David.Smith@CMU-10A@sri-unix (06/24/82)
The X-20 wasn't called Dyna-Soar (Dynamic Soaring) for nothing. It was to be fully reusable, and didn't use ablative heat shields. The method of atmospheric entry was to come in at a shallow angle until it got hot, then to aerodynamically pull up, leaving the atmosphere to radiate the heat away. It would skip off the atmosphere many times as it slowed. When it was going slow enough, it would come on in. About ten years ago, I saw a drawing of a proposal North American Aviation had made for a Super-X-15. It was bigger than the existing ones; I don't know what they proposed to do for a heat shield. The drawing showed it being launched on top of an Atlas.
pcmcgeer (06/26/82)
Hmm. I suspected it might be something like that - the idea's been around for a long while - I guess that in 1982 it's even been a long while since the DynaSoar. Heinlein was using the Skip-to-M'Lou idea in the 40's. Why didn't the shuttle use the Dyna-Soar concept? Was it proved unsafe? Surely it must have been studied, since the tiles were giving such problems in the mid '70's that a lot of people were certain that the shuttle would never fly. Finally, if we can't make the DynaSoar work, is there any reason to suppose that the Russians can?