Ursa Major wins $28.5 million Air Force contract to flight-test Draper engine for hypersonic use

Join our newsletter to get the latest military space news every Tuesday by veteran defense journalist Sandra Erwin.

WASHINGTON — Rocket propulsion startup Ursa Major Technologies has secured a $28.5 million contract from the U.S. Air Force Research Laboratory to conduct the first flight test of its Draper engine, a storable, high-performance propulsion system tailored for hypersonic missile applications.

The contract, announced May 1, covers both the flight demonstration and integration of the engine into a test vehicle, with work scheduled through early 2027. The project aims to advance U.S. capabilities in hypersonic weapons, a category of defense systems that has become a top Pentagon priority amid competition with China and Russia.

The Draper engine is designed to produce 4,000 pounds of thrust and was developed by Ursa Major with U.S. Air Force funding. Its key differentiator is its use of storable, non-cryogenic propellants — specifically a kerosene and hydrogen peroxide combination — that remain liquid at ambient temperatures. This contrasts with traditional rocket engines that rely on liquid oxygen, which must be kept at ultra-low temperatures and handled with complex cooling infrastructure.

The military is especially interested in quick-launch capabilities for interceptor missiles, including those envisioned for the Golden Dome missile defense architecture. The framework, introduced in a January executive order by the Trump administration, aims to establish a layered U.S. missile shield capable of intercepting high-speed threats such as hypersonic glide vehicles and maneuverable cruise missiles.

Hypersonic glide vehicles can travel at more than five times the speed of sound and steer mid-flight. Their speed and maneuverability are driving demand for agile propulsion systems that can enable both offensive and defensive platforms.

Based in Berthoud, Colorado, Ursa Major completed ground tests of the Draper engine in 2024. The company, which also makes the 5,000 pounds-of-thrust Hadley engine for hypersonic test vehicles, has emerged as an independent supplier of rocket engines that, unlike other propulsion providers in the U.S. aerospace and defense sector, is not part of a large, vertically integrated prime contractor.