Hermeus targets lower-cost high-Mach testing with reusable Quarterhorse launch aircraft and expendable Ramjet-X test vehicle

Hermeus is developing Ramjet-X, an expendable ramjet-powered test vehicle scheduled for integrated flight testing in 2027 from the reusable Quarterhorse aircraft. Quarterhorse will accelerate and climb to the launch condition normally supplied by a large disposable booster, then return for reuse while Ramjet-X continues in sustained high-Mach flight. Under a flight-test-as-a-service model, customers could install sensors, communications equipment, computing, autonomy software, materials or propulsion experiments without developing a dedicated high-speed vehicle. Engine work is under way at Hermeus' Jacksonville test site and high-temperature structures at El Segundo; no customers, prices or exact performance targets were announced.