Hybrid-Electric Fan Component Enters Testing For Gambit 4

Gambit 4 artist’s rendering.

Credit: GA-ASI

RAF FAIRFORD, UK—The first component of a novel hybrid-electric propulsion system for a large, flying-wing uncrewed aircraft system (UAS) entered testing recently, setting the Gambit 4 program on course for an internally funded flight demonstration, a General Atomics Aeronautical Systems Inc. (GA-ASI) executive said on July 19. 

Blades of the first ducted fan thruster in the hybrid propulsion system are “spinning as we speak,” GA-ASI President David Alexander said during a Royal International Air Tattoo interview here.

“That part of the Gambit series is still out there and we want to make sure we don’t lose sight of that,” Alexander said.

The self-funded Gambit 4 demonstrator shares a name but little else with Gambit 1, a close derivative of the company’s winning concept for the first increment of the U.S. Air Force’s Collaborative Combat Aircraft (CCA). 

The design of the flying-wing Gambit 4 calls for demonstrating a 13,000-lb.-class flying wing UAS in 2026. By using a hybrid propulsion system based on a diesel engine, GA-ASI’s designers believe they can demonstrate a UAS capable of 60-hr., unrefueled flight. 

In the past, GA-ASI hinted that the hybrid-propulsion system could leverage GA-ASI’s experience with the diesel engine that powers the MQ-1C Gray Eagle-Extended Range for the U.S. Army. 

But Heavy Fuel Engine 2.0 in development for the MQ-1C Block 25 is not the basis for Gambit 4’s hybrid propulsion system, Alexander said in the July 19 interview. A different diesel engine with eight cylinders will be developed to generate the power for the electric motors in Gambit 4.

“It’s very unique,” he added.

Asked if the Gambit 4 could eventually become a member of the air superiority-focused CCA family, Alexander demurred. 

“I think it’s a different mission,” Alexander said.

Steve Trimble

Steve covers military aviation, missiles and space for the Aviation Week Network, based in Washington DC.