BRIAN NELSON, CNN ANCHOR: Except for the tragic case of the Challenger, NASA's shuttle program has gone with such ease that it's tempting to take the whole thing for granted. CNN's space correspondent Miles O'Brien brings us a close-up look at the mind- boggling array of nuts and bolts and procedures that go into each and every single shuttle launch.</s>MILES O'BRIEN, CNN SPACE CORRESPONDENT (voice-over): The solid rocket boosters are carefully inspected. The huge blimp-like external fuel tank is hoisted into place. The three main engines are removed and inspected in a gleaming engine shop.</s>UNIDENTIFIED MALE: Pull me up a little further, Joe.</s>O'BRIEN: The $1 million toilet is gingerly hoisted into place. The landing gear cycled, and after months of painstaking preparation, a new tile is glued onto that wing flap. After combing through the old paperwork, engineers determine workers used the wrong sized liner when they attached the tile six flights ago. This is good news, as there is no reason to suspect a problem that would ground the fleet. And suddenly, it occurs to me that pile of paperwork might be worth its weight.</s>UNIDENTIFIED MALE: Attention -- left, please.</s>O'BRIEN: Nearly nine months after she came home to roost, Discovery is ready to leave the orbiter processing facility. It's a milestone moment, slightly bittersweet for the OPF crew.</s>COLLEEN ADAMS, SHUTTLE PAYLOAD CHIEF: When you start understanding how the whole thing operates, it becomes a lot more than an orbiter or just a piece of equipment. It becomes something exciting. You know, you're watching it launch, and you receive it back. And, you know, you get to go through this process -- you can see where it got hurt on its journey, you know, and you get to repair it, you know. So it turns into, you know, a living entity.
NASA Checks Out Every Spacecraft Thoroughly