Engine Tests For Rotating Detonation Ramjet A series of engine tests demonstrating the viability of a liquid-fueled rotating detonation ramjet for use in hypersonic missiles is underway between GE Aerospace and Lockheed Martin. The companies conducted direct connect tests in ramjet ignition and cruise conditions at the GE Aerospace Research Center in Niskayuna, New York, to demonstrate the operation of an air-breathing rotating detonation ramjet for missile applications. This is the first initiative between the companies under a broader joint-technology development arrangement.