That is why its so amazing that we never lost a man in space (not forgetting the 3 on the pad when they couldn't escape the burning capsule) until Challenger when computer power was so infantile. I wouldn't trust my computer to get me to Chicago, much less into and out of orbit 50 years ago. That's why it had to be test pilots, they had to make life or death decisions in a split second knowing they were sitting on top of souped up intercontinental ballistic missile. When they wanted to send up the chimp the line was so true where they say something like "the chimp doesn't know he may not come back." Outside of democracy and medical advances, I still believe escaping the gravity of earth is mans greatest achievement.