[1]: 1–1 [4] Astronauts Vance Brand and Don Lind were assigned as the rescue crew, in the event of the mission's necessity.

A rescue mission was considered when the Skylab 3 Command/Service Module (CSM) developed problems in its reaction control system (RCS) thrusters while docked to the station.

[5][6] After a rescue mission in Earth orbit was depicted in the 1969 film Marooned, the company revived the concept in November 1970.

[2] Marshall Space Flight Center issued a formal Mission Requirements document on 17 May 1972, with subsequent revisions.

To convert the standard CSM to a rescue vehicle, the storage lockers were removed and replaced with two crew couches to seat a total of five crewmen.

[7] NASA considered bringing the crew home immediately,[3] but because the astronauts were safe on the station with ample supplies and because plans for a rescue flight existed,[8]: 209  the mission continued while the Saturn IB rocket AS 208 with CSM 119[4] was assembled in the Vehicle Assembly Building at Launch Complex 39 for possible use.

[1]: 2–6 [8]: 208–209  The astronauts would attempt to prepare Skylab for further use but returning experimental data and diagnosing the cause of the problem were more important,[1]: 2–1  with Lind choosing what would be brought back.

The crew, likely consisting of Brand, Lind, and Skylab backup Science Pilot William B. Lenoir, would have performed some scientific research and closed out the station until the Space Shuttle was operational.

This was in support of the design and construction of a similar system on the new Orion spacecraft, which resembles the Skylab Rescue configuration.