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"Here you go:

RTLS: Return to Launch Site

An engine fails within the first few minutes of flight, or a systems problem (cabin leak, loss of cooling, etc.) occurs which requires the shuttle to come home early. In this case, the shuttle will fly downrange a bit, and then do a flip: it's originally travelling east, with the ET on "top" (away from the earth). During this flip maneuver, the shuttle will rotate so that its nose and tail swap places, and at the end the shuttle is flying backwards into is own exhaust, with the tank on the bottom. Eventually this will negate all of its forward momentum, and start to move back towards KSC. Then it's just a matter of dropping the ET and gliding back to the Cape. The whole thing takes about 25 minutes.

TAL: Transoceanic Abort Landing

If a problem occurs after the last RTLS capability, then the shuttle will have to land on the other side of the Atlantic. Depending on inclination, this will be either in Africa (Ben Guerir, Morocco) or Spain (Zaragoza or Moron). A TAL takes about 35 minutes."

OK, Captain Science, explain -- using one and two syllable words, because I must be slow -- how we do a RTLS or a TAL after Main Engine Cut Off.

Or are you saying that we should always opt for an abort scenario if anything, even slightly off-nominal occurs during ascent? Remember, this incident occurred 80 seconds into the flight. That gave the launch team a whole 280 seconds to recognize (a) that something had happened, (b) that it was serious enough to jeprodize crew safety, especially since (as I understand at this point) the event was picked up on a camera that was only analyzed after the launch phase was over.

Further, these types of incidents had happened before. I remember on STS-1 watching the first shots of the camera from the cargo bay and seeing tiles missing from the OMS pods. Other missions had returned safely with tiles missing or -- as on the Glenn flight -- the parachute door missing. And insulation chunks had hit the Orbiter before. (I think that was one reason they were going to the new tank design.)

I suspect that when we are done, the tiles are going to be found to have been just one of the factors involved. That three or four otherwise innocuous problems -- including with tiles -- combined to cause a catastrophic failure. Remember Challenger? On that flight the SRB leak just happened to be over the strut holding the SRB to the ET. The leak melted the strut, allowing the SRB to swing in, hit the tank and rupture it. If the leak had been on the other side of the SRB, it would have been just a minor anomaly -- noticable as a pressure drop in the left SRB, but otherwise not noteworthy.

Keep your shirt on. Sheeesh.

OK, Captain Science, explain -- using one and two syllable words, because I must be slow -- how we do a RTLS or a TAL after Main Engine Cut Off.

Why don't you ask NASA, they developed the contingencies.

My reading of this is that the MECO would now happen immediately after SRB separation.

I already asked if they had accelerometers on board whose data could be telemetered to ground. I would bet they do have many accelerometers since they would like to know that at least the main engines were healthy before attempting orbit after SRB separation. The accelerometers should be able to detect a significant impact, they do it on all jet engines very successfully.

Remember Challenger? On that flight the SRB leak just happened to be over the strut holding the SRB to the ET. The leak melted the strut, allowing the SRB to swing in, hit the tank and rupture it. If the leak had been on the other side of the SRB, it would have been just a minor anomaly -- noticable as a pressure drop in the left SRB, but otherwise not noteworthy.

The leak grew rapidly in width. The interior pressure in the SRB was 1000 PSI. The hot exhaust gasses were only kept in by 2 rubber "o" rings and some magic putty. The leak was forming an area where the sections were no longer attached to each other. How many seconds would it have taken for the leak to get so wide that the booster sections seperated? Not many I suspect.

I dont recall how much burn time they had left, but looking at the videos it seems they had a lot of fuel left after the explosion.