Quarterhorse

Hermeus Corporation · United States · first flew 2024 · fighter

Hermeus Quarterhorse is an unmanned hypersonic demonstrator aircraft targeting Mach 5+ speeds using a combined-cycle turbine-based engine that transitions between turbine and ramjet modes, designed to validate the company's propulsion and airframe technology for a future Mach 5 passenger aircraft.

Recognition (WEFT)

W — WingsLow-mounted, delta
E — Engines1 × turbofan, fuselage-mounted
F — FuselageBlended fuselage with ventral inlet for the combined-cycle engine
T — TailConventional

WEFT is AircraftIQ's four-point recognition method — how it works.

Spot it by:

Quarterhorse resembles other hypersonic demonstrators — sleek delta-winged body with a ventral intake, pointed nose, and minimal external stores. Its small size distinguishes it from full-scale hypersonic weapons or vehicles. Hermeus branding and the distinctive intake geometry are the primary identifiers in photographs.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

Atlanta-based Hermeus Corporation was founded in 2018 with the goal of developing hypersonic commercial aircraft. The Quarterhorse is the first in a series of subscale demonstrators — named after horse breeds in sequence — intended to prove the combined-cycle engine concept. Hermeus has USAF backing to develop the technology for potential military applications. Ground engine tests preceded the aircraft's first ground runs and anticipated 2024 test flights.

Variants

Quarterhorse is the first vehicle; subsequent Hermeus demonstrators are named Darkhorse and Halcyon (the proposed Mach 5 airliner). Each vehicle incrementally scales up speed and capability.

Where you'll see it

The Quarterhorse is a research and development demonstrator with no operational role. USAF Research Laboratory funding supports the programme as part of a broader interest in hypersonic vehicle technology.

Related aircraft

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