SpaceShipTwo and Dynasoar (and the Soviets)
ShockWave77598 commented that SpaceShipTwo resembles the Dynasoar vehicle. He should know -- and he's right:
Here's a write-up describing these early efforts. The Dynasoar prototype was canceled in 1963 (thought testing continued for some time into the following year).
Dynasoar (or X-20) would ride into orbit on a launcher such as the Titan III-C. It would re-enter the atmosphere in the same manner as the space shuttle ultimately did decades later.
One significant difference: SpaceShipTwo does not (and cannot) reach orbit, so the launch and re-entry energies involved are only a fraction of what Dynasoar had to content with. (On the order of 10% or so.)
A friend suggested that SpaceShipTwo resembled even more closely an early Soviet Myasishchev spaceplane concept, but I wasn't able to see one with a strong similarity. The closest I found was the BKA-23, or Design #48 (from about 1958):
(Forget the Russian-to-English translation on this site: about the only phrase that makes it through is "hair drier". Perhaps they're referring to the rocket engine.)
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