Hypersonic developer Hermeus has begun testing a proprietary pre-cooler technology that will allow a standard Pratt & Whitney F100 jet engine to operate at higher speeds and with greater efficiency.

Between Mach 2 and Mach 3, the turbojet transitions to a ramjet engine, which powers the plane at hypersonic speed. “That's actually pretty tricky and pretty difficult,” Case said.

The Japan Aerospace Exploration Agency is to fire a subscale hypersonic pre-cooled turbojet engine called S-Engine by August in preparation for a 2009 flight test. After its firing at Taiki ...

At low speeds, Chimera is in turbojet mode – just like any jet aircraft. At higher speeds, Chimera bypasses the incoming air around the turbojet and the ramjet takes over completely. Chimera utilizes ...

COLORADO SPRINGS—Hypersonic aircraft developer Hermeus has started tests of its pre-cooler system with the Pratt & Whitney F100-229 engine, which will power the company’s Quarterhorse Mk. 2 ...

Hermeus will use a modified version of the 29,000-lb. thrust engine, which also equips the Boeing F-15 and Lockheed Martin F-16, to power the 45-ft.-long uncrewed aircraft from a standing start on ...