Walter W. 'Penny' Pentecost's involvement in the world of aviation spanned the greater part of his lifetime. Following a stint as a barnstormer in the 1920s, Pentecost studied engineering at Purdue University. While working at North American Aviation as an Allison engine specialist, he was hired by the Intercontinent Corporation as an 'advance man' for the American Volunteer Group (a.k.a. the Flying Tigers). He was stationed in Rangoon, Burma between May and November of 1941 to oversee the assembly of approximately 100 Flying Tiger Curtiss P-40 Warhawks that were shipped to that nation for the Flying Tigers' mission to defend the Burma Road. Following this mission, Pentecost was sent to Loiwing, China, where he became involved with locating and refurbishing downed combat aircraft, and rescuing reusable parts that could be used to reconstruct other airplanes. Upon his return to the United States, Pentecost worked as a flight test engineer for combat airplanes, and as a service engineer for the Nike Zeus missile system. He also spent time as a project engineer for the Manned Orbiting Laboratory and assisted with NASA's Sky Lab.