Schweizer SGM 2-37
Encyclopedia
The Schweizer SGM 2-37 is a two-place, side-by-side, fixed gear, low wing motor glider
.
A total of twelve were produced between 1982 and 1988, including nine for the United States Air Force Academy
, which designated it the TG-7A. The TG-7A was retired from USAFA service in April 2003.
The basic airframe was later developed into the SA 2-37A and B covert surveillance aircraft.
, but no examples were built. A single motorglider prototype, the Schweizer 2-31 was completed, but no further motorgliders were built by the company until 1982.
The SGM 2-37 was designed at the request of the USAF for use at USAFA, in both the powered and glider trainer role.
To save both money and development time the aircraft used a number of existing aircraft components:
The design was intended to be available as a civil aircraft as well as a military aircraft. The USAF version was delivered with a Lycoming O-235-L2C
4 cylinder aircraft engine of 112 hp. The civil version offered the same engine or an option of a Lycoming O-320
of 150 hp or a Lycoming O-360 of 180 hp.
The aircraft is of all metal aluminum monocoque
construction. The engine cowling is made from fiberglass
and plastics are employed in some of the nonstructural components.
The 2-37 features a 27 cu ft (764.6 l) baggage compartment behind the side-by-side seating. The aircraft does not have flaps, but instead has top-and-bottom wing-mounted balanced divebrakes, similar to other Schweizer glider designs.
Performance includes a cruise speed of 114 mph while burning 4 US gal per hour with the O-235 engine. The 17.9 aspect ratio wing provides a glide ratio of 29:1 and a minimum sink speed of 3.16 feet/sec (0.96 m/s). The SGS 2-37 was marketed by the company as being suitable for the following roles:
The 2-37 was later developed into the SA 3-38, known in military service as the RU-38 Twin Condor
.
under type certificate G1NE on March 22, 1983. The 2-37 type certificate is currently held by K & L Soaring of Cayuta, New York
. K & L Soaring now provides all parts and support for the Schweizer line of sailplanes.
, described the SGM 2-37 as: "Very versatile, very promising, very expensive". The publication's review noted that the USD
$70,000 base price did not include a feathering propeller, gyro instruments, wheel fairings, long range fuel tanks or other optional extras.
and designer Leslie E. Schweizer.
SGM 2-37
SA 2-37A
SA 2-37B
TG-7A
RG-8A
Motor glider
A motor glider is a fixed-wing aircraft that can be flown with or without engine power. The FAI Gliding Commission Sporting Code definition is: A fixed wing aerodyne equipped with a means of propulsion ,...
.
A total of twelve were produced between 1982 and 1988, including nine for the United States Air Force Academy
United States Air Force Academy
The United States Air Force Academy is an accredited college for the undergraduate education of officer candidates for the United States Air Force. Its campus is located immediately north of Colorado Springs in El Paso County, Colorado, United States...
, which designated it the TG-7A. The TG-7A was retired from USAFA service in April 2003.
The basic airframe was later developed into the SA 2-37A and B covert surveillance aircraft.
Development
Schweizer had flown a Schweizer SGU 1-19 as a motor glider in 1946 without putting the design into production. Later the company carried out a design study of a motorglider designated as the Schweizer 1-30Schweizer SGS 1-29
|-See also:-External links:*...
, but no examples were built. A single motorglider prototype, the Schweizer 2-31 was completed, but no further motorgliders were built by the company until 1982.
The SGM 2-37 was designed at the request of the USAF for use at USAFA, in both the powered and glider trainer role.
To save both money and development time the aircraft used a number of existing aircraft components:
- Nose, cowling and engine installation adapted from the Piper PA-38 TomahawkPiper PA-38 Tomahawk|-References:*Taylor, John W.R. Jane's All The World's Aircraft 1982-83. London:Jane's Yearbooks, 1982. ISBN 0-7106-0748-2.-External links:**-Related content:Comparable aircraft:* Aerotec Tangará* Alpha 2000 * Beechcraft Skipper...
- Wings adapted from the Schweizer SGS 1-36 SpriteSchweizer SGS 1-36 SpriteThe Schweizer SGS 1-36 Sprite is a United States, single-seat, mid-wing glider built by Schweizer Aircraft of Elmira, New York.The 1-36 was first flown in 1979 and a total of 43 were built by the time production was completed in 1982...
, including extensions to bring it from the Sprite's 46.2 feet (14.1 m) to 59.5 feet (18.1 m) and leading edge cuffLeading edge cuffLeading edge cuffs are a fixed aerodynamic device employed on fixed-wing aircraft to modify the airfoil used. They may be either factory-installed or, more commonly, an after-market modification....
s to improve stall characteristics - Tail from the Schweizer SGS 2-32Schweizer SGS 2-32The Schweizer SGS 2-32 is an American two-seat, mid-wing, two or three-place glider built by Schweizer Aircraft of Elmira, New York.The 2-32 was designed to be the highest performance two-place glider available, when it first flew in 1962. The 2-32 has been used as a tourist glider, trainer,...
The design was intended to be available as a civil aircraft as well as a military aircraft. The USAF version was delivered with a Lycoming O-235-L2C
Lycoming O-235
The Lycoming O-235 is a family of four-cylinder, air-cooled, horizontally opposed piston aircraft engines that produce , derived from the earlier O-233 engine....
4 cylinder aircraft engine of 112 hp. The civil version offered the same engine or an option of a Lycoming O-320
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...
of 150 hp or a Lycoming O-360 of 180 hp.
The aircraft is of all metal aluminum monocoque
Monocoque
Monocoque is a construction technique that supports structural load by using an object's external skin, as opposed to using an internal frame or truss that is then covered with a non-load-bearing skin or coachwork...
construction. The engine cowling is made from fiberglass
Fiberglass
Glass fiber is a material consisting of numerous extremely fine fibers of glass.Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the invention of finer machine tooling...
and plastics are employed in some of the nonstructural components.
The 2-37 features a 27 cu ft (764.6 l) baggage compartment behind the side-by-side seating. The aircraft does not have flaps, but instead has top-and-bottom wing-mounted balanced divebrakes, similar to other Schweizer glider designs.
Performance includes a cruise speed of 114 mph while burning 4 US gal per hour with the O-235 engine. The 17.9 aspect ratio wing provides a glide ratio of 29:1 and a minimum sink speed of 3.16 feet/sec (0.96 m/s). The SGS 2-37 was marketed by the company as being suitable for the following roles:
- Sailplane trainer
- Powered aircraft trainer
- Glider towplane (with larger horsepower engine option)
- Private touring aircraft
- Surveillance
- Aerial Inspection
The 2-37 was later developed into the SA 3-38, known in military service as the RU-38 Twin Condor
RU-38 Twin Condor
The Schweizer RU-38 Twin Condor is a two or three-seat, fixed gear, low wing, twin boom covert reconnaissance aircraft.RU-38 is the US military designation for the aircraft, indicating Utility, Reconnaissance...
.
Certification
The SGM 2-37 was certified by the Federal Aviation AdministrationFederal Aviation Administration
The Federal Aviation Administration is the national aviation authority of the United States. An agency of the United States Department of Transportation, it has authority to regulate and oversee all aspects of civil aviation in the U.S...
under type certificate G1NE on March 22, 1983. The 2-37 type certificate is currently held by K & L Soaring of Cayuta, New York
Cayuta, New York
Cayuta is a town in Schuyler County, New York, United States. The population was 545 at the 2000 census.The Town of Cayuta occupies the southeast corner of the county and is northeast of Elmira, New York.- History :...
. K & L Soaring now provides all parts and support for the Schweizer line of sailplanes.
Reception
Soaring, the journal of the Soaring Society of AmericaSoaring Society of America
The Soaring Society of America was founded at the instigation of Warren E. Eaton to promote the sport of soaring in the USA and internationally. The first meeting was held in New York City in the McGraw-Hill building on February 20, 1932. Its first objective was to hold a national soaring...
, described the SGM 2-37 as: "Very versatile, very promising, very expensive". The publication's review noted that the USD
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....
$70,000 base price did not include a feathering propeller, gyro instruments, wheel fairings, long range fuel tanks or other optional extras.
Operational history
There were nine aircraft still registered in the USA in April 2008. Current owners include the Tuskegee Airmen National Historical MuseumTuskegee Airmen
The Tuskegee Airmen is the popular name of a group of African American pilots who fought in World War II. Formally, they were the 332nd Fighter Group and the 477th Bombardment Group of the U.S. Army Air Corps....
and designer Leslie E. Schweizer.
Variants
- Motor glider for USAF and civil use, 12 completed.
SA 2-37A
- The SA 2-37A is a two seat special mission surveillance aircraft built for the Central Intelligence AgencyCentral Intelligence AgencyThe Central Intelligence Agency is a civilian intelligence agency of the United States government. It is an executive agency and reports directly to the Director of National Intelligence, responsible for providing national security intelligence assessment to senior United States policymakers...
and US Army and equipped with a Lycoming O-540-BLycoming O-540|-Specifications :-See also:-External links:...
powerplant of 235hp (175kW) and first flown in 1982 and eight. The US aircraft register records six SA-2-37As, including four belonging to Vantage Aircraft Leasing with serial numbers as high as 8. All are in the experimentalExperimental aircraftAn 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....
exhibition category.
SA 2-37B
- The SA 2-37B is a development of the 2-37A equipped with a Lycoming TIO-540-AB1ADLycoming O-540|-Specifications :-See also:-External links:...
powerplant of 250 hp. The aircraft is optimized for covert surveillance missions and carries FLIR and electronic sensors. It has a 500 pound (231 kg) sensor payload in a 70 cubic feet (1,982.2 l) fuselage bay. With a fuel capacity of 99 gallons (374.8 l) it can remain on station for up to 12 hours. Gross weight is 4300 lbs (1950 kg). The US aircraft registry records four SA 2-37Bs, all owned by Schweizer Aircraft. All are in the experimentalExperimental aircraftAn 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....
Research and Development category.
TG-7A
- United States Air Force designation for the SGM 2-37.
RG-8A
- In US Coast Guard service the SA 2-37 is designated RG-8A, indicating Glider, Reconnaissance.
Operators
- United States Air ForceUnited States Air ForceThe United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
- United States Coast GuardUnited States Coast GuardThe United States Coast Guard is a branch of the United States Armed Forces and one of the seven U.S. uniformed services. The Coast Guard is a maritime, military, multi-mission service unique among the military branches for having a maritime law enforcement mission and a federal regulatory agency...
- Colombian Air ForceColombian Air ForceThe Colombian Air Force or FAC is the Air Force of the Republic of Colombia.The Colombian Air Force is one of the three institutions of the Armed Forces of Colombia, charge according to the 1991 Constitution of the work to exercise and maintain control of Colombia's airspace to defend the...
- Mexican Air ForceMexican Air ForceThe Mexican Air Force is the aviation branch of the Mexican Army and depends on the National Defense Secretariat . Since 2008, its commander is Gen...