Hermeus Ramjet-X air-launched from Quarterhorse for repeatable Mach 4 tests

Hermeus unveiled a two-vehicle architecture where a reusable Quarterhorse drone releases an expendable ramjet test vehicle (Ramjet-X) at ~Mach 3 so it can accelerate to ~Mach 4/100,000 ft. The novelty is using a reusable high-speed carrier to replace single-use boosters, enabling higher-cadence, lower-cost hypersonic/ramjet flight testing and potentially "flight test as a service" for sensors, comms, autonomy, and materials payloads.