Hawker Beechcraft (HBC) hopes to boost new C90-series King Air sales with another revision of its smallest twin turboprop. Deliveries of the $3.65 million King Air C90GTx will begin early next year. The GTx will offer significant increases in payload and range along with improved turbulence-detecting Doppler weather radar and Waas GPS capability as standard equipment.

The GTx replaces the current $3.3 million C90GTi, launched in 2007. The aircraft are remarkably similar save for the avionics up- grades and BLR composite wing-lets on the GTx. The new winglets render some significant performance improvements: maximum ramp weight and mtow both increase by 385 pounds, from 10,160 to 10,545 pounds and from 10,100 to 10,485, respectively, and maximum payload with full fuel almost doubles from 387 to 737 pounds. Range also increases: with four passengers the GTx will fly 200 miles farther than a GTi at both long-range and high-speed cruise power settings. High-speed cruise range increases from 865 to 1,060 nm while long-range cruise increases from 980 to 1,195 nm. Like the GTi’s, the GTx’s ceiling will effectively be limited to 28,000 feet due to the lack of an RVSM solution for the aircraft. The winglets also are expected to improve climb performance. The GTi currently can climb to FL240 in 17 minutes at 140 knots.

Powerplants will be unchanged. The GTx shares the same 3,600-hour-TBO P&WC PT6A-135As that are on the GTi producing 750 shp each (550 flat-rated) and top speed remains unchanged at 270 knots. GTx avionics remain the Rockwell Collins Pro Line 21. The GTx modifications will be available for retrofit on older C90s through two separate STCs, from BLR for the winglets and Centrex Aerospace for the weight increase, available together or separately and installed by Hawker Beechcraft Services beginning this fall. Price for the modifications was not disclosed. A Hawker Beechcraft spokesman also said it is likely that certain upgraded cabin styling and features incorporated into the larger Beechcraft King Air 350 and 200 series would at some point be available on the GTx.

Initial-run GTx C90s will have some minor interior changes.

In the cockpit, the pilots’ control yokes will be changed and replaced with more ergonomic ones from the Premier 1A. The multifunction display will be LED backlit and video capable. Plans are also in the works to upgrade the avionics with synthetic vision. The one-hour cockpit voice recorder will be up-graded to record for two hours. In the cabin, 110-volt electrical outlet plugs will be available for laptops and other personal electronics.