John Leonard Swigert Jr. (August 30, 1931 - December 27, 1982) was an American NASA astronaut, test pilot, mechanical engineer, aerospace engineer, United States Air Force pilot, and politician. In April 1970, as command module pilot of Apollo 13, he became one of twenty-four astronauts who flew to the Moon. Before joining NASA in 1966, Swigert was a civilian test pilot and fighter pilot in the Air National Guard. After leaving NASA, he ran for Senate but lost in a primary election against Bill Armstrong. Later he ran for Congress, but while running was diagnosed with cancer. He won the election for Colorado's new 6th district in 1982, but died before being sworn in.