Cessna Skymaster
Encyclopedia
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
built in a push-pull configuration
Push-pull configuration
An aircraft constructed with a push-pull configuration has a mixture of forward-mounted propellers and backward-mounted propellers.-Historical:...
. Its engines are mounted in the nose and rear of its pod-style fuselage. Twin boom
Twin boom
Twin-boom aircraft have their tailplanes and vertical stabilizers mounted on the tail of either two fuselages or on two booms fixed to either both sides of the single fuselage, the wings or the engine nacelles.The reason for this design choice may be:...
s extend aft of the wings to the vertical stabilizer
Vertical stabilizer
The vertical stabilizers, vertical stabilisers, or fins, of aircraft, missiles or bombs are typically found on the aft end of the fuselage or body, and are intended to reduce aerodynamic side slip. It is analogical to a skeg on boats and ships.On aircraft, vertical stabilizers generally point upwards...
s, with the rear engine between them. The horizontal stabilizer
Tailplane
A tailplane, also known as horizontal stabilizer , is a small lifting surface located on the tail behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed wing aircraft such as helicopters and gyroplanes...
is aft of the pusher propeller, mounted between and connecting the two booms. The combined tractor
Tractor configuration
thumb|right|[[Evektor-Aerotechnik|Aerotechnik EV97A Eurostar]], a tractor configuration aircraft, being pulled into position by its pilot for refuelling....
and pusher
Pusher configuration
In a craft with a pusher configuration the propeller are mounted behind their respective engine. According to Bill Gunston, a "pusher propeller" is one mounted behind engine so that drive shaft is in compression...
engines produce 'centerline' thrust and a unique sound.
Development
The first Skymaster, model 336, had fixed landing gear and first flew on February 28, 1961. It went into production in May 1963, and 195 were produced through mid 1964.In February 1965 Cessna introduced the model 337 Super Skymaster. The model was larger, and had more powerful engines, retractable landing gear, and a dorsal air scoop for the rear engine ("Super" was subsequently dropped from the name). In 1966 the turbocharged T337 was introduced, and in 1973 the pressurized P337G entered production.
Cessna built 2993 Skymasters of all variants, including 513 military O-2
O-2 Skymaster
The O-2 Skymaster is a military version of the Cessna 337 Super Skymaster utilized as an observation and forward air control aircraft...
versions. Production in America ended in 1982 but continued with Reims
Reims Aviation
Reims Aviation Industries is a French aircraft manufacturer located in the city of Reims, currently producing the F406 Caravan II. Reims Aviation is a wholly owned subsidiary of GECI Aviation.-History:...
in France with the FTB337 STOL
STOL
STOL is an acronym for short take-off and landing, a term used to describe aircraft with very short runway requirements.-Definitions:There is no one accepted definition of STOL and many different definitions have been used by different authorities and nations at various times and for a myriad of...
and the military FTMA Milirole. Production totalled 94 units.
Design
The Skymaster handles differently from a conventional twin-engine aircraft, primarily in that it will not yawAircraft principal axes
An aircraft in flight is free to rotate in three dimensions: pitch, nose up or down about an axis running from wing to wing), yaw, nose left or right about an axis running up and down; and roll, rotation about an axis running from nose to tail. The axes are alternatively designated as lateral,...
into the dead engine if one engine fails. Without the issue of differential thrust inherent to conventional (engine-on-wing) twins, engine failure on takeoff will not produce yaw from the runway direction. 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. Nevertheless, the Skymaster requires a multi-engine-rating, although many countries issue a special "centerline thrust rating" for Skymaster and other like-configurated aircraft.
Ground handling requires certain attention and procedures. The rear engine tends to overheat and can quit while taxiing
Taxiing
Taxiing refers to the movement of an aircraft on the ground, under its own power, in contrast to towing or push-back where the aircraft is moved by a tug...
on very hot days. There have been accidents when pilots, unaware of the shutdown, have attempted take-off on the nose engine alone, even though the single-engine take-off roll exceeded the particular runway length. FAA
Federal 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...
Airworthiness Directive
Airworthiness Directive
An Airworthiness Directive is a notification to owners and operators of certified aircraft that a known safety deficiency with a particular model of aircraft, engine, avionics or other system exists and must be corrected....
77-08-05 prohibits single engine take-offs and requires the installation of a placard with words that say "DO NOT INITIATE SINGLE ENGINE TAKEOFF".
The Skymaster produces a unique sound: a combination sound of its rear propeller slicing through turbulent air from the front prop and over the airframe, while its nose propeller addresses undisturbed air.
Operational history
From 1976 until the middle 1990s, the California Department of Forestry and Fire ProtectionCalifornia Department of Forestry and Fire Protection
The California Department of Forestry and Fire Protection is the State of California's agency responsible for fire protection in State Responsibility Areas of California as well as the administration of the state's private and public forests. It is often referred to as The California Department of...
used O-2 variants of the 337 Skymaster as tactical aircraft during firefighting operations. These were replaced with North American OV-10 Bronco
OV-10 Bronco
The North American Aviation Rockwell OV-10 Bronco is a turboprop light attack and observation aircraft. It was developed in the 1960s as a special aircraft for counter-insurgency combat, and one of its primary missions was as a forward air control aircraft...
s, starting in 1993.
Brothers to the Rescue
From 1991 until 2001 the CubaCuba
The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...
n exile group Hermanos al Rescate (Brothers to the Rescue) used Skymasters, among other aircraft, to fly search and rescue
Search and rescue
Search and rescue is the search for and provision of aid to people who are in distress or imminent danger.The general field of search and rescue includes many specialty sub-fields, mostly based upon terrain considerations...
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, who 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 (FAC) over international waters. Both aircraft were downed by a MiG-29
Mikoyan MiG-29
The Mikoyan MiG-29 is a fourth-generation jet fighter aircraft designed in the Soviet Union for an air superiority role. Developed in the 1970s by the Mikoyan design bureau, it entered service with the Soviet Air Force in 1983, and remains in use by the Russian Air Force as well as in many other...
, while a second jet fighter, a MiG-23
Mikoyan-Gurevich MiG-23
The Mikoyan-Gurevich MiG-23 is a variable-geometry fighter aircraft, designed by the Mikoyan-Gurevich design bureau in the Soviet Union. It is considered to belong to the Soviet third generation jet fighter category, along with similarly aged Soviet fighters such as the MiG-25 "Foxbat"...
orbited nearby.
Cessna
- 327 Baby Skymaster - reduced scale four-seat version of the 337, with cantileverCantileverA cantilever is a beam anchored at only one end. The beam carries the load to the support where it is resisted by moment and shear stress. Cantilever construction allows for overhanging structures without external bracing. Cantilevers can also be constructed with trusses or slabs.This is in...
wings replacing the 336/337strut-braced configuration. It first flew in December 1967. One prototypePrototypeA prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
was built before the project was cancelled in 1968 due to lack of commercial interest in the design. The prototype was delivered to NASANASAThe National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
to serve as a full-scale model for wind tunnelWind tunnelA wind tunnel is a research tool used in aerodynamic research to study the effects of air moving past solid objects.-Theory of operation:Wind tunnels were first proposed as a means of studying vehicles in free flight...
testing. It was used in a joint Langley Research Center and Cessna project on noise reduction and the use of ducted versus free propellers. - 336 Skymaster - production version powered by two 195 hp Continental IO-360-A engines, 195 built.
- 337 Super Skymaster - 336; retractable undercarriageUndercarriageThe undercarriage or landing gear in aviation, is the structure that supports an aircraft on the ground and allows it to taxi, takeoff and land...
, redesigned nose cowlingCowlingA cowling is the covering of a vehicle's engine, most often found on automobiles and aircraft.A cowling may be used:* for drag reduction* for engine cooling by directing airflow* as an air intake for jet engines* for decorative purposes...
and new rear engine intake, and greater wing angle of incidenceAngle of incidenceAngle of incidence is a measure of deviation of something from "straight on", for example:* in the approach of a ray to a surface, or* the angle at which the wing or horizontal tail of an airplane is installed on the fuselage, measured relative to the axis of the fuselage.-Optics:In geometric...
, powered by two 210 hp Continental IO-360-C engines, 239 built. - 337A Super Skymaster - 337; minor detail changes, 255 built.
- - 337A; increased take-off gross weight, optional belly cargo pack, 230 built.
- T337B (1967) Turbo Super Skymaster - 337B; two Continental turbocharged fuel injected 210 hp engines which boosted service ceiling to 33000 feet (10,058.4 m), cruise speed to 233 mi/h, and range to 1640 miles (2,639.3 km)
- 337C Super Skymaster - 337B; new instrument panel and increased take-off gross-weight, 223 built.
- - 337C; minor detail changes, 215 built.
- 337E Super Skymaster - 337D; cambered wingtips and minor changes, 100 built.
- 337F Super Skymaster - 337E; increased take-off gross weight, 114 built.
- - 337F; split airstairAirstairAn airstair is a passenger staircase that is built in to an airliner — often, though not always, on the inside of a clamshell-style door. The stairs can be raised or lowered while the aircraft is on the ground, allowing passengers and ground personnel to board or depart the aircraft without the...
entry door, smaller rear side windows, improved flapsFlap (aircraft)Flaps are normally hinged surfaces mounted on the trailing edges of the wings of a fixed-wing aircraft to reduce the speed an aircraft can be safely flown at and to increase the angle of descent for landing without increasing air speed. They shorten takeoff and landing distances as well as...
, larger front propeller, powered by Continental IO-360-G engines, 352 built. - P337G Super Skymaster - 337G; pressurized cabin and turbocharged engines, 292 built.
- - 337G; minor changes and optional turbocharged engines, 136 built.
- P337H Pressurized Skymaster - T337G; minor changes, 64 built.
- 337M - US military version designated O-2 SkymasterO-2 SkymasterThe O-2 Skymaster is a military version of the Cessna 337 Super Skymaster utilized as an observation and forward air control aircraft...
in service, 513 built.
- O-2A - US military designation of the 337M Forward air control, observation aircraft for the US Air Force. 501 delivered to the USAF and 12 to the Imperial Iranian Air Force
- O-2B: Psychological warfare version for the US Air Force (31 former civil aircraft were converted to O-2B).
- O-2TT: Twin turboprop-powered version of the O-2.
- Summit Sentry O2-337 : Military version.
- Lynx: Armed military version for the Rhodesian Air Force.
- T337H-SP
Reims Cessna
- F337E Super Skymaster, 24 built.
- F337F Super Skymaster, 31 built.
- F337G Super Skymaster, 29 built.
- FT337G Super Skymaster, 22 built.
- F337H Super Skymaster, 1 built.
- FP337H Pressurized Skymaster, 1 built.
- FTB337G Milirole; military F337G with Sierra Industries Robertson STOL modifications and underwing hardpointHardpointA hardpoint, or weapon station, is any part of an airframe designed to carry an external load. This includes a point on the wing or fuselage of military aircraft where external ordnance, countermeasures, gun pods, targeting pods or drop tanks can be mounted.-Rail launchers:Large missiles and...
s, 61 built. - Lynx : RhodesiaRhodesiaRhodesia , officially the Republic of Rhodesia from 1970, was an unrecognised state located in southern Africa that existed between 1965 and 1979 following its Unilateral Declaration of Independence from the United Kingdom on 11 November 1965...
n designation for 21 FTB337Gs delivered to the Rhodesian Air Force.
Conversions/modifications
- Conroy StolifterConroy Stolifter-External links:**...
- an extensive single-turboprop engine STOL cargo plane conversion of the Skymaster. Front engine was replaced with a Garrett AiResearch TPE-331Garrett AiResearch TPE-331|-See also:-External links:* * *...
turbopropTurbopropA turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
; rear engine was deleted, and its space filled with an extended cargo pod. - AVE MizarAVE Mizar-External links:* * * * * -See also:...
- flying car, created by Advanced Vehicle EngineersAdvanced Vehicle EngineersAdvanced Vehicle Engineers of Van Nuys, California was an aviation company founded by ex-Northrop engineer Henry Smolinski in 1968 in order to develop a flying car....
, was an attachment of Skymaster wings, tail, and rear engine to a FordFord Motor CompanyFord Motor Company is an American multinational automaker based in Dearborn, Michigan, a suburb of Detroit. The automaker was founded by Henry Ford and incorporated on June 16, 1903. In addition to the Ford and Lincoln brands, Ford also owns a small stake in Mazda in Japan and Aston Martin in the UK...
PintoFord PintoThe Ford Pinto is a subcompact car produced by the Ford Motor Company for the model years 1971–1980. The car's name derives from the Pinto horse. Initially offered as a two-door sedan, Ford offered "Runabout" hatchback and wagon models the following year, competing in the U.S. market with the AMC...
outfitted with aircraft controls and instruments. - Summit Sentry - Summit Aviation re-manufactured existing used 337 airframes into the militarized O2-337 which includes four wing-mounted NATO standard pylons capable of carrying 350 lb (159 kg) each for 7.62 mm and 12.7 mm gun pods, rocket launchers, bombs, markers and flares. The aircraft was marketed for the target identification and marking, reconnaissance, helicopter escort and aerial photography roles. Examples were sold to the Haitian Air ForceArmed Forces of HaitiThe Armed Forces of Haiti, , consisted of the Haitian Army, Haitian Navy , Haitian Coast Guard, the Haitian Air Force, and some police forces . The Army was always the dominant service with the others serving primarily in a support role...
HondurasHondurasHonduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
, NicaraguaNicaraguaNicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...
, SenegalSenegalSenegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...
and the Thai Navy. The variant was still in production in 1987. - Spectrum SA-550Spectrum SA-550-External links:**...
- built by Spectrum Aircraft Corporation of Van Nuys, CaliforniaCaliforniaCalifornia is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, it was an extensive single-turboprop engine conversion of a Reims FTB337G constructed in the mid 1980s. They removed the nose engine, lengthened the nose, and replaced the rear engine with a turboprop.
Military operators
: Bangladesh ArmyBangladesh Army
The Bangladesh Army is the land forces branch and the largest of the three uniformed service of the Bangladesh Armed Forces. The primary mission of the Army is to provide necessary forces and capabilities in support of Bangladesh's security and defense strategies including defense of the nation's...
: Chilean Air Force
Chilean Air Force
The Chilean Air Force is the air force of Chile, a branch of the Chilean military.-History:The first step towards the current FACh was taken by Teniente Coronel Pedro Pablo Dartnell, when he founded the Servicio de Aviación Militar de Chile on December 20, 1910, being trained as a pilot in France...
Guinea-Bissau: Haitian Air Force
Armed Forces of Haiti
The Armed Forces of Haiti, , consisted of the Haitian Army, Haitian Navy , Haitian Coast Guard, the Haitian Air Force, and some police forces . The Army was always the dominant service with the others serving primarily in a support role...
: Imperial Iranian Air Force
: 8 x 0-2A
- 1 x 0-2B
: Military of Niger
Military of Niger
The Niger Armed Forces comprises both the military and national police services of the West African nation of Niger, totaling around 12,000 active personnel and 5,000 reservists...
: Paraguayan Air Force: 1 x 337RG
: Portuguese Air Force
Portuguese Air Force
The Portuguese Air Force is the air force of Portugal. Formed on July 1, 1952, with the Aeronáutica Militar and Aviação Naval united in a single independent Air Force, it is one of the three branches of the Portuguese Armed Forces and its origins dates back to 1912, when the military aviation...
(32 x FTB-337G) - Purchased in 1973 to replace the force's aging Dornier Do 27
Dornier Do 27
-See also:-Bibliography:*Green, William. Macdonald Aircraft Handbook. London. Macdonald & Co. Ltd., 1964.*Jackson, Paul A. German Military Aviation 1956-1976. Hinckley, Leicestershire, UK: Midland Counties Publications, 1976. ISBN 0-904597-03-2.-External links:**...
fleet, which had been used intensively in the Portuguese Colonial War
Portuguese Colonial War
The Portuguese Colonial War , also known in Portugal as the Overseas War or in the former colonies as the War of liberation , was fought between Portugal's military and the emerging nationalist movements in Portugal's African colonies between 1961 and 1974, when the Portuguese regime was...
. 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: South African Air Force
South African Air Force
The South African Air Force is the air force of South Africa, with headquarters in Pretoria. It is the world's second oldest independent air force, and its motto is Per Aspera Ad Astra...
: Republic of Korea Air Force
Republic of Korea Air Force
The Republic of Korea Air Force is the air force of South Korea...
: Sri Lanka Air Force
: Military of Swaziland
Military of Swaziland
The military of Swaziland is used primarily during domestic protests and has never been involved in a foreign conflict. Voluntary military service is open to all between the ages of 18 and 30...
: Royal Thai Navy
Royal Thai Navy
The Royal Thai Navy is the navy of Thailand and part of the Royal Thai Armed Forces, it was established in the late 19th century. Admiral Prince Abhakara Kiartiwongse is "The Father of Royal Thai Navy". Similar to the organizational structure of the United States, the Royal Thai Navy includes the...
: Togo Air Force
Military of Togo
The Military of Togo, in French FAT , consists of the army, navy, air force, and gendarmerie. Total military expenditures during the fiscal year of 2005 totaled 1.6% of the country's GDP. Military bases exist in Lomé, Temedja, Kara, Niamtougou, and Dapaong...
: United States Air Force
United States Air Force
The 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...
: Air Force of Zimbabwe
Air Force of Zimbabwe
The Air Force of Zimbabwe is the air force of the Zimbabwe Defence Forces. It was known as the Rhodesian Air Force until 1980. The Air Force of Zimbabwe saw service in the Mozambican Civil War in 1985 and the Second Congo War of 1998–2001....
