Apollo 13 - Repairs in Progress

To save the lives of the flight crew, members of the ground crew had to find a way to provide good air (among other things) for the astronauts as they returned home.

This photo, of Apollo 13's crew in flight, depicts their efforts to create a workable solution.  NASA provides a description of the image:

Interior view of the Apollo 13 Lunar Module (LM) during the trouble-plagued journey back to Earth. This photograph shows some of the temporary hose connections and apparatus which were necessary when the three astronauts moved form the Command Module to use the LM as a 'lifeboat'.

Astronaut John L. Swigert Jr., command module pilot, is on the right. On the left, an astronaut holds in his right hand the feed water bag from the Portable Life Support System (PLSS). It is connected to a hose (in center) from the Lunar Topographic (Hycon) camera.

In the background is the 'mail box', a jerry-rigged arrangement which the Apollo 13 astronauts built to use the Command Module lithium hydroxide canisters to purge carbon dioxide from the Lunar Module. Lithium hydroxide is used to scrub CO2 from the spacecraft's atmosphere.

Since there was a limited amount of lithium hydroxide in the LM, this arrangement was rigged up to utilize the canisters from the CM [command module]. The "mail box" was designed and tested on the ground at the Manned Spacecraft Center before it was suggested to the Apollo 13 crewmen.

Because of the explosion [noted as a rupture in other NASA documents] of one of the oxygen tanks in the Service Module, the three crewmen had to use the LM as a 'lifeboat'.

Click on the image for a better view.