Compression lift
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In aerodynamics, compression lift refers to an aircraft that uses shock waves generated by its own supersonic flight to generate lift. This can lead to dramatic improvements in high-speed regimes, where lift is often hard to come by.
The basic concept of compression lift is not uncommon, "planing" boats reduce drag by "surfing" on their own bow wake in exactly the same fashion. Using this effect in aircraft is more difficult, however, because the "wake" does not generate until supersonic speeds, and is highly angled. In order to take advantage of the potential lift, aircraft have to be carefully shaped to take full advantage of this effect. In addition the angle of the shock waves varies greatly with speed, making it even more difficult to design a craft that gains significant lift at anything other than a single speed.
To date the only production aircraft that used compression lift is the XB-70, although in the end it too ended up being a testbed only. The amount of lift from compression effects on this craft are debatable though. Designs dedicated to using compression lift, waveriders, remain an interesting possibility for hypersonic vehicle designs, although only testbed models have been flown.