Air Force-Backed Hypersonic Aircraft Startup Flies Demonstrator

Hermeus, a venture capital-backed company looking to develop a reusable hypersonic aircraft, announced March 3 it flew its Quarterhorse Mk 2.1 demonstration vehicle—its second successful flight in the last year.

The firm has also garnered interest from the Air Force and the rest of the Pentagon as the military looks to bolster its hypersonic portfolio.

The latest flight took off from Spaceport America over White Sands Missile Range in New Mexico, and operators flew Quarterhorse remotely from the company’s ground-based flight deck. The unmanned aircraft is about as big as an F-16 fighter and three times the size of its predecessor Mk 1, which flew for the first time last May.

“Hermeus’ Quarterhorse program follows a rapid, iterative development roadmap in which multiple aircraft are designed, built, and flown in quick succession—steadily increasing speed and performance,” the company said in a statement. “By continuously building and flying prototypes, the company uses real flight data to refine designs, reduce risk, and accelerate progress with each new aircraft.”

Part of an iterative development and test plan, the flight is a step toward Hermeus’ larger goal of mass-producing high-speed drones and passenger aircraft for both commercial and defense customers. In the near-term, officials have said the next goal is to fly the next iteration of Quarterhorse, Mk 2.2, at supersonic speeds.

“Speed is the fundamental requirement for our flight systems and for our company,” Hermeus CEO AJ Piplica said in a statement. “We’re building and flying aircraft on timelines that match the urgency of the world we’re in. Today’s flight kicks off a critical flight test campaign that will ultimately get us to supersonic speeds, bringing the United States closer to having the high-speed capability it needs now, not decades from now.”

The Defense Department has said the development of high-speed weapons and air vehicles is a high priority, naming “scaled hypersonics” as one of its six critical technology imperatives. In parallel to major weapons development programs, like the Air Force’s Air-Launched Rapid Response Weapon and Hypersonic Attack Cruise Missile, the department has also invested in startups like Hermeus who are maturing key technology that could be leveraged as part of future programs or used to help test capabilities for existing efforts.

In 2020, AFWERX, the Air Force’s innovation arm, awarded Hermeus a $1.5 million contract to study options for a future hypersonic Presidential and Executive Airlift fleet. The following year, Hermeus received a $60 million follow-on contract from the service to help the company build aircraft and ramp up its test program.

At the time, the Air Force said one of its goals for the investment was to broaden the defense industrial base for hypersonic propulsion systems and aircraft manufacturing. Beyond executive airlift, the service sees potential for mobility and intelligence, surveillance, and reconnaissance applications.

Quarterhorse is also part of the Defense Innovation Unit’s Hypersonic High-Cadence Airborne Testing Capabilities program, which is developing a hypersonic testbed using commercially available technology. Hermeus received a $23 million contract in 2023 to demonstrate propulsion systems, thermal management, power generation, and mission system capabilities that could be folded in to future DOD programs.

DIU’s HyCAT program notched its first flight on Feb. 27, when Rocket Lab’s HASTE launcher flew the DART AE testbed developed by Australian firm Hypersonix. The mission lifted off from Wallops Island, Va.

“The mission collected critical telemetry on the propulsion system, the flight vehicle, and real-time trajectory data to compare against simulated flight models,” DIU said in a statement. “The developed, tested, verified, and demonstrated additive manufacturing structural component designs and processes can now enable the supply chain behind Hypersonix to rapidly produce and deliver DART structural flight components, significantly increasing the availability rate of flight test vehicles.”