King Air F90
A refurbished King Air F90. (All photos: Corrigan Air Center)

The Smaller 'Super' King Air

Although out of production for nearly 30 years, the King Air F90 is still highly sought after.

What do you do when an aircraft model is perfected? In at least one case, the answer was: you kill it. 

The murder mystery that is the Beechcraft King Air F90 can trace its roots back to the 1930s when Walter Beech introduced the Model 18, arguably the first cabin-class twin-engine business airplane. In 1958, Beech debuted the Queen Air, which remarkably resembles today's King Air, except for the square passenger windows and piston engines. By the late 1960s, Beech commanded a 77 percent share of the business twin-turboprop market. The company's efforts gave rise to an entire family of larger, more powerful business and commuter turboprops.

But as the King Air morphed into a multitude of models—including the 90, 100, 200, 300, and 350 and the 99 and 1900 series commuter airliners—the 90 series languished, growing gradually in heft and wingspan as it progressed through the alphabet until the F model arrived in 1979. The F was one of those rare parts-bin airplanes that actually works. Beech engineers took the fuselage of the C90 and combined it with the wing of the A100 and the T-tail from the B200 King Airs. Then they hung a pair of more powerful, Pratt & Whitney Canada P&WC PT6A-135 engines on it. Cruising speed jumped to 267 knots and the F90, and the slightly more powerful and faster F90-1 (with Dash 135A engines), were instant hits.

Eventually, 236 of them would be made (204 F90s between 1979 and 1983 and 32 90-1s between 1983 and 1986). But the 1981 recession and the growth of Cessna's Citation fanjet line tore the bottom out of the business turboprop market. And it didn't help that Beech had gone overboard with bifurcating its own product line and was then offering six King Air models, including three flavors of 90s. Some King Airs, like the F90 and the more expensive and larger 200, were perceived as competing directly against each other. 

The Knives Came Out

So, when defense conglomerate Raytheon took over Beechcraft in 1982, the knives came out. Even though the F90 sold 75 copies in 1981, it could not escape the actuary’s scrutiny. Despite a plethora of improvements incorporated into the F90-1 in 1983, by 1986 the company had reduced the number of available King Air models to three and begun steering prospective F90 customers up the food chain to the larger model B200. The F90 was toast, but the slower C90 remained in production.

Under new ownership 15 years later, Beech resurrected the concept of a “fast” 90 series King Air with its C90GT variant. Marketed as a “very light jet killer,” the $2.9 million aircraft afforded customers a time-tested design, a larger cabin with room for six to seven adults to sit comfortably, large oval windows, and pressurized baggage space capacious enough for several full-size roll-ons, hat bags, and many sets of golf clubs. You got a big main cabin door aft of the wing. You got a twin that sat high off the ground on beefy landing gear and was built like an M-1 Abrams tank. And you got an airplane you could land on an incredibly short and rough grass strip or a gravel bar without having to file an accident report afterward. 

In its first year of full production, the GT outsold its slower predecessor, the C90B, by almost two to one. The GT's new, more powerful Pratt & Whitney Canada engines delivered more speed and better high-altitude/hot-temperature performance and cut climb-to-altitude times by 35 to 50 percent. At full power, the big Hartzell four-bladed propellers rotated slower than on the C90B, reducing component wear and tear and, just as importantly, the decibels in the passenger compartment. And you got all this—at the time—for about the same price as a single-engine Pilatus PC-12 turboprop. 

But some purists, many of them owner-pilots, still seek out the comparatively more stylish, albeit aged, F90 models, which currently trade on the used market in the $800,000 to $1.4 million range, depending on vintage, updating, and condition. And the angst for the F90 arguably only grew when, in 2021, Textron Aviation decided to end King Air 90 series production entirely. While the 90 series kicked off the King Air line back in 1964, in recent years its appeal waned with buyers who could find similar performance from turbine singles including the Pilatus PC-12 and the upcoming Beechcraft Denali. Between 2004 and 2009, three C90 upgrades—GT, GTi, and GTx—progressively faded in popularity, even with the 2015 factory addition of Collins Pro Line Fusion touchscreen glass panel avionics. In all, 2,178 King Air 90 series were delivered before the plug got pulled. 

A Hard-to-find Model

Today, as a testament to its ongoing acceptance and limited production, finding a good F90 takes some doing. No more than a handful are for sale at any one time. Owners love this airplane. And it shows: A significant number of those that are available have been brought up to F90-1 specifications and beyond with the addition of aftermarket modifications from Raisbeck and others that include aft body strakes, engine inlets, aerodynamic exhaust stacks, Q-tip props, and nacelle wing lockers; Garmin digital/touchscreen-controlled avionics; and the PT6A-135A engine conversion from Blackhawk. 

Adding a ram air recovery system and the modified exhaust stacks alone can boost cruise speeds by up to 15 knots, to around 280. The 135A engines offer higher takeoff power and faster climb times, thanks to compressor and reduction gearbox differences. Even before the factory and aftermarket addition of the 135A engines, the F90 was already characterized as a “hot rod” due to its 200-shaft hp increase per side over an original C90 series King Air, allowing it to practically match the speed of the much larger King Air 200.

And, compared with the C90, it was a comfortable hot rod. While the two aircraft have almost exactly the same cabin dimensions and seven- to nine-passenger layouts (including aft lav), the improved pressurization system in the F90 translates into a sea-level cabin up to 11,000 feet and a 10,000-foot one at 26,000 feet. Optimum fuel burn is at 23,000 feet and the airplane can climb there within 10 minutes of takeoff. Overall fuel burn at cruise power is around 88 gallons per hour. Given the extra engine, this compares favorably with the single-engine PC-12NG, which burns around 63 gallons per hour. 

Even though some examples are closing in on being almost 44 years old, the F90’s indisputable value proposition remains today: it gets you there in style, almost as fast, and for less money than a King Air 200.

1981 Beechcraft King Air F90 at a Glance

Average used price: $932,000*

Crew: 1–2

Passengers: 7–9 

Cabin: 4 ft 6 in (W), 4 ft 10 in (H), 12 ft 5 in (L)

Baggage capacity: 54 cu ft (internal)

Engines: Pratt & Whitney Canada PT6A-135 turboshafts (2), 750 shaft hp each

NBAA IFR range: 941 nm (seats full) 

Maximum cruise speed (stock): 265 kt

Takeoff distance: 2,090 ft

Maximum takeoff weight: 10,950 lb

Service ceiling: 31,000 ft

*Source: Vref Online