The
Mooney M20 is a family of
piston-poweredA reciprocating engine, also often known as a piston engine, is a heat engine that uses one or more reciprocating pistons to convert pressure into a rotating motion. This article describes the common features of all types...
, propeller-driven
general aviationGeneral aviation is one of the two categories of civil aviation. It refers to all flights other than military and scheduled airline and regular cargo flights, both private and commercial. General aviation flights range from gliders and powered parachutes to large, non-scheduled cargo jet flights...
aircraftAn aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
, all featuring a low-wing and
tricycle gearTricycle gear describes an aircraft undercarriage, or landing gear, arranged in a tricycle fashion. The tricycle arrangement has one wheel in the front, called the nose wheel, and two or more main wheels slightly aft of the center of gravity...
, manufactured by the
Mooney Airplane CompanyThe Mooney Aviation Company, Inc. is a U.S. manufacturer of single-engined general aviation aircraft. Mooney has been a leader in civil aviation even though the company has gone bankrupt and changed ownership several times...
.
The "M20" was the twentieth design from Al Mooney, and his most successful. The M20 series was produced in many variations over the last 50 years, from the wooden wing M20 and M20A models of the 1950s, to the M20TN Acclaim that debuted in the 21st century.
On 5 November 2008 the company announced that it was halting all production as a result of the late-2000s recession. As of October 2011 production has not resumed.
Development
The Mooney M20 series has been produced in three fuselage lengths: the "short body", "medium body" (including M20J), and "long body" types. Although all M20s have four seats, the fuselage length increase provided more passenger legroom but with a slight performance decrease. Other airplane improvements over the years more than compensated for the effects of a longer fuselage.
In July 2008 Mooney signed a memorandum of understanding with
Rolls-RoyceRolls-Royce Group plc is a global power systems company headquartered in the City of Westminster, London, United Kingdom. It is the world’s second-largest maker of aircraft engines , and also has major businesses in the marine propulsion and energy sectors. Through its defence-related activities...
to develop a version of the M20 that was to have been powered by the
Rolls-Royce RR500-References:* Flying , Vol. 135 Issue 11, Nov. 2008, p. 32, "Rolls-Royce Launches Turboprop for Small Airplanes"-External links:*...
TP
turbopropA turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
powerplant. The project was announced as being a joint "marketing investigation" and "exploration project" but does not appear to have come to fruition.
Design
With the exception of the wooden wing spars of the original M20 and M20A, M20s are all-metal, low-wing aircraft. The wings are of
cantileverA cantilever is a beam anchored at only one end. The beam carries the load to the support where it is resisted by moment and shear stress. Cantilever construction allows for overhanging structures without external bracing. Cantilevers can also be constructed with trusses or slabs.This is in...
construction, consisting of a main spar and an auxiliary spar that extends from the fuselage to the mid position of the
flapsFlaps are normally hinged surfaces mounted on the trailing edges of the wings of a fixed-wing aircraft to reduce the speed an aircraft can be safely flown at and to increase the angle of descent for landing without increasing air speed. They shorten takeoff and landing distances as well as...
. The wing skin is aluminum which is flush riveted in many areas to reduce parasitic drag. Slotted flaps cover 70% of the trailing edge. Early models use a hydraulic hand pump to control the flaps while later models have electrically operated flaps. The forward fuselage has a steel tube cabin structure covered in aluminum skin, while the aft fuselage is of semi-monocoque design.
The tricycle undercarriage legs of the Mooney M20 models are made of heat-treated chrome-molybdenum steel. The main gear legs are attached to the main wing spar, while the nose gear is mounted onto the steel cabin frame. Rubber discs, as well as spring steel, around the legs allow for compression and shock absorption on landing. Except for the fixed-gear M20D, the nose wheel retracts rearward and the main wheels towards the fuselage. Early models use a hand-operated lever system to raise and lower the gear. Later models use an electrically operated landing gear retraction system with a backup crank-operated or wire-pull gear extender.
The Mooney M20 has medium
aspect ratioIn aerodynamics, the aspect ratio of a wing is essentially the ratio of its length to its breadth . A high aspect ratio indicates long, narrow wings, whereas a low aspect ratio indicates short, stubby wings....
tapered wings, incorporating 1.5° of
washoutWashout refers to a feature of wing design to deliberately reduce the lift distribution across the span of the wing of an aircraft. The wing is designed so that angle of incidence is higher at the wing roots and decreases across the span, becoming lowest at the wing tip...
and 5.5° of dihedral. On the M20J, navigation and anti-collision lights are located inside an aerodynamically designed cover at the wingtips to further eliminate drag. Later M20s are equipped with
stall stripsA stall strip is a fixed aerodynamic device employed on fixed-wing aircraft to modify the airfoil used. They are usually factory-installed or, on rarer occasion, an after-market modification. Stall strips are almost always employed in pairs, symmetrically on both wings...
to improve the
stallIn fluid dynamics, a stall is a reduction in the lift coefficient generated by a foil as angle of attack increases. This occurs when the critical angle of attack of the foil is exceeded...
characteristics.
The
empennageThe empennage , also known as the tail or tail assembly, of most aircraft gives stability to the aircraft, in a similar way to the feathers on an arrow...
of the Mooney M20 is easily recognizable by its unique tailplane with a vertical leading edge. (The tail looks like it is "leaning forward", but it is actually straight vertical.) The horizontal tailplane, which consists of a fixed stabilizer and trailing elevator, has no trim tabs. The entire tail assembly pivots at the rear of the fuselage to provide for pitch trim.
All M20s store fuel in two separate "wet wing" tanks, which are located in the inboard sections of each wing. Fuel is driven from the tank to the injectors or carburetor by an engine-driven pump, backed up with an electric boost pump.
For increased power many M20s also have a
ram airA ram air turbine is a small turbine that is connected to a hydraulic pump, or electrical generator, installed in an aircraft and used as a power source...
system called the Mooney "Power Boost". For normal operations the intake air is filtered before it enters the induction system. When ram air is selected, partially unfiltered air will enter the induction system with a higher pressure and consequently the manifold pressure will increase about a full inch when flying at 7500 msl, giving a greater power output. The turbocharged variants omit this feature as they have their own "power boost" that provides far more increase in manifold pressure.
Variants
M20 and M20A
- The original M20 (1955–1958) and the M20A (1958–1960) have wings made of wood and covered with cloth, but are otherwise similar to later all-metal models. With the M20A, the power was increased from the M20's 150 hp Lycoming O-320
The Lycoming O-320 is a large family of 92 different normally aspirated, air-cooled, four-cylinder, direct-drive engines commonly used on light aircraft such as the Cessna 172 and Piper Cherokee. Different variants are rated for 150 or 160 horsepower...
to the 180 hp Lycoming O-360-A1A or A1D.
- Early in the model's history there were several incidents of wooden tails breaking up in flight due to water damage and the resulting rot. Consequently, most tails have now been replaced with all-metal copies, as required by Mooney Service Bulletin M20-170A and the FAA Airworthiness Directive
An Airworthiness Directive is a notification to owners and operators of certified aircraft that a known safety deficiency with a particular model of aircraft, engine, avionics or other system exists and must be corrected....
86-19-10. Without the possibility of metal fatigue, the wooden wing has an indefinite life expectancy and is considered by some pilots to provide a smoother ride in turbulence.
- The M20 received its type certificate
A Type Certificate, is awarded by aviation regulating bodies to aerospace manufacturers after it has been established that the particular design of a civil aircraft, engine, or propeller has fulfilled the regulating bodies' current prevailing airworthiness requirements for the safe conduct of...
on 24 August 1955 with the M20A following on 13 February 1958.
M20B
- Mooney addressed the dwindling supply of woodworkers by switching to an all-metal design in 1961 with the M20B. The all-metal design added some weight and cost 5 to 8 knots (9 to 15 km/h) in top end speed versus the wood-wing models. There have been no reported in-flight breakups of all-metal M20s other than as a result of flight directly into a thunderstorm.
- The M20B was type certified on 14 December 1960 with the 180 hp Lycoming O-360-A1A or A1D engine.
M20C
- In 1962 Mooney made further incremental improvements in the M20C Ranger, produced between 1962 and 1978.
- The M20C was the last short body Mooney in production, with more M20Cs produced than any other Mooney model.
- The M20C was type certified on 20 October 1961 with the 180 hp Lycoming O-360-A1A or A1D engine.
M20D
- In 1963 Mooney introduced the M20D Master, essentially an M20C with fixed gear and a fixed-pitch propeller.
- The M20D was type certified on 15 October 1962 with the 180 hp Lycoming O-360-A1D or A2D engine.
- The aircraft was intended primarily for flight training and for owners seeking lower insurance rates.
- The M20D lasted in production only until 1966. Most have now been converted to M20Cs for increased cruise speed and climb performance.
M20E
- The first truly high performance Mooney, the M20E, was produced from 1964 to 1975 and marketed as the Chaparral and Super 21.
- The M20E was essentially an M20C with a more powerful 200 hp fuel-injected engine. It was type certified on 04 September 1963 with the 180 hp Lycoming O-360-A1A engine.
- This short body Mooney still has the distinction of having the shortest takeoff runway requirement at lower elevations.
- Turbocharging, which would maintain this performance at higher elevations, is available as an after-market option.
M20F & M20G
- Mooney stretched the fuselage and initially added a third fuselage side window with the M20F Executive 21, which was produced between 1966 and 1977. The M20F is otherwise similar to the M20E.
- The M20G Statesman, produced 1968–1970, was a stretched M20C incorporating the carburated 180hp engine. Many M20G owners later converted to the 200hp engine.
- In 1969 Mooney made electrically operated landing gear and flaps standard across all its aircraft. Prior to that, pilots extended and retracted the standard landing gear using a heavy metal Johnson bar. Electrically extended landing gear was an option.
- The M20F was type certified on 25 July 1965 with the 180 hp Lycoming O-360-A1A engine, with the M20G following on 13 November 1967, equipped with the with the 180 hp Lycoming O-360-A1D engine.
M20J
- Mooney hired Roy LoPresti
LeRoy Patrick "Roy" LoPresti was an eclectic American aeronautical engineer. He worked on projects as diverse as the Apollo Moon Program and missile design, served as advisor to the US Congress, became known as "Mr...
to undertake an aerodynamic cleanup of the M20F, resulting in the 1977 model year debut of the M20J. The M20J was marketed under the name Mooney 201 because of its 201 mi/h top speed in level flight. The M20J first flew in September, 1976 and was type certified on 27 September 1976. It is equipped with the with the 200 hp IO-360-A1B6D, -A3B6D or -A3B6 engine.
- The improved aerodynamic shape and updated 200 hp engine made the M20J the second most popular variant of the M20 series, after the M20C. It is often used as a training aircraft for commercial pilots. It was originally designed as a private/commercial touring aircraft because of the high cruising speed and relatively low operational cost. This model was marketed as the Mooney 205. The J model had a long production run, lasting until 1998, thus ending the medium body M20 series.
M20K
- Up through the M20J all Mooney M20s had four-cylinder Lycoming engines. After designing the M20J, Mooney modified the basic design to include a variety of more powerful six-cylinder engines, including some models with turbocharged
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
engines. The first such design was the turbocharged M20K, which was produced between 1979 and 1998.
- The M20K was marketed as the Mooney 231. This model's Continental TSI0-360-GB engine was challenging to operate at acceptable engine temperatures, so by 1986 it was replaced with an intercooled engine, eliminating the temperature problems and achieving a top speed of 252 mi/h in level flight (at FL 280). This variant was marketed as the Mooney 252.
- The M20K was type certified on 16 November 1978. It is equipped with the with the Continental TSIO-360-GB1
The Continental IO-360 is a family of fuel-injected air-cooled, six-cylinder aircraft engines manufactured by Continental Motors in the United States of America, now part of the Teledyne corporation, since 1962....
-GB3, -GB4, -LB1, -MB1, -MB2 or -SB2 engines. All produce 210 hp, expect the -MB1 and 2 and the SB1 which produce 220 hp.
M20L
- In 1988 Mooney went to even greater lengths, partnering with Porsche to include their geared single-lever Porsche PFM 3200
Porsche's PFM 3200 was a six-cylinder horizontally opposed air-cooled aircraft engine developed from their air-cooled line of automobile engines from the famous Porsche 911 sports car...
N03 engine of 217 hp and stretching the fuselage the last time to produce the first long body M20. Most M20Ls no longer use this unique engine. M20L production ended in 1990. This model was marketed as the Mooney PFM.
- The M20L achieved type certification on 25 February 1988.
M20M
- The M20M (1989–2006) boosted output initially to 270 hp and was also turbocharged. The M20R (1994–) started at 280 hp and was normally aspirated. With minor changes in engine output (e.g. the M20S "Eagle") and various performance tweaks, these two basic models (both high power, both with long bodies, one with turbocharging) remain in production today as the "Bravo" and "Ovation".
- The M20M was type certified on 28 June 1989 and is equipped with the 270 hp Lycoming TIO-540-AF1A
|-Specifications :-See also:-External links:...
or -AF1B.
M20R
- Introduced in 1994, the M20R Ovation mated a long body fuselage to a Continental IO-550-G
The Continental IO-550 engine is a large family of fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors...
normally aspirated powerplant of 280 hp. This model was named Flying Magazine'sFlying is an aviation magazine published since 1927 . It is read by pilots, aircraft owners, and aviation-oriented executives in business and general aviation markets worldwide....
single-engine plane of the year in 1994.
- The M20R was type certified on 30 June 1994 and is equipped with the 280 hp Continental IO-550-G(5)
The Continental IO-550 engine is a large family of fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors...
, -G(6) or -G(7) engine.
M20S
- The M20S Eagle was introduced in 1999 and was powered by a Continental IO-550-G engine of 244 hp. In 2001 the Eagle 2 was introduced. This model included such refinements as a 3-bladed propellor, a 100 lb (45.4 kg) gross weight increase and standard leather interior.
- The M20S was type certified on 07 February 1999 and is equipped with the 244 hp Continental IO-550-G(6)
The Continental IO-550 engine is a large family of fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors...
engine.
M20T
- The M20T Predator, a canopy-equipped version of the basic M20 design powered by a Lycoming AEIO-540
|-Specifications :-See also:-External links:...
engine, was Mooney's entrant in the USAF Enhanced Flight Screener competition. The prototype was built in 1991 and displayed in tiger-stripe paint scheme. The contract was won by the ill-fated Slingsby T-67 FireflyThe Slingsby T67 Firefly, originally produced as the Fournier RF-6, is a two-seat aerobatic training aircraft, built by Slingsby Aviation in Kirkbymoorside, Yorkshire, England...
and the M20T was not developed or certified. The sole prototype, registered N20XT, was flown in the Experimental - Market SurveyAn experimental aircraft is an aircraft that has not yet been fully proven in flight. Often, this implies that new aerospace technologies are being tested on the aircraft, though the label is more broad....
category and was still owned by Mooney Aircraft in 2008.
M20TN
- The M20TN Acclaim was the last version of the M20 design produced and is powered by a turbo-charged Continental TSI0-550-G
The Continental IO-550 engine is a large family of fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors...
powerplant with twin turbochargers and dual intercoolers. The Acclaim replaced the Mooney M20M Bravo in the company product line.
- The M20TN was type certified on 15 October 2006 and is equipped with the 280 hp TSIO-550-G(1)
The Continental IO-550 engine is a large family of fuel injected six-cylinder, horizontally opposed, air-cooled aircraft engines that were developed for use in light aircraft by Teledyne Continental Motors...
, -G(2), -G(3) or -G(4) engine.
Modifications
Mooneys derive their performance from a clean airframe with drag reduced by refinements over the years. Many of these refinements are
Supplemental Type CertificateA Supplemental Type Certificate is an FAA approved major modification or repair to an existing type certified aircraft, engine or propeller. As it adds to the existing type certificate, it is deemed 'supplemental'.-Purpose:...
(STC) modifications to the airframe developed by after-market businesses. Some of these modifications have been incorporated into the factory production models.
Rocket 305
In 1990, Rocket Engineering Corp. of
SpokaneSpokane is a city in the U.S. state of Washington.Spokane may also refer to:*Spokane *Spokane River*Spokane, Missouri*Spokane Valley, Washington*Spokane County, Washington*Spokane-Coeur d'Alene-Paloos War*Spokane * USS Spokane...
, Washington, modified a M20K 231 model by replacing the standard turbocharged 210 hp
Continental TSIO-360The Continental IO-360 is a family of fuel-injected air-cooled, six-cylinder aircraft engines manufactured by Continental Motors in the United States of America, now part of the Teledyne corporation, since 1962....
engine and 2-blade prop with a turbocharged 305 hp Continental TSIO-520-NB and a McCauley 3-blade propeller. This engine and propeller combination had been previously proven on the twin-engined
Cessna 340|-See also:-References:* Taylor, John W. R. Jane's All The World's Aircraft 1982–83. London: Jane's Yearbooks, 1982. ISBN 0 7106-0748-2.* Taylor, John W. R. Jane's All The World's Aircraft 1988–89. Coulsdon, UK: Jane's Defence Data, 1988. ISBN 0 7106-0867-5....
and
Cessna 414. Marketed as the Rocket 305, this variant delivered a 228 knots speed and 1,600 feet/minute rate of climb. This significantly increased performance, but at the expense of higher fuel burn.
The 305 Rocket STC represented a year certification effort, including 1,000 flight test hours. The 305 Rocket passed all FAA flight test requirements including spin, flutter, load, cooling and noise tests. The STC covered both the 231 and 252 M20K variants. While the 231 and 252 had a maximum certificated altitude of 24,000 ft (7,300 m) and 28,000 ft (8,500 m) respectively, the engineering goal of the Rocket 305 was certification for a maximum altitude of 31,000 ft (9,500 m). Extending the altitude in the STC was abandoned due to cost/benefit considerations versus the difficulties with demonstrating compliance with the FAA requirements, plus changes to the supplemental oxygen systems in this non-pressurized aircraft. The aircraft will however climb at nearly 1,000 feet/minute above 24,000 (7,300 m). The Rocket conversion was discontinued by Rocket Engineering. The production version Mooney Acclaim now delivers faster speeds. As Rockets are available in the used market for about one-third the cost of a new Acclaim, it maintains its popularity among a small market niche.
Screamin' Eagle
Midwest M20 Sales & Service created the "Screamin' Eagle" using the long-body M20R Ovation 1 and Ovation 2 and M20S Eagle. The STC increases the maximum propeller RPM from 2500 to 2700 with the installation of a new propeller governor. This change allows the existing engine to produce 310 hp instead of 280 hp at full power. The STC also specifies a Hartzell 3-bladed metal or composite
scimitar propellerA scimitar propeller is shaped like a scimitar sword, with increasing sweep along the leading edge. Typically scimitar propellers are constructed of lightweight or composite materials. In the early 1900s they were made of laminated wood...
and increases the gross weight to 3374 lb (1,530.4 kg) on certain older models.
This STC is now licensed to Mooney Aircraft Company and sold as the Ovation 3.
Aircraft on display
The Mooney Super M20E is the aircraft most closely associated with
Robin MillerRobin Elizabeth Miller , known as "The Sugarbird Lady", was an Australian aviatrix and nurse. The name "The Sugarbird Lady" was given to her by outback Aboriginal children during her work combatting polio...
, an Australian female pilot known as the "Sugar Bird Lady" for her work in distributing the
polio vaccineTwo polio vaccines are used throughout the world to combat poliomyelitis . The first was developed by Jonas Salk and first tested in 1952. Announced to the world by Salk on April 12, 1955, it consists of an injected dose of inactivated poliovirus. An oral vaccine was developed by Albert Sabin...
across Australia. Her aircraft is preserved at
Jandakot AirportJandakot Airport is an Australian general aviation airport located in Jandakot, Western Australia. Jandakot airport opened in 1963. From 1 July 1998, Jandakot Airport Holdings purchased a 50-year lease with a 49-year option to operate and maintain the airport including its conservation...
near Perth, Australia.
Specifications (2007 Mooney M20TN Acclaim)
See also
External links