[TalonDJ]

That unstable yaw gimbal was looked at very carefully before giving them a “go”.

It seems a far cry from later. "Oh yeah stuff falls off and hits the heat shield all the time. A problem? Beats me. Probably not. Maybe. What do you mean Columbia's wing burned off? Oops. I guess we should have paid more attention."

[chimera]

Well, FWIW, when I first saw the design for the shuttle, that was my first thought. It was like, man, that heat shield is hanging out there like that, unprotected, for the entire duration of the flight, especially powered flight through the atmosphere during ascent. That had never been done before. Up until then, all of our spacecraft kept their heat shields covered and protected until just before they were used (Apollo 13 had its heat shield briefly uncovered between SM jettison and LM jettison, which caused considerable concern at MCS, but they had no choice, they had to do it that way, they needed the LM for maneuvering prior to re-entry). With Columbia, the damage had already been done, they had no repair kit, no way of knowing what the damage was, no way to get back to the ISS. I have a sneaking suspicion the switch from freon-based insulating foam to the more eco-friendly form that tended to crack and flake a lot more had something to do with it, but I have no scientific proof of that, and it is considered decidedly un-PC to suggest this is so, especially in the NASA era of no spaceflight, but plenty of “Muslim outreach”.