Swiss SGM 2-37
| SGM 2-37 | |
|---|---|
|
|
| Type: | Motor sailer |
| Design country: | |
| Manufacturer: | |
| First flight: |
1982 |
| Commissioning: |
1982 |
| Production time: |
1982-1988 |
| Number of pieces: |
12 |
The Swiss SGM 2-37 is a two-seater motor glider with a rigid landing gear . The low-wing aircraft was developed by the US manufacturer Schweizer Aircraft Corporation . A total of twelve copies were built between 1982 and 1988 - nine of them for the United States Air Force Academy , which provided the aircraft with the designation TG-7A . In April 2003 the TG-7A was taken out of service. Based on the SGM 2-37, the reconnaissance aircraft SA 2-37A and SA 2-37B were later developed.
history
Already in 1946, the Swiss had tried from their glider 1-19 SGU to develop a motor glider. However, as the test flights were unsuccessful and the aircraft was unable to climb above 10 ft (3 m) on its own due to the weak engine, the project was discontinued. In 1958, the company and the Swiss SA 1-30 developed a prototype of a motorized aircraft for which the wings and tail unit of the SGS 1-26 glider were used. This construction was not built in series either. In 1960, Schweizer developed the SA 2-31, a two-seater version of the SA 1-30, which, however, also did not find its way into series production due to competition in the light aircraft market . Both the SA 1-30 and the SA 2-31 were designed as powered aircraft and the company did not build any other powered gliders until 1982.
The Swiss RU-38 Twin Condor was later developed from the SGM 2-37 .
construction
The SGM 2-37 was developed on behalf of the USAFA as a training aircraft for powered flight and glider flight alike. To save time and money on development, various components from other aircraft were used:
- The nose, cowling and engine of the Piper PA-38
- The wings of the Swiss SGS 1-36 Sprite , extended from 46.2 ft (14.1 m ) to 59.5 ft (18 m), with slats to improve slow flight characteristics
- Tail unit of the Swiss SGS 2-32
The construction should be usable in both civil and military areas. The military version for the US Air Force was equipped with a Lycoming O-235 -L2C four-cylinder engine with a rated output of 112 hp (82 kW ). The civil version was equipped with the same engine or optionally with a Lycoming O-320 with 150 PS (110 kW) or a Lycoming O-360 with 180 PS (132 kW).
The hull consists of a monocoque made of aluminum . The wings are also made of aluminum. The cowling is made of GRP . The SGM 2-37 has a luggage compartment with a size of 760 liters behind the adjacent seats. Like Schweizer's gliders, the SGM 2-37 is not equipped with landing flaps , but with airbrakes above and below the wing.
With the O-235 engine, the machine reaches a cruising speed of 99 kn (183 km / h ) with a fuel consumption of 15 liters per hour. With a stretching of the wings of the aircraft has 17.9 with folded propeller via a slip ratio of 28: 1 and a minimum sink rate of 3.16 ft / s (0.96 m / s).
The SGS 2-37 was offered for the following areas of application:
- Training aircraft for gliding
- Training aircraft for powered flight
- Tow aircraft for gliders (with more powerful engine)
- Private touring plane
- Reconnaissance plane
- Air surveillance aircraft
The SGM 2-37 received its type certification from the Federal Aviation Administration on March 22, 1983. The certification is currently running for the company K & L Soaring from Cayuta , New York . K & L Soaring offers spare parts and customer service for all Schweizer gliders.
use
From 1985 the US Army used the TG-7 for covert reconnaissance missions as part of the “Grisly Hunter” project. Thereafter, the two aircraft were moved to the US Coast Guard in mid-1989 , where they were rebuilt and given the designation RG-8A. They were painted gray for camouflage and used for coastal patrols. They were stationed at the Opa-locka Executive Airport in Miami .
Versions
- SGM 2-37
- Motor glider for the US Air Force and civilian use, twelve built
- SA 2-37A
- The SA 2-37A is a two-seat reconnaissance aircraft that was built for the Central Intelligence Agency and the US Army and is powered by a Lycoming O-540 -B with 235 PS (173 kW ). The first flight took place in 1982.
- SA 2-37B
- The SA 2-37B is a further development of the 2-37A. It is powered by a Lycoming TIO-540-AB1AD with 250 PS (184 kW). The aircraft is optimized for secret reconnaissance missions and equipped with FLIR and other sensors. With a tank volume of 370 liters, the machine can be in the air for up to twelve hours. The total weight is 1950 kg.
- TG-7A
- Name of the US Air Force for the SGM 2–37
- RG-8A
- Designation of the US Coast Guard for SA 2-37
operator
Incidents
On February 19, 1998, the machine with the registration number N61474 took off from the airfield in Green Cove Springs , Florida . At an altitude of two to three hundred feet AGL the engine lost power for unknown reasons and the pilot attempted to return to the field for an emergency landing . During a steep left turn it stalled and the aircraft hit an empty houseboat . Both occupants were killed in the accident and the aircraft was destroyed.
Technical data (SGM 2–37)
| Parameter | Data |
|---|---|
| crew | 2 |
| length | 27.5 ft (8.4 m ) |
| span | 59.5 ft (18.1 m) |
| height | 7.7 ft (2.3 m) |
| Wing area | 195.7 ft² (18.2 m² ) |
| payload | 650 lb (295 kg ) |
| Empty mass | 1,200 lb (544 kg) |
| Max. Takeoff mass | 1,850 lb (839 kg) |
| Cruising speed | 112 mph (180 km / h ) |
| Top speed | 135 mph (217 km / h) |
| Service ceiling | 14,000 ft (4,267 m) |
| Range | 230 mi (370 km ) |
| Engine | Lycoming O-235 -L2C |
See also
Web links
Individual evidence
- ↑ a b c d e SGS 2–37 Swiss. Activate Media, archived from the original ; accessed on March 6, 2020 (English).
- ↑ a b c d e f g Bob Said: 1983 Sailplane Directory . In: Soaring Magazine . Soaring Society of America, Nov 1983, pp. 131 (English).
- ↑ a b c d e f TG-7A. United States Air Force Academy , archived from the original ; accessed on March 6, 2020 (English).
- ^ A b Reconnaissance Aircraft: SA 2-37B. Swiss Aircraft Corporation , 2006, archived from the original ; accessed on March 5, 2020 (English).
- ^ A b Paul A. Schweizer: Wings Like Eagles, The Story of Soaring in the United States . 2nd Edition. Smithsonian Institution Press, 1988, ISBN 978-0-87474-827-7 , pp. 120 (English).
- ^ Paul A. Schweizer: Sailplanes by Schweizer: A History . Airlife, The Crowood Press Ltd 1998, ISBN 978-1-84037-022-5 (English).
- ^ Directory of Airplanes. Smithsonian National Air and Space Museum , accessed March 6, 2020 .
- ^ Swiss 2–31 profiles. aircraftprofile.com, accessed on March 6, 2020 .
- ↑ Model (TCDS) information. Federal Aviation Administration , accessed March 6, 2020 .
- ↑ K & L Soaring website. K&L Soaring, LLC, accessed March 6, 2020 .
- ^ Frederick Thomas Jane, Paul Jackson: Jane's All the World's Aircraft . Jane's Information Group, 2007, pp. 874 (English).
- ↑ Swiss SA 2-37 with Colombian national emblem. Retrieved March 6, 2020 .
- ^ Sergio Echeverria Garcia: Swiss SA2-37A Condor - Mexico - Air Force. Airliners.net, June 21, 2005, accessed March 6, 2020 .
- ^ National Transportation Safety Board - Aviation Accident Final Report. Federal Aviation Administration , February 15, 2001, accessed March 7, 2020 .
