The British space agency has slapped the Australian one. There is only one reason – they are going to build a hypersonic space plane together. Both agencies have really optimistic plans. The machine should be able to handle the route New York – Great Britain in about one hour. The plane could theoretically have a speed of Mach 3,3 (which is more than three times the speed of sound). The engines should have similar fuel consumption as current airliners. So perhaps we are looking at a successor to the legendary Concorde, which reached a speed of "only" Mach 2. Concorde flew until 2003. The reasons were high costs, aggressiveness towards the environment, but also a tragic accident in 2000.
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Wow, that looks interesting.