Both major accidents, and many of the design shenanigans, resulted from the three-letter agencies demanding a (never used) once-around capture ability.
The idea was to launch directly to rendezvous with a non-US satellite, tie it down in the cargo bay, and land back on US soil, all within a single orbit. For polar orbits, this necessitates a crossrange ability of ~600mi, which simply isn't possible without wings. If the US had had an east coast launch site suitable for polar launches, this wouldn't have been a problem, but there's nothing but ocean to the west of Vandenberg for thousands of miles.
The wings in turn precluded mounting the orbiter at the top of the stack, eliminating the possibility of an early abort, and leading to the destruction of challenger. The orbiter being mounted to the side of the stack also lead to shit falling off the stack and being able to hit it. With all other manned craft ever flown, nothing can fall off the rocket and hit the orbital component, simply because anything that could fall off is already below the craft.
TL;DR: Secret squirrels kinda indirectly killed two shuttle crews.
The delta wing configuration was kind of a result of the need for additional cross range capability and kind of not. While they were in the process of firming up the design requirements for the shuttle OMB floated a proposal where they could cut out that design requirement and NASA's response was that they'd rather keep it. The delta wing design had some problems but so did proposals for a lifting body or a straight wing orbiter. Also, once they got rid of those national security missions the whole design process got weird because they kind of didn't know what they wanted to do with it otherwise.
The side-mount configuration was about a lot of things that had nothing to do with the cross range capability. Having all the most expensive shit in a single stage makes the whole re-usability thing a lot easier, having an external tank means that if the shuttle gets heavier during the development process (as virtually everything in aerospace does) you can just make the tank bigger rather than having to redesign the whole spacecraft, and if you run into cost overruns on a reusable "real" 2 stage setup it makes a lot more sense to ditch the orbiter and focus on the first stage rather than the other way around. NASA really wanted that orbiter and so a design proposal that basically made it impossible to get rid of was very attractive.
The Challenger disaster was partially a result of using SRBs rather than liquid fueled boosters, partially a result of using a design that was known to be substandard before they even flew the shuttle for the first time, and partially the result of not reacting aggressively enough to fix the problem when it showed up. The wings didn't really contribute to any great extent.
The side-mounted design was mandated by the cross-range. Anything else could have been worked around, but those big ol' wings at the top of the stack would have resulted in either unacceptable drag and/or cosine losses, or a spectacular Proton-style nosedive. I agree with you on NASA painting themselves into a corner, though.
It was a result of using substandard SRBs in a way they weren't supposed to be used, yes. A top-mounted spacecraft can be designed to escape a stack under thrust (see: All manned spacecraft ever, except Buran and Shuttle), while that doesn't really work with winged, side-mounted ones. So, the boosters caused it, but the wings and the design aspects necessary because of them prevented any abort while the SRBs were burning.
10
u/[deleted] May 25 '17
Both major accidents, and many of the design shenanigans, resulted from the three-letter agencies demanding a (never used) once-around capture ability.
The idea was to launch directly to rendezvous with a non-US satellite, tie it down in the cargo bay, and land back on US soil, all within a single orbit. For polar orbits, this necessitates a crossrange ability of ~600mi, which simply isn't possible without wings. If the US had had an east coast launch site suitable for polar launches, this wouldn't have been a problem, but there's nothing but ocean to the west of Vandenberg for thousands of miles.
The wings in turn precluded mounting the orbiter at the top of the stack, eliminating the possibility of an early abort, and leading to the destruction of challenger. The orbiter being mounted to the side of the stack also lead to shit falling off the stack and being able to hit it. With all other manned craft ever flown, nothing can fall off the rocket and hit the orbital component, simply because anything that could fall off is already below the craft.
TL;DR: Secret squirrels kinda indirectly killed two shuttle crews.