Colonel Christensen served twenty-two years in the Air Force. He enlisted in 1951 at the beginning of the Korean War, but did not arrive in Korea until hostilities had ended. Over the years he accumulated over 4400 hours in jet fighter aircraft, including the F-84G, F-84F, F-100F, F-101A, F-101B, and the F-4C and D. He flew 201 combat missions in the Vietnam Conflict, 35 of them over North Vietnam and earned two Distinguished Flying Crosses and fourteen Air Medals, as well as numerous other decorations, retiring as a Lieutenant Colonel.