Beechcraft Bonanza Turbine

Overview

The Soloy Turbine Bonanza (later marketed as the Tradewind Turbine Bonanza) is an after-market conversion of the Beechcraft A36 Bonanza in which the Continental piston engine is replaced by an Allison/Rolls-Royce 250-B17 free-turbine turboprop under FAA STC SA3523NM. Soloy Aviation earned the original STC in 1986 with the 250-B17C, rated at 420 shaft horsepower for takeoff. Tradewind Turbines acquired the STC in 1989 and upgraded the installation to the 450-shaft-horsepower 250-B17F/2; Soloy reacquired the certificate in 2016 and is the current STC holder. The airframe remains the A36 (FAA TCDS 3A15), so the structural airspeed limits, six-place cabin, and gross weight are inherited from the piston Bonanza; only the powerplant and fuel system change.

A buyer chooses a turbine A36 when the goal is turboprop reliability, hot-and-high performance, and Jet-A operation in a familiar Bonanza airframe, without stepping up to a larger, pressurized factory turboprop. The turbine adds roughly 40 to 50 knots of cruise over a piston A36 and transforms field and climb performance, at the cost of a high acquisition premium and a payload penalty from the extra fuel the turbine burns. Choose the Turbine Bonanza when you already value the Bonanza platform and want turbine dispatch reliability and altitude capability, and can accept an unpressurized cabin and forty-plus-gallon-per-hour economics in exchange.

Key Features for GA Buyers

• Allison/Rolls-Royce 250-B17 turboprop. The free-turbine engine offers a 3,500-hour TBO and turbine dispatch reliability in place of the piston Continental, and runs on Jet-A.
• Strong field and climb performance. The turbine A36 cruises near 200 to 215 KTAS in the mid teens and climbs well above piston Bonanza rates, with markedly shorter takeoff distances.
• Familiar A36 airframe. Six-place cabin, club-seating layout, and Bonanza handling are retained; the conversion is an engine and fuel-system change on a type-certificated airframe, not a new airplane.
• Tip-tank fuel option. Tradewind conversions commonly add tip tanks to supplement the 74-gallon main fuel and preserve range against the turbine’s higher burn.

Trade-offs

• High acquisition premium. The conversion historically ran into the several-hundred-thousand-dollar range on top of the donor A36, placing total cost near used factory turboprops.
• Unpressurized at turbine altitudes. The A36 cabin is not pressurized, so the turbine’s altitude capability is limited in practice by oxygen requirements above the mid teens.
• Fuel burn versus piston. Cruise burn is roughly 24 gallons per hour of Jet-A, far above a piston A36, and full fuel cuts into payload.
• Finite STC support. The conversion depends on a single STC holder for parts and engineering support rather than a factory production line.

See Also

• Beech Bonanza A36 – the piston A36 airframe this conversion is built on. Compare
• Beech Bonanza 36 (Turbo) – the turbocharged piston A36 for high-altitude piston cruise. Compare
• Beechcraft Bonanza G36 – the modern factory-production piston Bonanza on the same airframe. Compare
• Piper M500 – a pressurized factory single-engine turboprop cross-shop. Compare
• Socata TBM 700 – a pressurized factory single-engine turboprop one class up. Compare