The King Air F90 and F90-1 were produced between 1979 and 1985. The F90s were faster than their predecessors, thanks to a more powerful version of the Pratt & Whitney PT6 engine.
The F90 actually is a “hybrid” King Air in that it combines the fuselage and wings of the King Air E90 with the T-tail of the King Air 200. The F90 is powered by PT6A-135s, utilizes Hartzell four-blade propellers to reduce noise, was the first King Air to incorporate a multi-bus electrical system, and has an enhanced pressurization system that provides a sea-level cabin to higher than 11,000 feet.
Deliveries of the F90 began in mid-1979 and continued through 1983, when the F90-1 was introduced. The F90-1 features PT6A-135A engines, which provide improved performance compared to the PT6A-135 that powers the F90. While both powerplants are flat-rated to 750 shaft horsepower, the -135A offers 885 shaft horsepower at max takeoff power, compared to 850 shaft horsepower for the -135. The F90-1 also has redesigned low-drag cowlings. A Collins avionics package, including the APS-80 autopilot, was standard equipment.
Seattle’s Raisbeck Engineering offers a number of popular performance products for the F90, including the Raisbeck/Hartzell quiet turbofan propeller system, dual aft-body strakes, high-flotation gear doors (for F90s equipped with high-flotation landing gear), and nacelle wing lockers.
Blackhawk Modifications provides a bolt-on engine upgrade for the F90 that involves replacing the aircraft’s original PT6A-135 powerplants with factory-new PT6A-135As. Benefits include increased true airspeed, rate of climb, and single-engine service ceiling—along with decreased time and fuel to climb, lower operating costs, and increased resale value.
A total of 236 aircraft (203 F90s and 33 F90-1s) were built, and 137 remain on the FAA registry. Current Vref prices for the aircraft range from $725,000 for a 1979 Model F90 to $1,225,000 for a 1985 Model F90-1.
Robert A. Searles is a writer specializing in commercial, military, and general aviation.
King Air F90
King Air F90-1