Mooney M20
The Mooney M20 is a family of piston-powered, four-seat, propeller-driven, general aviation aircraft, all featuring low wings and tricycle gear, manufactured by the Mooney International Corporation.
The M20 was the 20th design from Al Mooney, and his most successful. The series has been produced in many variations over the last 60 years, from the wooden-wing M20 and M20A models of 1955, to the M20V Acclaim Ultra that debuted in 2016. More than 11,000 aircraft in total have been produced across three production runs, the most recent concluding in 2019.
In November 2008, Mooney International announced that it was halting all production as a result of the late-2000s recession, but would still provide parts and support for the existing fleet. With the injection of new capital from the company's purchase by a Chinese private equity firm, production of the M20 resumed in February 2014. Since then, the company has released two more M20 models.
Development
Al Mooney had been developing preliminary designs for the four-seater M20 for some time, while the single-seat M-18 Mite was in production in the late 1940s and early 1950s. When in early 1953 the company moved from Wichita, Kansas, to Kerrville, Texas, and when it became clear that the Mite was nearing the end of its production, development of the M20 accelerated. The first M20 flight took place on September 3, 1953, and it was certified on August 24, 1955.During 1955, the company sold 10 of the M20 airplanes. Due to start-up costs, they lost about $3000 on each airplane. In 1956, they delivered 51 airplanes, and in 1957 the total was 105. The airplane gained attention because it was able to achieve speeds up to with a Lycoming O-320 engine. The combination of speed and efficiency was noteworthy. In 1958 the M20A joined the lineup with a larger Lycoming O-360-A1A engine, and by 1959, this was the only model offered, 231 units were sold that year. 1959 was also the first year that the company made a profit. The M20A continued production into 1960, when 166 were delivered. These were the last of the Mooneys to have wooden structures in the wings and tail. Early in the model's history, several incidents of wooden tails breaking up in flight occurred 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 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.
1960s
In January 1960, the Mooney company convinced Ralph Harmon to leave McDonnell Aircraft in St. Louis, Missouri, and take over management of the engineering efforts. He insisted on replacing the wood in the M20 with aluminum, and the all-metal M20B was completed by the end of 1960, less than a year after his arrival. In 1961, the company sold 222 M20B airplanes. The following year, the M20C was introduced and 336 were sold that year. Also known as the Mark 21 and later the Ranger, the M20C had several improvements over the M20B, including greater deflection on control surfaces, reduced cowl flap openings for better engine cooling, improved exhaust scavenging with a Hanlon and Wilson exhaust system, new battery access door, more powerful landing light, lightweight floor, an increased gross weight of, lighter empty weight, new instrument panel layout, and a higher maximum flap angle of 33 degrees.In 1963, the M20D was introduced, essentially an M20C with fixed landing gear and a fixed-pitch propeller. This had a slightly lower price than the M20C and was intended as a basic or trainer model which would have lower insurance costs and which would compete with the Piper Cherokee 180. It could be upgraded with retractable landing gear, and in fact, most of them were upgraded over the years. The M20D was produced from 1963 to 1966 with a total production of 161 units. In 1964 the M20E Super 21 was introduced. It was also based on the M20C but with a more powerful Lycoming fuel-injected engine. The company sold 366 M20E units that year.
In 1965, a new feature was introduced to the M20. It was called "positive control" and was a single-axis autopilot produced by Brittain Industries. It maintained the wings of the airplane in a level position unless a button on the control wheel was depressed for turns and banks. It was a controversial feature, liked by some pilots and disliked by others. Production and sales of the M20 continued to increase. In 1966, a total of 760 units were delivered, including 280 of the M20C Mark 21 planes and 473 of the M20E Super 21s. A new model, the M20F Executive 21, offered more legroom due to a increase in cabin length which also allowed for a third fuselage side window. It had of fuel capacity compared to in earlier models, and grossed an additional. This year, the company exceeded $1,000,000 in profits.
The M20G Statesman, a version of the M20F with less-powerful engine, was released in 1968. It had a larger airframe than the M20C, but the same engine, and as a result was slower. It was not as successful as the M20F and was produced for only three years, from 1968 to 1970, with a total production run of 189 units.
Despite strong sales, Mooney was short of cash. The company went into chapter 7 bankruptcy in early 1969, and was acquired by American Electronics Laboratories and then Butler Aviation International. Sales that year were less than half of the previous year's figures, although a new version of the M20E Chaparral was released with electrically operated flaps and landing gear. Butler Aviation also acquired the troubled Aerostar company and combined it with Mooney in an attempt to save both. The Mooney name was dropped in 1970, as was the M20 designation; the planes were called Aerostars.
1970s
Butler Aviation closed the Mooney plant in early 1971, and it remained closed for more than two years. In October 1973, Mooney was purchased by Republic Steel. Robert Cumming, a general manager at Republic Steel, had owned a Mooney M20F Executive for years and flew it frequently, and wished to put the Mooney M20 back into production. This began in January 1974 with the reintroduction of the M20F Executive. Roy LoPresti, formerly of Grumman American, had been hired as the vice president of engineering. Through the efforts of his engineering group, various improvements were made to the M20 with the goal of increasing its speed, and the M20J was introduced in July 1976. It was also known as the Mooney 201 because it was capable of with its engine. The 201 was a big seller, and a turbocharged version was developed later that year. The next year, 1977, three models were offered: the M20C Ranger, the M20F Executive, and the M20J 201. By 1979, the M20C had been dropped, ending production of the short-body M20.The same year, 1979, the company's first turbocharged M20 was released: the M20K 231, so designated because its top speed was. It was based on the earlier 201 with further improvements. It had a wider wingspan and a six-cylinder Continental engine, and the fuel capacity was increased to. This year, a total of 439 airplanes were delivered—fewer than the top years of the 1960s, but these deliveries resulted in healthy profits. From this point through 1986, the M20J and the turbocharged M20K were the only two models offered.
1980s
General aviation manufacturing experienced a significant downturn starting in 1982. Mooney was affected along with other manufacturers and was forced to downsize through temporary layoffs. Despite the recession, development work continued. The 201 and 231 received more improvements, including significant reductions in cabin noise levels. In 1982, deliveries fell to 218 units, and in 1983 only 154 aircraft were produced. The United States Air Force announced a competition to develop a replacement for the Cessna T-41 trainer, and Mooney immediately began to develop a military trainer based on the 231.While the company was dealing with the recession, Republic Steel was acquired by the Ling-Temco-Vought corporation and dropped Mooney. The company ended up in the hands of Armand Rivard of Lake Aircraft and Alexandre Couvelair, a Mooney dealer from Paris. Sales continued to fall, totaling 143 in 1984 and 99 in 1985.
The next new model, the M20K 252, appeared in early 1986 with a top speed of. It replaced the 231 and achieved its higher speed with the same engine. It featured a new 28-volt electrical system to power additional equipment and to improve cold-weather starting. The Continental TSIO-360-GB engine in the 231 had required specific pilot training and modified takeoff and climb procedures to operate at acceptable engine temperatures in hot weather. Because of this, the 252 received an intercooled TSIO-360-MB engine. The various improvements were copied to the 201 airframe, and the new 205 model was released in 1987.
This was followed in 1988 by the M20L PFM, powered by a Porsche PFM 3200 engine which had been developed from the 911 Carrera engine. The maximum speed with this configuration was. The fuselage was stretched to form the first long-body M20. One new feature on this airplane was the replacement of the throttle, mixture and propeller controls with a single power control; mixture and propeller rotation speed were automatically adjusted based on the setting of this single control. The Mooney PFM did not last, a total of 41 units having been manufactured in 1988 and 1989. Most M20Ls no longer use this unique engine, as factory support ceased in 2005.
In February 1989, the next M20 model was released: the M20M TLS. It was powered, as the name hinted, by a turbocharged Lycoming six-cylinder engine that produced at 2,575 rpm, and it had a three-bladed propeller. It was capable of cruising at and had a range of and a maximum climb rate of per minute. The first year, the TLS accounted for 30 of the 143 aircraft delivered, and in 1990, this increased to 61 units. Also in 1989, Mooney released a trainer model based on the M20J. Beech, Cessna, and Piper had all stopped production of trainers throughout the 1980s, and the 201AT was designed to fill this gap. From 1989 to 1992, 20 units were delivered.