You can tell when a pilot has not yetmastered a Mooney manually operatedlanding gear: After takeoff, the wheelswill start to retract, then hang in trailwhile the pilot tries to wrestle the han­dle down to the floor. As the struggle inthe cockpit unfolds, the airplane beginsto porpoise because the pilot uncon­sciously hauls back and forth on thecontrol yoke for leverage. You can tellwhen a pilot has perfected the tech­nique: The gear disappears into thewheel wells in an instant. In experiencedhands, the Mooney manual gear may bethe fastest there is.

The manual gear was last used on theM20E Super 21, a model that bridgedthe simplicty of first-generation Moo­neys and the all-electric, higher-horse­power sophistication of later versions.The maturing process that has seen thefour-place Mooney M20 evolve fromwooden to metal wings, from 150 horse-

Manual flap, gearand turbocharging add

performance to thelow-maintenance systems

of an older Mooney.

BYMARK TWOMBLY

PHOTOGRAPHY BY ART DAVIS

power to 210 turbocharged horsepowerand from a short cabin to a stretched

fuselage also claimed the simple, ruggedMooney manual landing gear system.

The Super 21, introduced in 1964 andwithdrawn just three years later, was thefirst Mooney to have a 200-hp, fuel-in­jected engine and the last to incorporatemanually operated retractable landinggear and a mechanicaljhydraulic flapsystem. The original four-place M20Mooney, which appeared in 1955, waspowered by a 150-hp Lycoming 0-320.Mooney switched to a 180-hp Lycoming0-360 in 1958 with the introduction ofthe M20A, and continued to offer 180­

hp models through 1978. An electricallyactuated landing gear was first offeredas an option in 1965 and became stan­dard in 1969. That year, electrically ac­tuated flaps replaced the hand-pumpedhydraulic flap extension system.

There were 1,264 Super 21s produced

AOPA PilOT • 57

I

from 1964 through 1967. Sales droppedoff drastically in 1967, the first full yearof production for the M20F Executive.The Executive had the same LycomingIO-360-AIA engine as the Super 21, butwas 10 inches longer, held more fueland had a higher gross weight. Mooneydid not build any Super 21s in 1968, butin 1969 the M20E was reintroduced with

electric gear and flaps, a new instrumentpanel and power quadrant and a newname: the Chaparral. The short-cabinChaparral and long-cabin Executivewere co-produced until the Chaparralwas retired in 1975. Mooney undertookan extensive aerodynamic clean-up ofthe Executive during 1976, and the fol­lowing year introduced the model M20J,or 201. With no more horsepower thanthe Executive, the 201 was 19 knotsfaster and much more attractive. The lastof the Executives was sold in 1977.

Although not difficult to operate, theSuper 21's manual gear does requiresome effort on the part of the pilot. Italso takes up all of the space betweenthe two front seats, and space is a valu­able commodity in Mooneys. The sys­tem uses a direct mechanical linkage be­tween the long handle in the cockpit andthe welded steel-tube gear legs. To raisethe gear, the pilot depresses a safetylatch at the base of the instrument panel,slides the gear handle grip down to freethe bar from its down-lock, and pivotsthe handle down between the seats until

it locks into place.Mechanically raising and lowering the

gear does take a lot more effort thanflipping an electrical switch. The secretto operating the gear is to rotate the han­dle in one brisk, uninterrupted motion.Springs in the wings and fuselage takemost of the aerodynamic loads andweight off the gear handle. Once thehandle has moved through about half itsarc, the springs take over and the rest iseasy. With a little practice, the gear canbe retracted or lowered in less than two

seconds. Proponents of the manual gearsay it is difficult to forget to lower thegear because the handle is so prominent.

Extending the flaps is a two-step oper­ation. First, the pilot pushes down on anairfoil-shaped flap-position switch onthe panel to dose off the flap hydraulicsystem. Next, a stainless steel flap han­dle, located just to the right of the gearhandle, is pumped (twice for the takeoffsetting of 15 degrees, and four-and-a­half times for full flaps). Pumping thehandle moves a cylinder that pressurizesthe hydraulic system and forces the flaps

58· FEBRUARY 1986

MANUALMOONEY

Pump the flaps down,muscle the gear

up-operating the systemtakes a lot of work.

to extend. When the position switch isreturned to Up, springs and air pressureslowly retract the flaps.

The manual labor required to operatethe gear and flaps is more than offset bythe reliability of the simple systems.Both systems have a reputation for inex­pensive and infrequent maintenance,but overhaul kits for the flap system nolonger are available. Mooney Aircrafthas an electric retrofit kit for the manualflap system that costs $632 and takes anestimated 20 man-hours to install.

The Super 21 featured in these photo­graphs was manufactured in June 1964and initially was used by Mooney Air­craft as a model for publicity photo­graphs and as an experimental proto­type to test changes that were officiallyintroduced in the 1965 model year. Itwas the first Mooney equipped with anew squared-off window and a BrittainIndustries, Incorporated, wing-levelingdevice called Positive Control (PC).

Pneumatic pressure supplied by theengine-driven vacuum pump powersservos linked to the ailerons and rudder.

The single-axis (roll) autopilot is en­gaged as long as the engine is running,but the pilot can momentarily overridethe wing-leveler by depressing a button

on the control yoke. PC was standardequipment on the Super 21 beginning in1965. Some pilots found the PC annoy­ing when maneuvering and devisedways to disconnect it. The system alsohad to be well maintained, since pinholeleaks in the pneumatic servos wouldcause sluggish performance.

Dr. Paul M. Straub, AOPA 467411, ofRolling Hills, California, boughtN300MD in 1970. (Straub changed theoriginal registration number fromN7121U to N300MD.) When the Moo­ney's engine was overhauled in 1975,Straub had a Rajay turbocharger kit in­stalled. The turbocharger enables theLycoming IO-360-A1A engine to de­velop maximum continuous power to20,000 feet, according to Century Air­craft Corporation (Post Office Box31026, Amarillo, Texas 79120), whichmanufactures and markets Roto-Master,Incorporated, (formerly Rajay) turbo­charger kits for a variety of piston sin­gles and twins. The wastegate valve isadjusted manually with a large verniercontrol partially hidden between thebottom of the instrument panel and thetop of the nosewheel well.

There are a few caveats that must be

heeded to avoid overboosting the en­gine. The aircraft is placarded againstoperating the turbocharger below 3,500feet. From 3,500 to 12,000 feet, there is athree-minute limit on use of takeoff

power, which is 28.5-inches manifoldpressure and 2,700 rpm. Maximum con­tinuous power to 20,000 feet is 27 inchesand 2,500 rpm, and from 20,000 to25,000 feet the limits are 25 inches and

2,500 rpm. The pilot must apply fullthrottle before engaging the turbo­charger and open the wastegate duringdescent to prevent overboosting as theair becomes more dense.

The flight manual supplement forN300MD does not contain performancecharts for altitudes above 15,000 feet,where the turbocharger is most produc­tive. Specifications published by Cen­tury Aircraft Corporation claim that aturbocharged Mooney M20E has a criti­cal altitude of 16,500 feet, a service ceil­ing in excess of 30,000 feet and willcruise at 195 knots at 20,000 feet and 75­percent power. At 12,000 feet and 75­percent power, it should cruise at 174knots, and, at 10,000 feet, 168 knots,according to Century.

We did not have the opportunity totest the high-altitude performanceclaims, but at lower altitudes, from 6,500to 14,500 feet, true airspeeds fell short of

AOPA PILOT • 59

the pilot operating handbook figuresand Century's figures by about eight to10 knots. Although the turbochargerhad recently been overhauled, Straubsuspected there were leaks in the systemthat caused a loss in power.

Despite having a reputation as a high­maintenance item, the turbocharger hasheld up well in N300MD. The overhau]is the only major service the system hasrequired since it was installed, accordingto Straub. However, the turbocharger isshoehorned into an already tight enginecompartment in the Super 21, whichmakes it that much more difficult to

work on the engine.The Century turbocharger kit costs

$7,590 uninstalled and adds 16.5pounds to the empty weight of the air­craft. The only external change requiredon the aircraft is the addition of a lou­

vered panel on the right side of the en­gine cowling. An aftermarket turbo­charger modification mayor may notadd to the value of a 20-year-old Moo­ney. A pilot looking for high perfor­mance on a budget would do well toconsider a turbocharged Super 21. Onthe other hand, the long-time owner of aMooney sales and service center in thenortheastern United States said he hasknown several customers who over­

boosted their turbocharged engines andsuffered the repair consequences. In hisopinion, a turbocharger does not in­crease the price of an older Moone}Normally aspirated Super 21s are worthfrom $20,000 to about $22,500, accord­

ing to the latest Aircraft Bluebook PriceDigest, but the condition of the avionics,paint, interior and engine have a signifi­cant effect on the value.

When it was new, the turbochargergave Straub's Super 21 additional speed

60· FEBRUARY 1986

MANUALMOONEYMechanical systems

blended with 200 hp­performance made theshort-body Super 21 a

simple sophisticate.

and high-altitude capability, but herarely used it on his many long-distanceflights. If maximum range was the ob­jective, Straub would cruise at between12,000 and 14,000 feet with the powerset at 16 inches and 2,400 rpm. Hefound adventure and relaxation in longtrips, and the longer, the better.

Straub traded up to the Super 21 froma Piper Tripacer. The Mooney's greaterspeed and range made it far more adeptat tackling the Friday-night-to-Sunday­night flights Straub regularly made fromhis home in Johnstown, Pennsylvania,to the Bahamas. With the Mooney, hebegan to plan more ambitious flights toHaiti, Jamaica, the Virgin Islands andinto South America. In December 1970,Straub flew from Pittsburgh to Caracas,Venezuela, to climb Angel Falls in thejungles of southeast Venezuela. The3,282-foot-high waterfall is reputed tobe the highest in the world. The success­ful expedition was chronicled in a book,Angels Four, written by David Nott, oneof the four climbers (Prentice-Hall, In­corporated, Englewood Cliffs, New Jer­sey, 1972).

In 1975, Straub replaced the Moo­ney's rear seats with a 55-gallon drum

and lashed a second auxiliary fuel tankto the right front seat. He planned to flynonstop from Gander, Newfoundland,to the European continent, but afterreaching Gander the flight plan had tobe changed because of a low-pressuresystem that had stalled over the AtlanticOcean. He flew south, instead, to theAzores, and then on to Portugal, Spainand Western Europe. The last leg of thereturn trip to the United States was a 21­hour nonstop flight from Reykjavik, Ice­land, to John F. Kennedy Internationalin New York City. Straub then flew tothe Reading Air Show in Reading, Penn­sylvania, where N300MD was namedthe best production single-engine re­tractable of the show.

The following year, Straub made asecond flight to and around Europe. Inthe summer of 1977, he flew around theworld. The trip began in Wichita, wherea larger rear-seat auxiliary fuel tank wasinstalled, giving the Mooney a total fuelcapacity of 199 gallons. Survival gearwas squeezed between the front tankand the instrument panel, and the pilot'sseat could be reached only by wigglingbetween the top of the tank and thecabin roof.

When all of the tanks were filled, 15

pounds of lead shot had to be placed inthe engine compartment to keep thecenter of gravity within limits. The en­gine was fresh from a major overhaul,and the cockpit had been outfitted withdual automatic direction finders (ADFs),a high-frequency communications ra­dio, three-axis autopilot, an oil-pressurewarning horn and a rented Loran-A re­ceiver. Fully loaded, N300MD was 25percent over gross weight, which theFAA approved under a waiver.

Straub departed Wichita for Gander

The tight quarters underneath the cowling were made even tighter when the turbocharger was

installed. The modification includes changes to the intake and exhaust systems.

Mooney M20E Super 21Specifications

Lycoming IO-360-AIAwith Rajay Rj0326-1 turbo­

charger, 200 hp @ 2,700 rpmRecommended TBO 1,800 hr

Propeller Hartzell HC-C2YK-IA/7666A-2 74-inch diameter

23 ft 2 in8 ft 4 in

35 ft

167 sq ft15.4 lb/sq ft

12.9Ib/hp4

8 ft 8 in

3 ft 4.5 in3 ft 8.5 in

1,642 Ib2,575 Ib

9331b6211b

312lb (3121b usable)52 gal (52 gal usable)

8 qt120lb

(plus to lb in hat rack)Performance

Takeoff distance, ground rollTakeoff distance over 50-ft obstRate of climb, sea level

Max level speed, 2,500 ft

with the tanks partially full, then flewnonstop to Karlsruhe, West Germany,and on to Athens, Greece; Ankara, Tur­key; Teheran, Iran; Karachi, Pakistan;Calcutta, India; Bangkok, Thailand; andSingapore. He had planned to spendtwo months on the flight, but in Singa­pore he learned of an illness in his fam­ily and rushed through the rest of hisitinerary. After stopping at several Aus­tralian cities, Straub flew to Fiji andPago Pago in West Samoa. The next legwas the longest overwater segment ofthe trip: 2,171-nm to Honolulu. All ofthe fuel tanks were topped for the firsttime since leaving Wichita, and Straubwaited until evening and cooler tem­peratures to take off from Pago Pago.The Mooney broke ground in less than athird of the length of the 9,DDD-foot run­way, and Straub reached Hawaii with­out having to draw from the main tanks.

With the tanks full once again, Straubdeparted Honolulu for the continentalUnited States. He overflew San Fran­

cisco and reached Salt Lake City beforeswitching to the main tanks. The in­tended destination was Cedar Rapids,Iowa, but the weather there was belowminimums. Straub elected to land at DesMoines, 27 hours two minutes afterleaving Hawaii, with two hours fuel stillin the tanks.

Six months after completing the trip,Straub and his wife, Toni, flew N3DDMD

to Europe and back. That was the Moo­ney's last ocean crossing and one of itsfinal long flights. Following a trip to theBahamas, the airplane was left in Floridafor repairs, including an overhaul of theturbocharger system. Meanwhile,Straub, a specialist in hair transplanta­tion, moved his practice from Johnstownto Los Angeles. The Mooney remainedbehind in Florida and for several yearswas flown very little.

A year ago, Straub retrieved the air­plane, had it repainted and now bases itat the Torrance Municipal Airport inTorrance, California, near his home and

offices. The oil-pressure warning hornand aging ADFs are the only remindersof the global travels of a decade ago.Straub and his wife and young son takeoccasional overnight flights, but theyhave not yet ventured far from Torrance.The urge to prowl the world in a lightaircraft has been held in check by thedemands of a successful medical prac­tice and a young family, but Straub hasnot ruled out a long-distance flight ortwo in the future. The auxiliary fueltanks still are stored in his garage. 0

Powerplant

LengthHeightWingspanWing areaWing loadingPower loadingSeats

Cabin lengthCabin width

Cabin heightEmpty weightGross weightUseful load

Payload w/full fuelFuel capacity, std

Oil capacityBaggage capacity

760 ft

1,300 ft

1,120 fpm171 kt

Max level speed, 20,000 ft 195 ktCruise speed/Range w/no rsv, std fuel(fuel consumption)

@ 75% power, best economy5,000 ft 158 kt/771 nm

(64 pph/tO.6 gph)@ 65% power, best economy

7,500 ft 152 ktf 844 nm(56 pph/9.4 gph)

@ 55% power. best economytO,OOOft 142 kt/897 nm

(50 pph/8.3 gph)Max operating altitude 30,000 ftLanding distance over 50-ft obst 1,550 ftLanding distance, ground roll 595 ft

Limiting and Recommended AirspeedsVx (Best angle of climb) 80 KIASVy (Best rate of climb) 98 KIASVa (Design maneuvering) 115 KIASVfe (Max flap extended) 87 KIASVie (Max gear extended) t04 KIASVlo (Max gear operating)

Extend 104 KIASRetract 104 KIAS

Vno (Max structural cruising) 130 KIASVne (Never exceed) 164 KIASVsl (Stall clean) 58 KIAS

Vso (Stall in landing configuration) 50 KIASAll specifications are based on manufacturer's

calculations. All performance figures are based

all standard day, standard atmosphere, at sea

level and gross weight, unless otherwise noted.

AOPA PILOT • 61