Cessna 336 Skymaster
337 Super Skymaster
Cessna 337 Skymaster
Role Personal use and air taxi aircraft
National origin United States
Manufacturer Cessna
Reims Aviation
First flight February 28, 1961
Introduction 1962
Produced 1963–1982
Number built 2,993[1]
Variants Cessna O-2 Skymaster
Conroy Stolifter
Spectrum SA-550

The Cessna Skymaster is an American twin-engine civil utility aircraft built in a push-pull configuration. Its engines are mounted in the nose and rear of its pod-style fuselage. Twin booms extend aft of the wings to the vertical stabilizers, with the rear engine between them. The horizontal stabilizer is aft of the pusher propeller, mounted between and connecting the two booms.[1] The combined tractor and pusher engines produce centerline thrust and a unique sound.[2] The Cessna O-2 Skymaster is a military version of the Cessna 337 Super Skymaster.

Development

Retracting landing gear

The first Skymaster, Model 336 Skymaster, had fixed landing gear and initially flew on February 28, 1961.[3][4] It went into production in May 1963[1] with 195 being produced through mid-1964.[2]

In February 1965, Cessna introduced the Model 337 Super Skymaster.[5] The model was larger, and had more powerful engines, retractable landing gear, and a dorsal air scoop for the rear engine. (The "Super" prefix was subsequently dropped from the name.)[2] In 1966, the turbocharged T337 was introduced, and in 1973, the pressurized P337G entered production.[2]

Cessna built 2993 Skymasters of all variants, including 513 military O-2 versions.[1] Production in America ended in 1982, but was continued by Reims in France, with the FTB337 STOL and the military FTMA Milirole.[4]

Design

Fuselage close-up with door open
Flight deck

The Skymaster handles differently from a conventional twin-engine aircraft, primarily in that if an engine fails, the plane will not yaw toward that engine. Without the issue of differential thrust inherent to conventional (engine-on-wing) twins, engine failure on takeoff will not produce yaw from the runway heading. With no one-engine-out minimum controllable speed (Vmc), in-flight control at any flying speed with an engine inoperative is not as critical as it is with engines on the wing with the associated leverage; however, performance in speed and, particularly, rate of climb are affected. Flying a Skymaster requires a pilot to hold a multiengine rating, although many countries issue a special "centerline thrust rating" for the Skymaster and other similarly configured aircraft.[2]

Ground handling requires certain attention and procedures. The rear engine tends to overheat and can quit while taxiing on very hot days.[6] Accidents have occurred when the runway is shorter than the single-engine take-off roll and pilots, unaware of a rear engine shutdown, have attempted take-off on the nose engine alone.[7] Federal Aviation Administration Airworthiness Directive 77-08-05 prohibits single-engine take-offs and requires the installation of a placard marked "DO NOT INITIATE SINGLE ENGINE TAKEOFF".[8]

The Skymaster's unique sound is made by its rear pusher propeller slicing through turbulent air from the front propeller and over the airframe while its front tractor propeller addresses undisturbed air.[2]

Operational history

From 1976 until the middle 1990s, the California Department of Forestry and Fire Protection used O-2 variants of the 337 Skymaster as tactical aircraft during firefighting operations. These were replaced with North American OV-10 Broncos, starting in 1993.[9]

During the Rhodesian Bush War, the Reims-Cessna FTB 337G 'Lynx' was the main light attack aircraft used by Rhodesian Security Forces during Fire Force counterinsurgency air assault missions, which began in 1974. The Lynxes were armed with twin Browning .303 machine guns mounted above the wing and 37mm SNEB rockets, locally made Mini "Alpha" Bombs (cluster bombs), Mini "Golf" Bombs (450 lb (200 kg) blast and shrapnel bomb) and Frantan (a napalm variant carried in frangible drop tanks) bombs.[10]

Brothers to the Rescue

Main article: Brothers to the Rescue

From 1991 until 2001 the Cuban exile group Hermanos al Rescate (Brothers to the Rescue) used Skymasters, among other aircraft, to fly search and rescue missions over the Florida Straits looking for rafters attempting to cross the straits to defect from Cuba, and when they found them, dropped life-saving supplies to them. Rescues were coordinated with the US Coast Guard, which worked closely with the group. They chose Skymasters because their high wing offered better visibility of the waters below, they were reliable and easy to fly for long-duration missions (averaging 7 hours), and they added a margin of safety with twin-engine centerline thrust. In 1996, two of the Brothers to the Rescue Skymasters were shot down by the Cuban Air Force over international waters. Both aircraft were downed by a MiG-29, while a second jet fighter, a MiG-23, orbited nearby.[11]

Variants

Cessna

USAF O-2A over Panama

Reims Cessna

Reims F337G Skymaster

Conversions/modifications

Military operators

Thai Navy T337H-SP
 Angola
FAPA/DAA[17]
 Burkina Faso
Force Aérienne du Burkina Faso[18]
 Colombia
Colombian Air Force[19]
 Mozambique
Força Aérea de Moçambique (3 x FTB-337G) - ex-Portuguese Air Force FTB-337G refurbished and offered by the Government of Portugal to Mozambique in 2011 and 2012.[20]
 Namibia
Namibian Air Force[citation needed]
 Nicaragua
Nicaraguan Air Force[21]
 Togo
Togo Air Force[3]
 Zimbabwe
Air Force of Zimbabwe[3]

Former military operators

 Argentina
Gendarmeria Nacional Argentina Two examples, 1965-1986[22]
 Bangladesh
Bangladesh Air Force[23]
 Chile
Chilean Army Three examples, between the end of 1970s and mid-1990s, sold to civilian interests.[citation needed]
 Chad
Chadian Air Force[3]
 Ecuador
Ecuadorian Air Force[3]
 El Salvador
Air Force of El Salvador[3]
 Equatorial Guinea
Armed Forces of Equatorial Guinea[24]
 Guinea-Bissau
Força Aérea de Guine-Bissau[25]
 Haiti
Haitian Air Force[3]
 Jamaica
Jamaica Defense Force[3]
 Niger
Military of Niger[21]
 Mexico
Mexican Air Force[3]
 Portugal
Portuguese Air Force[3] (32 × FTB-337G): Purchased in 1973 to replace the force's aging Dornier Do 27 fleet, which had been used intensively in the Portuguese Colonial War. The first 337 deliveries did not arrive until December 1974—after the end of the war. The last Skymaster in service with the Portuguese Air Force was retired on July 25, 2007.
 Rhodesia
Rhodesian Air Force[26]
 Senegal
Senegalese Air Force[27][unreliable source?]
 Sri Lanka
Sri Lanka Air Force[3]

Specifications (337D)

3-view line drawing of the Cessna T337C Turbo System Super Skymaster
3-view line drawing of the Cessna T337C Turbo System Super Skymaster

Data from Jane's All The World's Aircraft 1969–70[28]

General characteristics

Performance

See also

Related development

Aircraft of comparable role, configuration, and era

References

  1. ^ a b c d Wood, Derek: Jane's World Aircraft Recognition Handbook, page 471. Jane's Publishing Company, 1985. ISBN 0-7106-0343-6
  2. ^ a b c d e f Plane and Pilot: 1978 Aircraft Directory, page 92. Werner & Werner Corp Publishing, 1978. ISBN 0-918312-00-0
  3. ^ a b c d e f g h i j k l m Taylor, Michael: Encyclopedia of Modern Military Aircraft; page 67; Gallery Books; 1987; ISBN 0-8317-2808-6
  4. ^ a b c d e f Fitzsimons, Bernie: The Defenders - A Comprehensive Guide to the Warplanes of the USA, page 54. Gallery Books, 1988. ISBN 0-8317-2181-2
  5. ^ Green, William: Observers Aircraft, page 46. Frederick Warne Publishing, 1974. ISBN 0-7232-1526-X
  6. ^ McClellan, J Mac: Adam A500, Flying Magazine pages 52-58. Hachette Filipacchi Media U.S., December 2007. ISSN 0015-4806
  7. ^ "NTSB Identification: CEN12FA058, 14 CFR Part 91: General Aviation". NTSB. November 10, 2011.
  8. ^ "Airworthiness Directive 77-08-05". Federal Aviation Administration. April 28, 1977. Retrieved October 24, 2014.
  9. ^ "CDF aviation management history". State of California. Retrieved July 4, 2015.
  10. ^ Cocks, Chris (2009). Fireforce: One Man's War in the Rhodesian Light Infantry. 30° South Publishers. p. 33. ISBN 978-0-9584890-9-6.
  11. ^ University of Minnesota Human Rights Library (1999). "Armando Alejandre Jr., Carlos Costa, Mario de la Pena y Pablo Morales v. Republica de Cuba, Case 11.589, Report No. 86/99, OEA/Ser.L/V/II.106 Doc. 3 rev. at 586 (1999)". Retrieved December 7, 2007.
  12. ^ Murphy, Daryl (2006). "The Cessnas that got away". Archived from the original on February 27, 2009. Retrieved December 22, 2008.
  13. ^ a b Taylor 1969, pp. 304–305.
  14. ^ Mitzar, Flying Pinto? Archived August 16, 2004, at the Wayback Machine
  15. ^ The Spectrum SA-550 Archived 2009-03-14 at the Wayback Machine
  16. ^ Graham Warwick (October 25, 2018). "E-Fan Experience Spawns French Hybrid-Electric Startup". Aviation Week & Space Technology.
  17. ^ Fontanellaz, Cooper & Matos 2020, p. 13
  18. ^ Flight International 16–22 November 2004, p. 47.
  19. ^ Flight International 16–22 November 2004, p. 52.
  20. ^ Mais Alto June 2012, p. 16.
  21. ^ a b Flight International 16–22 November 2004, p. 77.
  22. ^ Aeroflight website
  23. ^ Flight International 16–22 November 2004, p. 45.
  24. ^ Flight International 16–22 November 2004, p. 56.
  25. ^ Flight International 16–22 November 2004, p. 62.
  26. ^ Brent, W A (1988). Rhodesian Air Force – A Brief History 1947–1980. Freeworld. pp. 13–23. ISBN 0620118059.
  27. ^ World Air Forces – Countries "World Air Forces Countries". Archived from the original on July 16, 2012. Retrieved February 15, 2021..
  28. ^ Taylor 1969, pp. 303–304.