11
$\begingroup$

There were many studies in the 1960s, and a lesser number of later ones, for launch vehicles with nuclear-thermal upper stages. I have rarely seen mention of what emergency procedures were considered for launch failures.

Dangers of launching a nuclear thermal rocket suggests the hazard is not extreme - for the case of an NTR started in orbit. A nuclear upper stage has the possibility of running for some time but failing to reach orbit.

Even in the pre-Chernobyl era, there has to have been serious consideration of this. What studies were done, and is there any available summary of the results?

$\endgroup$
  • 1
    $\begingroup$ You may want to include studies of space-based reactors, which were more numerous (and were actually deployed!), into the consideration. Basically, robust reactor shielding and de-spinning (maintaining positive attitude control) are your best friends. $\endgroup$ – Deer Hunter Feb 14 '15 at 21:51
  • 1
    $\begingroup$ Remember that a nuclear-thermal engine doesn't have a huge mass of stuff just looking to go boom. While it certainly could crash it's not going to go up in an approximation of a tactical nuke. Furthermore, the real danger is used rods, not fresh ones. $\endgroup$ – Loren Pechtel Feb 14 '15 at 21:51
  • 1
    $\begingroup$ Nukes, schmukes. Real rocketeers use liquid fluoride and hydrazine. $\endgroup$ – Deer Hunter Feb 14 '15 at 23:42
  • $\begingroup$ A bit about "poison wires" to prevent criticality from water getting inside the pressure vessel: sciencemadness.org/lanl1_a/lib-www/la-pubs/00397413.pdf $\endgroup$ – Deer Hunter Feb 15 '15 at 0:01
3
$\begingroup$

50 years old abort routines are hard to come by, but the NERVA-specs (unclassified 9/8/1970) clearly specify a malfunction mode in which the engine should be able to provide a minimum of thrust and impulse. The values stated (thrust of 30000 pounds, impulse of 10⁸ lb-seconds) are enough to direct the upper stage away from densely populated areas, towards a landing in the ocean. The engine should also be capable of operating with just one turbo pump
Normal procedure for saving the crew during a launch failure is separating the capsule from from the rocket, and fire a solid rocket escape tower to get away, followed by a normal descent with parachutes. The Mercury capsules, pre-dating the NERVA program, was equipped with escape towers.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.