https://www.space.com/41123-darpa-experimental-spaceplane-military-engine-test.html?utm_content=buffer32755&utm_medium=social&utm_source=facebook
The engine for the space plane
(https://img.purch.com/h/1400/aHR0cDovL3d3dy5zcGFjZS5jb20vaW1hZ2VzL2kvMDAwLzA3Ny82Njkvb3JpZ2luYWwvQVItMjItSnVuZTI3LmpwZz8xNTMxMjUwNTQy)
DARPA selected Boeing to build a reusable space plane, called Phantom Express, propelled upward with Aerojet Rocketdyne's engine — a version of which was the space shuttle's main engine. Before this, that engine had only been re-fired within 24 hours once before.
This test helps validate the idea of a reusable spacecraft with a quick turnaround that's closer to that of an aircraft, officials said during today's discussion. Phantom Express is designed to launch vertically, releasing a disposable second stage at between 200,000 and 300,000 feet (60,000 to 90,000 meters) to deploy a satellite into orbit, Wierzbanowski said, before the space plane glides to the ground for a smooth landing. It should be able to release more than 3,000 lbs. (1,360 kilograms) into orbit for a cost of less than $5 million per flight — and the first test flight of the system is currently set for 2021.