Apollo 13 was a NASA lunar landing mission, specifically designed to explore the Fra Mauro formation (Fra Mauro highlands). It launched from the Kennedy Space Center in Florida at 13:13 CST on April 11th 1970. The mission was aborted approximately 56 hours in due to a malfunction that seriously compromized the crew’s power and oxygen.

The Apollo 13 crew consisted of:

• James A. Lovell, Jr – commander
• John L. Swigert, Jr – Command Module pilot
• Fred W. Haise, Jr – Lunar Module pilot

Astronaut Ken Mattingly (Thomas K. Mattingly II) was originally intended to fly the Command Module. Shortly before the mission, Mattingly was exposed to German measles, for which he had no immunity. It was simply too risky to allow him to fly, and so Swigert, the Command Module pilot of the backup crew, was called in to replace him 3 days before the launch.

Apollo 13 was made up of the Aquarius (the Lunar Module or LM), and the Odyssey (the Command and Service Module or CSM/CM/SM). On April 14th, one of the SM’s oxygen tanks exploded, and the resulting ruptured tank began to lose oxygen, leading to subsequent loss of other essentials, including water and electrical power.

The CSM was immediately powered down to save batteries for re-entry into Earth’s atmosphere, and the crew then powered up the LM in order to stay alive. The narrow LM was designed for a lunar landing, i.e. to support 2 people for around 2 days, not 3 people for several days. Its use for survival and propulsion in space was uncharted territory.

In order to point in the direction of Earth, the crew had to use the Moon’s gravity to effectively turn the craft around, before burning the LM descent engine to adjust their trajectory. Using the SM’s engine for a direct abort was too dangerous as the full extent of the damage to the SM was unknown. The LM’s engine proved proficient for making several course corrections.

On their return to Earth, the crew were increasingly uncomfortable, partly due to the lack of heat. The build-up of carbon-dioxide was particularly concerning as the scrubbers in the LM ran out, and CSM scrubbers were different. Mission Control in Houston had to guide the crew in assembling an adaptor using materials available in the craft. This was among many tasks simulated by teams on Earth to assist in the crew’s safe return.

Apollo 13 powered up the CM’s essential systems as per Mission Control’s guidance and jettisoned the SM and LM shortly before re-entry to Earth on April 17th. Fortunately, the heat shield and parachutes had not been damaged. Splashdown occurred at 18:07:41 UT in the South Pacific, where the astronauts were safely retrieved from the craft. An extensive investigation of the accident determined that a combination of poor design and oversights were likely responsible for the malfunctions.

For a more detailed account of the Apollo 13 mission, including information on the cause of the accident, visit NASA’s Apollo 13 website and/or the Apollo 13 entry in the Encyclopedia Astronautica. For booklovers, there is Jim Lovell and Jeffrey Kluger’s “Lost Moon: The Perilous Voyage of Apollo 13”, published by Houghton Miffli in 1994.

Sources

The Apollo 13 Accident (Apollo 13 Home Page), NASA Goddard Space Flight Center website, accessed: 12th October 2008, author: Williams, D.R.

Apollo 13, Encyclopedia Astronautica website, accessed: 12th October 2008, author: Wade, M.

Apollo 13 Facts, National Air and Space Museum website, accessed 12th October 2008, no author specified.

Apollo 13 – Stranded, Destination Moon (pp 84-105), published by: Carlton Publishing Group in 2005, author: Pyle,R.