UK-based Reaction Engines has carried out a series of tests on a key component for its new engine, the Sabre, which is capable of operating as both a jet and a rocket engine by employing a translating intake. The novel feature will enable the aircraft–such as the Skylon reusable spaceplane–that the Sabre will power to fly anywhere on earth in less than four hours or directly into space and back to deliver satellites or cargo. The third and final demonstration using groundbreaking technology–an air pre-cooler–will start in August.