance . In the early days, the goals were less complex, and the focus was onpaving the way to supersonic flight and space.

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Breakingthe Sound Barrier

The most famous of all the researchprojects conducted at Dryden and its predeces-sor NACAINASA facilities in the MojaveDesert is probably the X-1-the rocket planethat first broke the infamous "sound barrier" inOctober 1947.

The X-1, a joint effort of the Army AirForces, NACA, and the Bell Aircraft Corpora-tion, was built to get answers about flight in thetransonic region (approaching and immediatelysurpassing the speed of sound) that researcherswere unable to get through conventional groundand wind tunnel tests. Aircraft design hadprogressed rapidly during World War 11,but ashigh-performance fighters such as the LockheedP-38 Lightning developed the capability of divespeeds approaching Mach 1, they began toencounter difficulties. Shock-wave, or "com-pressibility," effects could cause severe stabilityand control problems and had led to the in-flight break-up of numerous aircraft. Manypeople began to believe that supersonic flightwas an impossibility.

Clearly, more information about flightdynam

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