Santini was a veteran of World War II and the Korean War, serving as a combat aviator for the U.S. Army in both conflicts. During his wartime experiences, Santini became a good friend of fellow American military aviator Alan B. Hawke. After Hawke and his wife were killed in a boating accident, Santini raised the Hawkes' two young sons. After St John Hawke went missing in action during the Vietnam War, Santini and Stringfellow Hawke dedicated themselves to the operation of Santini Air, a Van Nuys, California-based air charter service founded and owned by Santini that specializes in performing aerial stunts for Hollywood film productions.