The PA-20 Pacer and PA-22 Tri-Pacer are a family of four-place, strut braced, high-wing light aircraft that were built by Piper Aircraft in the post-World War II period. The Pacer was essentially a four-place version of the two-place PA-17 Vagabond light aircraft. It features a steel tube fuselage and an aluminum frame wing, covered with fabric, much like Piper's most famous aircraft, the Cub and Super Cub. An aircraft prized for its ruggedness, spacious cabin, and, for its time, impressive speed, many Pacers continue to fly today. Factory installed 125 hp, 135 hp, 150 hp, and 160 hp engine options were available, and 180 hp engine after-market conversions are an option.
Development
The Piper PA-20 Pacer was originally designed as a tailwheel aircraft and thus had somewhat limited forward visibility on the ground and more demanding ground-handling characteristics. To help introduce more pilots to easier, safer flying, from February 1951, Piper introduced the PA-22 Tri-Pacer with a nosewheel instead of the tailwheel landing gear. Both the Pacer and the Tri-Pacer belong to a sub-group of Piper aircraft called "Short Wing Pipers." Additionally, the Tri-Pacer offered higher-powered engine options in the form of 150 hp and 160 HP engines, whereas the largest engine available to the original Pacer had an output of 135 hp. At the time the tricycle undercarriage became a popular preference and 1953 saw the PA-22 Tri-Pacer outsell the Pacer by a ratio of six to one. Due to the geometry of the nosewheel installation it is sometimes called the "Flying Milk Stool". In 1959 and 1960 Piper offered a cheaper, less well-equipped version of the Tri-Pacer with a 150 HP Lycoming O-320 designated the PA-22-150 Caribbean. Over 9400 Tri-Pacers were produced between 1950 and 1964 when production ended, with 3280 still registered with the FAA in April 2018. An unusual feature of the Tri-Pacer is the incorporation of bungee-linked ailerons and rudder. Beside simplifying the coordination of inflight manoeuvres, this system which can easily be overcome by the pilot as required, allowed the installation of a simplified form of autopilot marketed by Piper under the name Auto-control. A small number of PA-22s have been converted to taildragger configuration, resulting in an aircraft that is very similar to a PA-20 Pacer, but which retains the model refinements and features of the PA-22. These conversions are often referred to by owners as PA-22/20s and are often listed in classified aircraft ads as such, although officially such converted aircraft continue to be designated by the FAA as PA-22 Tri-Pacers. When this conversion is accomplished, a 2 puck disc brake conversion is usually installed in place of the original drum brakes, and the Lycoming O-360 180 HP engine is the preferred upgrade. Some PA-22s have a Hartzell constant-speed controllable propeller or Koppers Aeromatic propeller. Each of these installations improves performance/economy at the sacrifice of payload. A trainer version of the PA-22 Tri-Pacer was designed and designated the PA-22-108 Colt. It was intended to compete directly with other popular trainers of the day, such as the Cessna 150 and was powered by a 108 hp Lycoming O-235. Over 2,000 Colts were manufactured during the two production years. The Colt closely resembles the Tri-Pacer and uses the same landing gear, engine mounts, seats, windshield, door, tail surfaces, struts and the same instrument panel as well. A few Colts have also been converted to tailwheel configuration, although this is not as popular as converting Tri-Pacers. The last batch of 12 PA-22-150s were built for the French Army in 1963 and the last of the family a PA-22-108 Colt was completed on 26 March 1964. The type was replaced on the Vero Beachproduction line by the PA-28 Cherokee 140.
Operational history
Cuba
Between 1953 and 1955, the Cuban Army Air Force received 7 PA-20s, 4 PA-22-150s, and 3 PA-22-160s. During the Cuban Revolution, PA-22s had their rear-doors removed and a.30 caliber machine gun installed in its place for use against insurgents, along with hand-dropped grenades. A PA-22 providing ground support for the Cuban Army during the Battle of Guisa is believed to be the lone aircraft lost by the FAEC to enemy fire.
Katanga
During the Congo Crisis, Katangese separatists received five PA-22-150s from the South African Air Force for the Force aérienne katangaise. Deployed against ONUC forces between 1961 and 1963, their status at the end of the conflict remained somewhat uncertain.
