Most people don't know this as the reports became public only in the last couple of years, but during the Challenger disaster only two of the seven astronauts died during the explosion. Anyone want to take a guess what the others died from? One suffocated and four died upon impact with Earth.
Most people also never took notice that astronauts starting wearing parachutes during shuttle launches. What old video footage and you will see that they all were them after the Challenger disaster, but not before. The shuttles were also fitted with an escape system to allow the crew to get out at mach insanity without being clipped by a delta wing.
My point is had this stuff been done earlier there might be five more astronauts alive today and it is theoretically possible to survive parachuting from the shuttle.