13 was intended to be the third mission to carry humans to the surface
of the Moon, but an explosion of one of the oxygen tanks and resulting
damage to other systems resulted in the mission being aborted before
the planned lunar landing could take place.
13 was launched on a Saturn V on 11 April 1970 from pad 39A at Kennedy
Space Center. During second stage boost the center engine of the
S-II stage cut off 132 seconds early, causing the remaining four
engines to burn 34 seconds longer than normal.
broadcast was made from Apollo 13 from 02:24 UT to 02:59 UT on 14
April and a few minutes later, at 03:06:18 UT Jack Swigert turned
the fans on to stir oxygen tanks 1 and 2 in the service module.
The Accident Review Board concluded that wires which had been damaged
during pre-flight testing in oxygen tank no. 2 shorted and the teflon
insulation caught fire. The fire spread within the tank, raising
the pressure until at 3:07:53 UT on 14 April (10:07:53 EST 13 April;
55:54:53 mission elapsed time) oxygen tank no. 2 exploded, damaging
oxygen tank no. 1 and the interior of the service module and blowing
off the bay no. 4 cover.
the oxygen stores depleted, the command module was unusable, the
mission had to be aborted, and the crew transferred to the lunar
module and powered down the command module.
conserve power and other consumables the lunar module was powered
down except for environmental control, communications, and telemetry,
and passive thermal control was established.
service module, which had been kept attached to the command module
to protect the heat shield, was jettisoned and the crew took photographs
of the damage. The command module was powered up and lunar module
was jettisoned. Any parts of the lunar module which survived atmospheric
re-entry, including the SNAP-27 generator, planned to power the
ALSEP apparatus on the lunar surface and containing 3.9 kg of plutonium,
fell into the Pacific Ocean northeast of New Zealand. Apollo 13
splashed down in the Pacific Ocean on 17 April 1970 at 18:07:41