@S1-A.ARPA,@MIT-MC.ARPA:KENNER@NYU-CMCL1.ARPA (07/31/85)
From: (Richard Kenner) <KENNER@NYU-CMCL1.ARPA> I have a question about the programming of the Shuttle abort procedures. While listening to yesterday's ATO, I heard a "1 engine TAL" call a while after the ATO started. I assume that this meant that had a second engine failed before that point, the Shuttle would be in what is politely called a "contingency abort" situation where crew servival is problematical. My question is this: In this case, the engine was shut down due to a perceived (the last I heard they didn't know whether it was real or not) increase in temperature of the high-pressume fuel pump in Engine #1 past the red-line point. However, suppose a second engine developed the same condition prior to the "one engine TAL" call. Shutting down this second engine would now be questionable. Shutting it down would almost certainly result in crew loss while leaving it running would merely incur a probability of crew loss. The proper thing to do in this circumstance would probably be to leave the engine running until 1-engine TAL capability was reached. However, it is my understanding that the precise determination of abort capability is not done on-board but is done in MCC. Does anyone know how this case is handled? How about if two engines simultaneously had red-line problems (suppose they were in different areas) in a state where there was a 2-engine survivable abort but no 1-engine survivable abort? Does the software assess which perceived red-line is more dangerous and shut down the appropriate engine? Or are both engines lost (and hence the crew)? -------
alb@alice.UUCP (Adam L. Buchsbaum) (08/02/85)
The shuttle, believe it or not, is designed to float for a while in water. So a water landing, assuming its controlled, does not necessarily mean doom for the crew. An engine blowing up, though, almost certainly does (if you've ever seen the films of the explosions encountered when the ME's were in testing phase, you know what I mean). Also, the shuttle can land on any runway that is at least 10,000 feet long. This means almost every major airport in the world. Of course, it's not the most desireable situation, but again, it beats and explosion. In short, in any circumstance I can think of, I would think NASA would want to make an emergency landing somewhere rather than risk a blowup.
rjnoe@riccb.UUCP (Roger J. Noe ) (08/02/85)
> From: (Richard Kenner) <KENNER@NYU-CMCL1.ARPA> > > I have a question about the programming of the Shuttle abort procedures. > While listening to yesterday's ATO, I heard a "1 engine TAL" call a while > after the ATO started. That's "one-engine TAO" for Transatlantic Abort. Should they lose a second engine before that call, they'd get very wet. But I'd rather be in a shuttle orbiter landing on the ocean surface than in an airliner. -- Roger Noe