John@sri-unix (06/22/82)
The 4000 mph that the X-15 could do is a long way from the 18,000 mph needed for earth orbit. At that speed the X-20 would have faced the same problem that the shuttle has: how to protect the craft from the heat of re-entry. The Boeing designers could have used Von Braun's solution, ablative shields, but with expendable shields and expendable boosters the only reusable part of the craft would be the cockpit. The only advantage I can see to that sort of design is being able to land it at different locations. This was more useful for military programs than civilian ones, which is probably why they ultimately decided not to bother. --------
ech (06/23/82)
True, we did NOT have the technologies in the early 60s to build the shuttle. But some of us who were around at the time got very upset with NASA/DoD for cancelling the DynaSoar (X-20) and going with non-reusables. Maybe that requires background. I cut my teeth on the visions of Willy Ley and others, who expected us to ENGINEER the conquest of space: build strong technological foundations as you went. Those visionaries expected the development of reusable low-earth-orbit technology followed by permanent manned LEO stations followed by (manned) exploration of the moon and the rest of the solar system, incorporating (are you ready?) APPROPRIATE TECHNOLOGY as it became available (ion jets, atomic engines, non-aerodynamic vehicles, etc.). The fact is largely forgotten now, but the initial NASA plan was for the Saturn V to be a SMALL PROTOTYPE for an order-of-magnitude larger booster designated Nova. Nova would have delivered a 75-ton Apollo package (command module, service module, lunar takeoff module, lunar landing module) directly from earth surface to lunar surface; that plan was scrubbed only when Gemini demonstrated that we really could accomplish rendevous. I don't retell this to ridicule, merely to illustrate the atmosphere at NASA in the early 60s: brute force was the default method, and the objective was not "get into space" but simply "beat the russians to the moon." Ah, water over the dam. My best hope now is that enough corporations will find LEO an enticing manufacturing environment that funding the shuttle, its successors, and permanent space facilities will simply be good business. Maybe I should learn Japanese... =Ned Horvath=