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Ramjet
High-speed aircraft maker Hermeus has revealed a ramjet-powered test vehicle that can be launched from under the wing of its supersonic Quarterhorse aircraft.
The unveiling of the Ramjet-X concept reveals a low-cost, expendable vehicle capable of high-speed flight to complement the reusable, Pratt & Whitney F100-229-powered Quarterhorse.
“Quarterhorse provides the reusable launch energy, while Ramjet-X provides a simple platform for testing at sustained high-mach speeds,” the company says in a news release.
The Ramjet-X, which is scheduled to begin integrated vehicle testing next year, builds on an element of the company’s original development plan.
Hermeus launched operations in 2018 with the goal of delivering a hypersonic aircraft powered by the Chimera, a turbine-based, combined-cycle (TBCC) propulsion system featuring a high-mach turbine engine that transitions to a ramjet.
The turbine-powered Quarterhorse and the ramjet-powered Ramjet-X repackages that TBCC into separately powered aircraft, while still building the company’s experience with both forms of propulsion.
“Ramjet-X gives us a way to put new systems into sustained high-mach environments without building an expensive one-off test program every time,” Hermeus CEO Zach Shore said.
The Defense Innovation Unit selected Hermeus nearly three years ago to support the High-Cadence Airborne Testing (HyCAT) program.
Hermeus demonstrated that the Quarterhorse Mk 2.1 unpiloted aircraft can release a missile-like store during flight. The follow-on Mk 2.2 version of Quarterhorse is expected to reach speeds of more than Mach 2, plus demonstrate a precooler system necessary for hypersonic flight.
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