The Blackhawk Group Awaits Pending STC Approval for Hartzell 5-Blade Composite Propeller Paired with XP67A Engine+ Upgrade on the King Air 350

OSHKOSH, WI – July 21, 2025 – The Blackhawk Group has officially submitted all flight test data to the Federal Aviation Administration (FAA) and is awaiting Supplemental Type Certificate (STC) approval for the highly-anticipated integration of Hartzell Propeller’s advanced 5-blade composite propeller with Blackhawk’s powerful XP67A Engine+ Upgrade for King Air 350 aircraft.

This milestone STC unlocks a transformative performance package that delivers unmatched speed, efficiency, and operational value—further cementing The Blackhawk Group’s legacy of innovation in aftermarket upgrades for legacy turboprops.

Hartzell’s 5-blade composite propeller features state-of-the-art carbon fiber construction, offering a lighter-weight, more durable alternative to the standard 4-blade aluminum propeller. Each side of the aircraft sheds approximately 10 pounds with the new design, totaling 20 pounds in weight savings. The reduced diameter also significantly lowers cabin and exterior noise, while enhancing comfort and operational efficiency.

Paired with Blackhawk’s XP67A Engine+ Upgrade—replacing the stock PT6A-60A engines with 1200 SHP PT6A-67A powerplants—the combination provides a 24% increase in available horsepower. Operators can expect impressive performance metrics including cruise speeds exceeding 337 KTAS, rapid climbs to FL350 in under 18 minutes, and dramatically improved takeoff and climb performance.

The XP67A has been in service for over 8 years and continues to demonstrate remarkable reliability and improved performance across a wide range of operating environments, including high and hot conditions. This STC approval represents not just an innovation in performance, but an expansion in optionality—giving customers more choices to tailor their aircraft for mission-specific needs through a vast network of service facilities around the world. Very few companies revisit and expand STCs once approved, but Blackhawk is committed to providing continued value and utility for our operators. This dedication underscores our mission: always improving the outlook for our customer base.

“This STC approval is a major step forward for King Air 350 operators seeking to elevate the performance of their aircraft without the cost of a new airframe,” said Edwin Black, President of TBG’s Proprietary Upgrades division. “By combining Hartzell’s cutting-edge propeller technology with our proven XP67A engine upgrade, we’re offering a next-level solution that maximizes value, performance, and long-term ROI.

”The Hartzell composite propeller has been tested extensively with over 50,000 flight hours, 20 lightning strike simulations, and more than 200 bird strike tests. It boasts unlimited blade life and a proven track record of reliability across global fleets. The result is increased fuel efficiency, reduced maintenance demands, and maximized uptime for operators.

“We’re proud to launch this game-changing 5-blade carbon fiber propeller STC for Blackhawk-powered King Air 350’s,” said JJ Frigge, President of Hartzell Propeller. “It’s the ultimate performance upgrade-lighter, quieter, and engineered for maximum thrust and ramp appeal. Operators can now unlock the full potential of their Blackhawk conversion with unmatched efficiency and style.”

With this STC, Blackhawk will provide a customizable upgrade path for King Air 350 owners looking to modernize their aircraft and achieve jet-like performance at a turboprop cost. The Hartzell 5-blade propeller/XP67A upgrade pairing is available to new and existing Blackhawk King Air 350 customers. Blackhawk-modified King Airs routinely sell at or above the combined value of their airframe and upgrades, making this a sound investment for operators thinking about the long-term.

Operators are encouraged to reserve their delivery position today by contacting Blackhawkat +1 (254) 755 6711 or info@blackhawk.aero.

For more information about the Hartzell 5-Blade Composite Propeller upgrade and the XP67A Engine Upgrade, visit The Blackhawk Group this week at EAA AirVenture (booth #322) or online at www.blackhawk.aero.