Blackhawk Modifications (Booth No. 2935) has received supplemental type certificate (STC) approval of its XP28 upgrade for the Piper Cheyenne I with Pratt & Whitney Canada PT6A-28 engines in place of the original PT6A-11s. The new engines will allow power to be carried to a much higher altitude and increase speed to 250 ktas.

The bolt-on $475,000 conversion uses freshly overhauled or time-continued P&WC PT6A-28 or variant -28 models that have been converted from PT6A-21 or PT6A-11 engines. New four-blade Hartzell or McCauley propellers are optional. A new flight manual supplement and performance charts are included. The XP28 upgrade is available from any of Blackhawk’s dealers.

Blackhawk also announced it has received more than 12 deposits for its XP(42A) Cessna Grand Caravan engine upgrade, for which it anticipates FAA approval next year.  The upgrade replaces the stock PT6A-114A engine with an 850-shp PT6A-42A, providing an additional 175 shp in all phases of flight.

The company predicts the modification will enhance performance, including reducing takeoff distances by 45 percent, doubling climb rate, increasing cruise speeds by 35 to 40 knots and increasing (via a kit) approved mtow by 300 pounds to 9,062 pounds.