lunar lifeboat

Noun

 * 1)  In the US Apollo moon program, a lunar module repurposed as a makeshift shelter for an astronaut crew returning to earth after a mishap necessitating cancellation of a moon landing; the emergency procedure of using the lunar module in this manner.
 * 2) * 1970,, "The Flight of Apollo 13—A Successful Failure," Society of Experimental Test Pilots Technical Review, vol. 11, no. 1, p. 130 (Google search result) (retrieved 30 July 2015) :
 * At 141 hours and 30 minutes, the Lunar Module, Aquarius, after successfully fulfilling its contingency role as a Lunar Lifeboat, was jettisoned in preparation for the final plunge into the Earth's atmosphere.
 * 1) * 1970 Sept., Steven Morris, "How Blacks View Mankind's “GIANT STEP”," Ebony, p. 35 (Google preview) (retrieved 30 July 2015) :
 * As the "lunar lifeboat" neared the Earth, the hard problem loomed of how to separate the vehicles before they entered the atmosphere.

Usage notes

 * Almost always used in reference to the mission (1970), the only real-world instance in which a lunar lifeboat was used.