Apollo, Soyuz and Orion have used, are using or will use launch escape towers. If it is not needed, it must separate during flight. What if it does not separate? I suppose that the spacecraft would drop its upper stage and land. But these spacecrafts use parachutes to land. Isn't the launch escape tower in their way? And is it safe to land with the added mass of the escape launch tower?

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    $\begingroup$ The answer is no (can't land), but I am stumped for a reference. $\endgroup$ Commented Sep 4, 2016 at 12:05
  • $\begingroup$ Plasma + solid fuel booster. What could go wrong ? $\endgroup$
    – Antzi
    Commented Sep 4, 2016 at 17:01
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    $\begingroup$ For Apollo, there would have been no mission while the escape tower remained in place, because it would prevent docking with the LM. There would also be no safe landing while the escape tower was in place because the parachutes could not be exposed. $\endgroup$
    – Anthony X
    Commented Sep 4, 2016 at 21:08
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    $\begingroup$ The redundant explosives on the bolts holding the shuttle stack to the pad failed on one mission. But I agree, I suspect the reason that this failure wasn't in the Apollo flight rules is that it was deemed non credible. $\endgroup$ Commented Sep 5, 2016 at 12:54
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    $\begingroup$ CST-100 does not have a tower universetoday.com/wp-content/uploads/2013/07/MTF10-0014-05.jpg It uses a pusher abort system americaspace.com/wp-content/uploads/2014/08/CST100-capsule.jpg $\endgroup$ Commented Sep 5, 2016 at 21:35

1 Answer 1


That'd no doubt interfere with the reentry, and the deployments of the parachutes. I suspect they'd call an abort slightly after the failure and maybe actually use the tower to escape, but I'm guessing there. Perhaps it'd be risky to activate it if didn't get jettisoned correctly, who knows how it is remaining attached..

Details on redundancy jettison operations from apollo sim: http://nassp.sourceforge.net/wiki/Launch_Escape_System

And links at the bottom of that page to official docs.

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    $\begingroup$ Apollo mission rules (hq.nasa.gov/alsj/a17/A17MissRules.pdf) p. 123 paragraph H don't list failure of LES to separate as an abort recommendation. $\endgroup$ Commented Sep 4, 2016 at 18:40
  • $\begingroup$ So what do they do then, carry it to the moon and back? How do they dock with the lem? $\endgroup$
    – Innovine
    Commented Sep 4, 2016 at 18:50
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    $\begingroup$ If you can get into orbit, a contingency EVA is a potential option to get it loose. Sounds hairy though. $\endgroup$ Commented Sep 5, 2016 at 4:14
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    $\begingroup$ Calling an abort after the escape system failed to jettison would probably be a mistake - because they wouldn't be able to use the parachutes! I think @pericynthion is right, they would have to get safely into orbit then devise a way to separate the escape system and any shrouds manually, to free the rest of the spacecraft. $\endgroup$
    – Andy
    Commented Sep 5, 2016 at 7:53
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    $\begingroup$ The LES was pretty heavy, I suspect a significant performance impact would be included with all the other issues. $\endgroup$ Commented Sep 5, 2016 at 12:57

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