Blackhawk STCs 5-blade Prop on XP67 Engine+ Upgrade

The FAA has approved a supplemental type certificate (STC) for Blackhawk Group’s integration of the Hartzell five-blade composite propeller on the King Air 350 XP67A Engine+ upgrade. That powerplant modification replaces the original Pratt & Whitney Canada PT6A-60A engines with 1,200-shp PT6A-67As.

Weighing about 10 pounds less than the four-blade aluminum propeller, the carbon-fiber five-blade propeller has a smaller diameter, reducing cabin and exterior noise. Development of the composite propeller included more than 50,000 flight-test hours, 20 lightning-strike simulations, and more than 200 bird-strike tests, according to Blackhawk.

The -60A engines provide a 24% increase in available horsepower, pushing cruise speeds to above 337 knots and improving takeoff and climb performance, with the ability to climb to FL350 in less than 18 minutes.

“This STC approval is a major step forward for King Air 350 operators looking to elevate performance without buying a new airframe,” said Edwin Black, president of Blackhawk’s Proprietary Upgrades division. “By pairing Hartzell’s composite propeller with our XP67A upgrade, we are delivering a powerful, efficient solution with strong ROI.”