Overview

The Cessna 337 Skymaster is a six-seat piston twin produced from 1965 to 1980, built around an unusual push-pull centerline-thrust layout: one engine faces forward as a tractor, the other aft as a pusher, both on the fuselage centerline, with twin booms carrying the tail. The arrangement removes asymmetric thrust entirely, so an engine failure brings no yaw, no critical engine, and no V_mc hazard, which was Cessna’s answer to the most dangerous moment in conventional twin flying. The type also served the U.S. Air Force as the O-2 forward air control aircraft in Vietnam.

For a buyer, the Skymaster suits someone who wants genuine engine-out redundancy without V_mc exposure and will accept the trade-offs that come with it. The FAA rates it under a separate centerline-thrust multi-engine category, so it does not automatically qualify a pilot for conventional twins, and that niche shrinks the pool of instructors, insurers, and buyers. The late 337G and 337H (1973 to 1980) are the most developed versions, with electrohydraulic gear, an improved fuel system, and Continental IO-360-G engines; the specifications here reflect a representative late 337G/H on FAA TCDS A6CE.

Key Features for GA Buyers

• Centerline-thrust safety. The Skymaster’s signature is the complete absence of asymmetric thrust on engine failure. A single-engine emergency is a workload and performance problem, not a control problem. Single-engine climb is modest, roughly 300 fpm, but positive and predictable. For a buyer who wants genuine twin redundancy without V_mc exposure, the case is strong.
• Twin redundancy at modest fuel flow. The two IO-360-G engines burn about 22 gallons per hour combined in cruise, less than most conventional light twins, so you get two-engine redundancy without a cabin-class twin’s fuel bill.
• Visibility and cabin. The high wing and centerline engines give outstanding downward and lateral visibility, a major reason the O-2 was chosen for forward air control. The cabin seats up to six, though four with baggage is the practical mission.
• Useful load. The 337G/H carries roughly 1,500 lb of useful load, enough for its seats with meaningful fuel and baggage.

Trade-offs

• Maintenance complexity. Two engines, two propellers, a complex gear system, and difficult rear-engine access make the 337 a real maintenance commitment. Expect annual inspection costs around $4,000 or more.
• Rear-engine thermal load. The rear pusher runs hotter in its enclosed cowl and typically reaches the 1,500-hour TBO first. With two engines to overhaul at roughly $47,000 each, the reserve is significant.
• Wing spar inspections. A recurring FAA airworthiness directive requires eddy-current inspection of the wing spar caps (initial at 5,000 hours, then every 500 hours on non-pressurised airframes). Budget for it and confirm compliance status before buying.
• Not fast. Cruise of about 144 KTAS is unremarkable for a twin; the 337 trades speed for its safety concept. Buyers wanting more reach should look at the turbocharged or pressurised variants.
• Cabin noise. The rear propeller works in disturbed air, producing a loud, fatiguing cabin on long legs. Owners cite this as the airplane’s least pleasant trait.
• Niche rating and parts. The separate centerline-thrust rating shrinks the pool of qualified pilots, instructors, and insurers, and some type-specific parts require a specialist shop. Plan training and resale accordingly.

See Also

• Cessna P337 Pressurized Skymaster – the turbocharged, pressurised sibling; flight-levels comfort and near-200-knot cruise at higher cost and complexity. Compare
• Piper PA-34 Seneca – a conventional twin in the same class; faster cruise and a larger buyer pool, with the V_mc considerations the Skymaster avoids. Compare
• Beechcraft Baron 55 – a lighter, more affordable Baron; a common cross-shop for buyers weighing the safety concept against conventional twin performance. Compare
• Beechcraft Baron 58 – the larger, more capable Baron; stronger cruise and range at a higher price. Compare
• Cessna 310 – Cessna’s conventional cabin-class twin; more speed and payload, with full V_mc exposure on engine failure. Compare