It was a twin-engined development of the PA-24 Comanche single-engined aircraft. A variant with counter-rotating propellers was designated the Piper PA-39 Twin Comanche C/R. The Piper PA-30 Twin Comanche (later PA-39) was designed as a twin-engined variant of the Piper PA-24 Comanche. A complex light twin, with retractable landing gear, seating 4 (in original models) to 6 (in later models), and cruise speeds ranging from 160-210 mph on twin 150-160 horsepower engines, it competed with the more-powerful Cessna 310 and Beech Baron, and later with Piper's other light twins. The normally aspirated aircraft was equipped with two 4-cylinder 160 hp (120 kW) Lycoming IO-320-B1A fuel injected engines, but 200 hp (150 kW) engines were available as a modification by Miller Aviation. A version with turbocharged engines for higher altitude flight was also developed, using IO-320-C1A engines of the same nominal power. All Twin Comanche engines have long times between overhaul (2000 hours for the B1A, 1800 for the IO-320-C1A) and have developed a reputation for reliability. The Twin Comanche is a low-wing cantilever monoplane with a retractable tricycle landing gear. With tip tanks, the aircraft holds 120 gallons (454 L) of fuel. Fuel burn at typical cruise settings is approximately 16 gal/h (58.7 L/h) with a cruise speed of 165 kn. It easily climbs to 18,000 feet (5,500 m) when desired (24,000 feet (7,300 m), if turbocharged). When compared with the Seminole, the Twin Comanche goes faster, carries more, burns less fuel, climbs more rapidly and ultimately higher, is quieter. When compared to the Seneca, which is really quite a different aircraft, the more noticeable differences are in handling. Another contemporary competitor to the Twin Comanche was the Beechcraft Travel Air. A similar airplane in form and function was the Gulfstream American GA-7 Cougar, which went into production after the Twin Comanche's production run ended. For operational history and details of the three models and eight variants. click here. Specifications below are for the PA-39 C/R counter rotating variant.
