Skylon spaceplane pre cooler engine test. bbc News

1. Pre-cooler During flight air enters the pre-cooler. In 1/100th of a second a network of fine piping inside the pre-cooler drops the air’s temperature by well over 100C. Very cold helium in the piping makes this possible. 2. Jet engine Oxygen chilled in the pre-cooler by the helium is compressed and used to fuel the aircraft. In the test run, a jet engine is used to draw air into the pre-cooler, so the technology can be demonstrated. 3. The silencer The helium must be kept chilled. So, it is pumped thro