General Atomics Completes Qualification Test for New 200-Horsepower Engine for Gray Eagle Drone

General Atomics Aeronautical Systems, Inc. (GA-ASI) has completed the final qualification test for its new 200-horsepower Heavy Fuel Engine (HFE) 2.0 at its El Mirage, California, flight facility.

This milestone marks the end of a comprehensive three-week test program aimed at validating the engine’s durability and performance. The HFE 2.0 engine is designed to support the demanding requirements of the Gray Eagle 25M unmanned aircraft system (UAS) for Multi-Domain Operations (MDO).

The HFE 2.0 engine is a low-maintenance power source with a 40 percent increase in service life compared to its predecessors, providing longer maintenance-free operational periods. This engine will deliver the necessary horsepower and electrical power for the Gray Eagle 25M, ensuring the UAS can meet the rigorous performance standards for MDO missions.

Aligned with the Federal Aviation Administration’s (FAA) endurance test requirements, the HFE 2.0 underwent an extensive qualification process. Over 18 months, the engine completed 2,450 full power cycles, simulating high-stress conditions through test profiles of 200, 400, and 651 hours. Additionally, the engine completed 50 hours of flight testing across a broad flight envelope, further confirming its reliability.

Developed through GA-ASI’s internally funded research and development program, the HFE 2.0 engine is the result of collaboration with General Atomics Europe and propulsion technology innovator Cosworth. The engine features a dual brushless generator designed and built by General Atomics Electromagnetic Systems. This generator is expected to reduce field maintenance and provide over 50 percent more electrical power, supporting the expanded payload capacity required for MDO missions.

Following the completion of the FAA engine endurance test, the next step is the U.S. Army certification process, which will authorize the HFE 2.0 for use on the Gray Eagle Extended Range (GE ER) UAS. This will replace the existing 180-horsepower engine, which is nearing the end of its service life. Additionally, the HFE 2.0 engine will be the cornerstone of the modernized Gray Eagle 25M, which is currently being produced under a U.S. Army-funded program to support future MDO UAS missions.