Hoag served as a pilot in the Air Force for 28 years. As a
Major, he also taught test pilots. In 1964, he applied for the
U.S. Air Force Aerospace Research Pilot School (ARPS) and received orders to attend class 64-C, which commenced in August 1964 at
Edwards Air Force Base in California. The commandant at the time was
Chuck Yeager, and Hoag's twelve-member class included
Spence M. Armstrong,
Alfred Worden,
Stuart Roosa,
Henry Hartsfield, and
Charles Duke. Hoag finished top of the class in September 1965. He joined the HL-10 program in 1969 as one of 4 pilots, including
John A. Manke,
William H. Dana, and
Jerauld R. Gentry. The HL-10 was one of five heavyweight lifting-body designs flown at
NASA's Flight Research Center (FRC) to develop safe maneuvering and landing of a low lift-over-drag vehicle designed for reentry from space. He completed his first glide flight on June 6, 1969, and made a total of 8 flights in the HL-10. Hoag holds the record for fastest lifting body flight, which reached Mach 1.861 on February 18, 1970. He also flew the
XB-70 Valkyrie. On June 8, 1966, Hoag was piloting a
Northrop T-38 Talon chase plane when the second prototype of the XB-70 collided mid-air with a
NASA/Lockheed F-104 Starfighter over
Barstow, California. The F-104 pilot
Joseph A. Walker and XB-70 co-pilot Carl S. Cross were killed, although the XB-70 pilot
Alvin S. White survived after
ejecting. The crash occurred when the XB-70's powerful
wake vortex flipped the F-104, causing it to strike the XB-70 tail and explode, while the XB-70 entered an uncontrolled spin and crashed. After retiring from the service, he worked at
McDonnell Douglas for a decade. He died in
Provo, Utah in 2024, aged 87. == Personal life ==