Among last-ditch options considered for the Apollo programme (specifically several planned but eliminated long-duration, two-week missions), was the ultimate LE

Among last-ditch options considered for the Apollo programme (specifically several planned but eliminated long-duration, two-week missions), was the ultimate LESS-is-more approach: "Lunar escape systems". This was basically a lawn-chair rocket for two which would utilise a disabled LEM's (lunar excursion module) fuel tanks, and would be hand-piloted without any guidance computer to an intercept orbit with the Apollo Command Module, with the hope that a rendezvous and crew transfer could occur within the four-hour window of space-suit oxygen supplies. Given that the CM's orbital period was two hours, this meant at best two chances for a successful intercept. <https://en.wikipedia.org/wiki/Lunar_escape_systems https://en.wikipedia.org/wiki/Lunar_escape_systems> (I'd run across this from the recently submitted MOOSE article, "Man out of space, easiest", a strap-a-foam-mattress-to-your-ass reentry concept: <https://en.wikipedia.org/wiki/MOOSE https://en.wikipedia.org/wiki/MOOSE>.)