Turboprop engine-upgrade company Blackhawk Modifications this week announced progress toward a supplemental type certificate (STC) that will boost performance in the workhorse Beechcraft King Air 350.
The Waco, Texas-based company recently submitted a flight test plan to the FAA for the engine upgrade that will replace the original Pratt & Whitney 1,050 shp PT6A-60A engines with the high-performance 1,200 shp PT6A-67A. Blackhawk expects testing to begin in November and the finalized STC to be received in May. The initial STC will cover King Air 350s with a max gross weight of 15,000 lbs. Once the initial STC is complete, Blackhawk will turn its focus to the heavier version of the twin turboprop.
The XP67A Engine+ program also includes a five-blade propeller upgrade with either an MT or Hartzell propeller.
Operators who make the upgrade can expect a cruise speed increase of about 37 ktas, bringing the max cruise up to 340 ktas at maximum engine power limits. In addition to more power, the upgrade provides increased range and better climb performance in hot temperatures. The significant increase in climb performance is a major safety enhancement, particularly for military operators aiming to get away from enemy fire as soon as possible, said Bob Kromer, Blackhawk's senior vice president of engineering.
“In my 10 years at Blackhawk, I have test flown every engine upgrade that we have put on the market,” said Chris Dunkin, Blackhawk’s regional sales manager and chief pilot. “I can confidently say that the XP67A engine has the most impressive performance that I’ve seen by far.”