A thruster leak in the Skylab 3 crew’s Apollo command/service module forces NASA to consider a Skylab Rescue mission using a modified five-seater Apollo vehicle, mounted atop a Saturn IB and rolled out to the pad in readiness for the emergency flight. NASA brings in enough engineers and employees to have shifts working around the clock, seven days a week, to get the emergency mission ready for launch on September 9th. The thruster issue is later resolved, and the first-ever planned space rescue mission stands down. Astronauts Vance Brand and Don Lind are assigned to the rescue mission; both men later flew the Space Shuttle, though Brand will also fly in the Apollo-Soyuz Test Project. The modified command/service module and Saturn rocket are retained in case a rescue is needed for the final Skylab flight, and then as an Apollo-Soyuz backup vehicle, before being retired and displayed at the Smithsonian and Kennedy Space Center.