Piper PA-31-350 Chieftain

Overview

The Piper PA-31-350 Chieftain is the largest and most successful piston-twin commuter ever built, with 1,825 airframes produced from 1973 through 1984. Stretched two feet from the parent Navajo and uprated to 350 hp Lycoming TIO-540 / LTIO-540 counter-rotating engines, the Chieftain became the standard piston commuter twin during the deregulation era and remains in active freight and Part 135 operation worldwide.

The counter-rotating powerplant arrangement was the key engineering decision. The original Navajo’s conventional rotation produced a difficult critical-engine handling problem on engine-out, and the Chieftain’s mirrored propellers cured it. Combined with the 7,000 lb gross weight and 2,600+ lb useful load, the airframe set the template for high-density commuter and cargo operations that single-engine and lighter twins could not match.

Key Features for GA Buyers

• Heavy Hauler: Useful load above 2,600 lb supports a full passenger load with baggage, or roughly 1,500 lb of cargo at typical IFR fuel reserves. Few comparable-vintage piston twins approach this payload.
• Counter-Rotating Engines: Mirrored TIO-540 / LTIO-540 propellers eliminate the critical-engine handling problem that plagued the earlier Navajo, reducing single-engine accident severity and simplifying training.
• Cabin Volume: The 12.5 ft long, 4 ft wide cabin seats up to ten in commuter configuration, with a true cabin-class entry door and headroom that piston-twin owners often rate above pressurized competitors.
• Operator Support: Nearly 1,825 built and decades of Part 135 service mean parts, mechanics, and type-experienced instructors are widely available, a meaningful advantage over rarer cabin-class twins.

Trade-offs

• Fuel Thirst: Cruise burn of approximately 43.6 GPH at 75% power is roughly double a piston single and well above the 310 hp Navajo. Charter and freight economics depend on filling seats or cargo to keep the per-mile cost reasonable.
• Engine Costs: Lycoming TIO-540 overhauls run approximately $25,000 per engine, with the J2BD-series cylinders historically prone to shock-cooling damage. Disciplined power management is critical to reaching the 1,800 hr published TBO.
• Unpressurized: Service ceiling is 24,000 ft, but most operations cruise FL120 to FL180. Long-haul comfort suffers compared to the pressurized Mojave or Cheyenne siblings.
• Maintenance Complexity: Turbocharged, geared engines plus hydraulic gear and flap systems generate higher annual costs than owner-flown light twins. Budget commercially even for private operation.

See Also

• Piper Navajo PA-31 – the 310 hp parent type the Chieftain stretched from. Compare
• Piper PA-31T3-500 T-1040 – the turboprop sibling on the same fuselage, with PT6A-11 engines. Compare
• Piper PA-31P-350 Mojave – the pressurized piston sibling for higher-altitude weather avoidance. Compare
• Cessna 402 – the direct commuter piston twin competitor from Wichita. Compare
• Beech 58 Baron – the lighter cabin-class piston twin alternative for owner-flown missions. Compare