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Hermeus is moving forward with its goal of creating a hypersonic aircraft with the start of testing on the fully integrated vehicle, the Quarterhorse Mk 0. The small aircraft will not fly but rather be used for extensive development and testing to validate systems including electrical, hydraulic, avionics, pneumatic, propulsion and steering. The test vehicle will demonstrate remote command and control during taxiing.
The Quarterhorse will be the first aircraft Hermeus develops, used to demonstrate the Chimera engine's ability to transition from turbojet mode to ramjet mode during flight. The aircraft is 40 feet long and provides necessary development and testing learning to mitigate risk on future aircraft, the Darkhorse and Halcyon. When the Quarterhorse enters production it will be used for commercial testing and development purposes.
In 1971, an SR-71 flew over the Beale Air Force Base at 2,193.2 miles per hour. This flight broke the all-time jet-powered airspeed record and has not been broken since. If the Chimera engine can successfully transition from turbojet mode to ramjet mode in flight, Hermeus is hopeful the record can be broken. While the Quarterhorse will not rush to break the speed record, it is an important part of a strategy to develop three aircraft of increasing complexity.
The prototype risk testing will be spread out across multiple vehicles, enabling hermeus to learn more quickly. The Quarterhorse Mk 0 prototype resembles a standard iron bird but has an engine incorporated to demonstrate remote command and control during taxiing. Mk 0 will be a comprehensive test bed for the Quarterhorse and validate the many systems on the aircraft. The prototype will change the way testing is done, balancing experience with analysis and rigorous testing. The Mk 0 prototype will prepare Hermeus for taxi testing.
The next prototype, the Mk 1, is already taking shape in the factory. Hermeus said that designing, building and testing numerous aircraft simultaneously is the new normal. The Mk 0 is the dynamic iron bird, meant to "exercise the machine that builds the machine." The Mk 1 will be the first flight test vehicle, demonstrating autonomous takeoff and landing on a high-speed aircraft. The Mk 2 is expected to break the sound barrier and demonstrate autonomous supersonic flight below Mach 3. The fourth prototype, Mk 3, will demonstrate the turbojet to ramjet mode transition and break the 1971 aircraft airspeed record.RELATED STORIES:Hermeus accepts first Pratt andamp; Whitney F100 engineHermeus will integrate Pratt andamp; Whitney F100 turbofan into Chimera II hypersonic engineHermeus gives sneak peek of hypersonic uncrewed DarkhorseHermeus engine test hits ramjet mode
In June Hermeus announced it had received its first F100 engine from Pratt andamp; Whitney. The F100 engine is being integrated into the Chimera II turbine-based combined cycle propulsion system. With the F100 engine, the Darkhorse will be able to reach speeds of about Mach 2.8. In December 2022 Hermeus announced that the F100 turbofan, used in F-15 and F-16 aircraft, would be integrated into the Chimera II engine, just a week after unveiling the Darkhorse aircraft. Hermeus demonstrated the turbojet to ramjet transition on the Chimera engine in November 2022, which will be used in the Quarterhorse.
Hermeus anticipates beginning flight testing beginning soon.