Apollo 13

Apollo 13 was the seventh manned mission in the American Apollo space program and the third intended to land on the Moon. The craft was launched on April 11, 1970, at 13:13 CST. The landing was aborted after an oxygen tank exploded two days later, crippling the service module upon which the Command Module depended. Despite great hardship caused by limited power, loss of cabin heat, shortage of potable water and the critical need to jury-rig the carbon dioxide removal system, the crew returned safely to Earth on April 17.
The flight was commanded by James A. Lovell with John L. "Jack" Swigert as Command Module pilot and Fred W. Haise as Lunar Module pilot. Swigert was a late replacement for the original CM pilot Ken Mattingly, who was grounded by the flight surgeon after exposure to German measles.

Objective
The Apollo 13 mission was to explore the Fra Mauro formation, or Fra Mauro highlands, named after the 80-kilometer-diameter Fra Mauro crater located within it. It is a widespread, hilly geological (or selenological) area thought to be composed of ejecta from the impact that formed Mare Imbrium.
The next Apollo mission, Apollo 14, eventually made a successful flight to Fra Mauro.

Oxygen tank incident

Explosion

"Houston, we've had a problem."

Swigert and Lovell reporting the incident on April 14, 1970
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En route to the Moon, approximately 200,000 miles (320,000 km) from Earth, Mission Control asked the crew to turn on the hydrogen and oxygen tank stirring fans, which were designed to destratify the cryogenic contents and increase the accuracy of their quantity readings. Approximately 93 seconds later the astronauts heard a loud "bang", accompanied by fluctuations in electrical power and firing of the attitude control thrusters.[6] The crew initially thought that a meteoroid might have struck the Lunar Module (LM).
In fact, the number 2 oxygen tank, one of two in the Service Module (SM), had exploded.[10] Damaged Teflon insulation on the wires to the stirring fan inside oxygen tank 2 allowed the wires to short-circuit and ignite this insulation. The resulting fire rapidly increased pressure beyond its 1,000 pounds per square inch (6.9 MPa) limit and the tank dome failed, filling the fuel cell bay (Sector 4) with rapidly expanding gaseous oxygen and combustion products. It is also possible some combustion occurred of the Mylar/Kapton thermal insulation material used to line the oxygen shelf compartment in this bay.[11]


Apollo 13's damaged Service Module, as photographed from the Command Module after being jettisoned
The resulting pressure inside the compartment popped the bolts attaching the Sector 4 outer aluminum skin panel, which as it blew off probably caused minor damage to the nearby high-gain S-band antenna used for translunar communications. Communications and telemetry to Earth were lost for 1.8 seconds, until the system automatically corrected by switching the antenna from narrow-band to wide-band mode.
Mechanical shock forced the oxygen valves closed on the number 1 and number 3 fuel cells, which left them operating for only about three minutes on the oxygen in the feed lines. The shock also either partially ruptured a line from the number 1 oxygen tank, or caused its check or relief valve to leak, causing its contents to leak out into space over the next 130 minutes, entirely depleting the SM's oxygen supply.[11]
Because the fuel cells combined hydrogen and oxygen to generate electricity and water, the remaining fuel cell number 2 finally shut down and left the Command Module (CM) on limited-duration battery power. The crew was forced to shut down the CM completely and to use the LM as a "lifeboat".[12] This had been suggested during an earlier training simulation but had not been considered a likely scenario.[13] Without the LM, the accident would certainly have been fatal [14].