First, let's talk about scramjets. These have air-breathing engines (like turbofans and piston engines), so they don't need to carry a supply of oxidizer to combust their fuel. This makes them lighter and more efficient than rocket propelled missiles, as well as being more maneuverable. The first open source image of a Chinese scramjet test emerged in December 2015. It flew to an altitude of 30 kilometers (over 18 miles), and reached a Mach 7 speed. Interestingly, while American scramjet tests have generally been air dropped before firing their rocket boosters, the Chinese scramjet test was boosted from a land-based launcher. Scramjets could enable more efficient and easier forms of space launch and hypersonic airliners, just as they could be used for high-speed cruise missiles to replace ballistic missiles.