The Cessna Skymaster is an innovative twin-engine civil utility aircraft built in a push-pull configuration. Instead of the engines being mounted on the wings, one is mounted on the nose and the other at the rear of the pod-style fuselage. The stabilizers are mounted on twin booms that extend from the wings. The rear engine is between the booms. With this "centerline thrust" configuration the aircraft is much easier to handle on one engine than a conventional configuration. The combination of a tractor and a pusher engine produces a unique unmistakable sound. Enthusiasts have no doubt when they hear a Skymaster fly over.
Development
The first model of the Skymaster was the 336. It had fixed landing gear and first flew in February 1961. It went into production in 1963 and 195 were produced to mid 1964.
In 1965 Cessna introduced the model 337 Super Skymaster. This aircraft was larger, had more powerful engines, retractable landing gear and a dorsal air scoop for the rear engine (the "Super" was subsequently dropped from the name). In 1967 the turbocharged T377 was introduced and in 1972 the pressurized T377G entered production. Cessna built 1,859 standard and turbocharged Skymasters and 332 T337Gs. In addition, they built 513 military O-2 versions.
Cessna production ended in 1980 but Skymaster production continued with Reims in France with the FTB337 STOL and the military FTMA Milirole. Reims produced a total of 94 Skymasters.
After a 20-year hiatus the centerline thrust, pod and twin-boom concept has been revived in the Adam A500.
Operational history
The US Army used the O-2 variant as a Forward Air Controller platform during the Vietnam War.
The California Division of Forestry uses the O-2 variant as spotter planes during firefighting operations.
In 1994 the Cuban exile group Hermanos al Rescate (Brothers to the Rescue) used Skymasters to drop life-saving supplies to rafters attempting to cross the Florida Straits to defect from Cuba. They chose Skymasters because they were eaiser to control at slow speeds than conventional twin-engine aircraft. One plane contacted the water (it is difficult to judge altitude over relatively calm water), damaging the landing gear doors and the nose propeller. Since the rear engine is mounted higher, it wasn't damaged and the aircraft was able to return to Florida to make a belly landing.
Variants
Cessna 336
Cessna 337
- 337A
- 337B
- 337M - US military version, designated O-2 Skymaster in service
- O-2A
- O-2B
- O-2T - turboprop-powered O-2
- 337C
- 337D
- 337E
- 337F
- 337G
- 337H
- T337B - turbocharged engines
- T337C
- T337D
- T337E
- T337F
- T337G
- T337H
Reims F337
- F337
- F337P - pressurized
- FTB337G - STOL version
Flying car created by Advanced Vehicle Engineers by attaching the wings, tail, and rear engine of a Skymaster to a Ford Pinto outfitted with aircraft controls and instruments.
Summit Sentry
Summit Aviation built a militarized Skymaster as the O2-337 in 1980, and sold a few examples to the Haiti Air Corps and the Thai Air Force
Spectrum SA-550
Spectrum Aircraft Corporation of Van Nuys, California made an extensive conversion of a Reims FTB337G in the mid 1980s - the Spectrum SA-550. They removed the nose engine, lengthened the nose and replaced the rear engine with a turboprop. This aircraft (serial number 61) is currently registered to Basler Turbo Conversions of Oshkosh, Wisconsin.
Special Characteristics
The Skymaster has different handling characteristics than a conventional twin-engine aircraft. Foremost is that it will not yaw into the dead engine if one engine quits. Consequently, it has no tendency to depart the runway if an engine fails on the takeoff roll. The adage, "dead foot, dead engine" -- used to remind a pilot which propeller to feather when an engine quits -- is useless with the Skymaster. When a Skymaster loses power, the pilot must use the instruments to determine which engine has failed. The Skymaster is also controllable at lower airspeeds than a comparable conventional twin. There is no minimum controllable speed advisory (Vmc) on the airspeed indicator.
Nevertheless, the Skymaster requires a multi-engine-rated pilot. The pilot must be trained to manage both engines, and must also be trained to handle the special characteristics of a multiengine aircraft with centerline thrust .
One would think that with the Skymaster's superior single-engine handling it would have a lower accident rate than conventional twins. This turns out not to be true. The rear engine tends to overheat and quit while taxiing on very hot days. When this has happened, many pilots have inexplicably attempted take-off on the nose engine alone even though the single-engine take-off roll exceeded the runway length. The Skymaster also has a higher-than-average rate of accidents due to fuel mismanagement. This is puzzling since the fuel system is unremarkable.
The Skymaster produces a unique unmistakable sound. All rear-engined aircraft produce a characteristic sound as the propeller slices through turbulent air coming off the airframe. Since the Skymaster also has a nose engine, with a propeller that operates in undisturbed air, its sound is different from a pure pusher.
Specifications (337D)
General Characteristics
- Crew: one, pilot
- Capacity: five passengers
- Length: 29 ft 9 in (9.07 m)
- Wingspan: 38 ft 0 in (11.58 m)
- Height: 9 ft 4 in (2.84 m)
- Wing area: 201 ft² (18.7 m²)
- Empty: 2,655 lb (1,204 kg)
- Loaded: lb ( kg)
- Maximum takeoff: 4,400 lb (1,995 kg)
- Powerplant: 2x Continental Motors IO-360 -C, 210 hp (157 kW) each
Performance
- Maximum speed: 200 mph (320 km/h)
- Range: 764 miles (1,223 km)
- Service ceiling: 19,500 ft (5,945 m)
- Rate of climb: 1,200 ft/min (366 m/min)
- Wing loading: lb/ft² ( kg/m²)
- Power/Mass:
External links
Related content
Related development:
AVE Mizar
Comparable aircraft:
Adam A500
Designation sequence:
318 -
320 -
335 -
336 -
337 -
340 -
401 -
402
Variants:
O-2 Skymaster
