Hartzell Earns FAA Type Certificate for First Part 35 Electric Engine Propeller

Hartzell Propeller has received FAA Part 35 Type Certification for the first propeller designed specifically for advanced air mobility (AAM) aircraft.

The company worked with aerospace company BETA Technologies to achieve this, conducting all testing of its propeller on BETA’s proprietary electric propulsion systems (electric engines), which are designed and manufactured in-house by BETA. 

Hartzell’s propeller is the first to earn FAA type certification specifically for integration with electric propulsion systems. These systems, like BETA’s, are capable of managing a wide range of different loads and conditions—from regenerative braking to startup.

The approval comes after thousands of hours of ground and flight testing over four years and verifies that the propeller exceeds the performance and safety standards of FAA Part 35.

This is an endorsement from the FAA of the efficacy and safety of Hartzell’s propeller, as well as the performance of BETA’s electric engines, which provided the foundation for its testing.

“Hartzell Propeller is very pleased to work with BETA Technologies on this AAM breakthrough development,” said Hartzell President JJ Frigge, “Our design specifically for BETA Technologies is a five bladed, carbon fiber, ground adjustable fixed pitch propeller that will have future applications for the entire AAM industry.”

Hartzell and BETA have worked on the propeller development since 2021, from initial aerodynamic modeling and design to full-scale testing and validation. The result is a high-performance, low-noise propeller tailored specifically for electric engines and this next generation of aviation.

BETA will utilize Hartzell’s propeller to optimize the performance and safety profile of both its ALIA VTOL and ALIA CTOL aircraft. The propeller is also built to serve all AAM aircraft that utilize similar electric propulsion systems.

“With its decades of experience across all types of aircraft, Hartzell Propeller has understood from the beginning the unique challenges and opportunities of electric aviation,” said Kyle Clark, founder and CEO of BETA Technologies.

Clark added, “Their engineering precision and deep certification experience have assisted us as we bring this aircraft to market and walk through our own certification steps. We’re proud to have been their counterpart on this project and look forward to getting this certified propeller in the air as we continue the process of certifying our electric engines, as well as our ALIA CTOL and VTOL.”

BETA has been flying its ALIA CTOL and ALIA VTOL aircraft with Hartzell’s propellers for more than four years, including completing the industry’s first crewed transition of an eVTOL and several long-range flights with its fixed-wing, including a coast-to-coast trip across the U.S. and now a Grand Tour of Europe.