340A - Two 230kW (310hp) Continental TSIO-520-NB turbocharged and fuel injected flat six piston engines, driving three blade constant speed McCauley propellers.
335 - Two 225kW (300hp) TSIO-520-EBs.
340A - Max speed 452km/h (244kt), max cruising speed 425km/h (230kt), economical cruising speed 315km/h (170kt) at 25,000ft. Initial rate of climb 1650ft/min. Service ceiling 29,800ft. Range with reserves at economical cruising speed 2603km (1405nm), at max cruising speed 774km (418nm).
335 - Max speed 425km/h (230kt), max cruising speed 390km/h (211kt), economical cruising speed 313km/h (169kt). Initial rate of climb 1400ft/min. Service ceiling 26,800ft. Range at max cruising speed 2016km (1088nm), range at economical cruising speed 2542km (1372nm). Speed limits: flaps 15 deg. 160kts, flaps 45 deg. 142kts, gear down 140kts. Never exceed speed of 234kts.
340A - Empty 1780kg (3921lb), max takeoff 2719kg (5990lb).
335 - Empty equipped 1800kg (3963lb), max takeoff 2719kg (5990lb).
1287 340s and 64 335s were built. The 340 was in production between 1971 and 1984, the 335 between 1979 and 1981.
Six seat business twins
When released, the Cessna 340 joined the Beechcraft Duke as the only other six seat pressurised piston twin from a major manufacturer, positioned in Cessna's product line between the 310 and the eight seat 414 and 421.
Development of the 340 began in 1969, but the loss of the prototype early in 1970 set back the development program so that production deliveries did not begin until early 1971. The resulting aircraft borrowed heavily from other Cessna twins of the time including the wings from the 414 and the 310's undercarriage and a similar tail unit. Design features of the new aircraft included a pressurisation system with a differential of 0.29bars (4.2psi) that kept the cabin's internal altitude at 8000ft while the aircraft was at 20,000ft, an all new fail safe fuselage and an integral airstair door.
Initial production 340s were powered by two 210kW (285hp) turbocharged Continental TSIO-520-K engines, but these were replaced on the improved 340A, which was first introduced in 1976. Power for the 340A was supplied by two 230kW (310hp) TSIO-520-NBs, while other improvements included reduced diameter props and a slight increase in weights. The 340A was offered in optional 340A II and 340A III forms with various levels of IFR avionics fitted.
The Cessna 335 is an unpressurised, lighter weight and thus lower cost development of the 340. Available from 1979, aside from being unpressurised it differed in having 225kW (300hp) TSIO-520-EB engines. Although claimed by Cessna as the lowest priced cabin class business twin on the market, just 64 335s were built before production was terminated in 1980.