Before joining NASA in 1966, Swigert was a civilian test pilot and fighter pilot in the Air National Guard. After leaving NASA, he was elected to Congress from Colorado's new 6th district, but died before being sworn in.
John Leonard Swigert Jr. was born on August 30, 1931 in Denver, Colorado to parents John Leonard Sr. and Virginia Swigert. Swigert's father was an ophthalmologist. At the age of 14, he became fascinated by aviation. While he would have been content just watching planes take off from nearby Combs Field, young Jack became determined to do more than be a spectator. He took on a newspaper route to earn money for flying lessons, and by age 16 he was a licensed private pilot. He attended Blessed Sacrament School, Regis Jesuit High School, and East High School, from which he graduated in 1949.
Swigert received a Bachelor of Science degree in Mechanical Engineering from the University of Colorado in 1953, where he also played football for the Buffaloes. He later earned a Master of Science degree in Aerospace Engineering from the Rensselaer Polytechnic Institute (Hartford campus) in 1965, and a Master of Business Administration degree from the University of Hartford in 1967; and was presented an Honorary Doctorate of Science degree from American International College in 1970, and an Honorary Doctorate of Laws degree from Western State University in 1970, and an Honorary Doctorate of Science from Western Michigan University in 1970.
Following his graduation from Colorado in 1953, Swigert joined the U.S. Air Force. Upon graduation from the Pilot Training Program and Gunnery School at Nellis Air Force Base, Nevada, he was assigned as a fighter pilot in Japan and Korea. In 1953, he survived his plane crashing into a radar unit on a Korean airstrip.
After completing his tour of active duty in the Air Force, he served as a jet fighter pilot with the Massachusetts (1957–1960) and Connecticut Air National Guard (1960–1965). Swigert held a position as engineering test pilot for North American Aviation before joining NASA. He was previously an engineering test pilot for Pratt & Whitney, from 1957 to 1964. He logged over 7,200 hours in flight, with more than 5,725 in jet aircraft.