He developed his interest in flying at an early age; as a young boy, his first flight on fabricated canvas wings was aborted when his mother stopped him as he tried to launch off the branch of a tree in his yard.
Mantz applied for admission to the United States Army flight school at March Field, California but was told he needed at least two years of college to be eligible.
[3] In 1927, shortly before his graduation at March Field, Mantz was flying solo over the Coachella Valley when he spotted a train heading west over the empty desert floor up the long grade from Indio.
[3] This sort of dangerous stunt was fairly common during the early era of loosely regulated flying in the 1920s, but the train's passengers included ranking officers coming to March Field to participate in the graduation ceremonies and Mantz was subsequently dismissed from the army.
After working briefly in commercial aviation, Mantz went to Hollywood, attracted by the large sums of money movie stunt pilots were making at the time.
In an effort to gain notoriety, on July 6, 1930, Mantz set a record in flying 46 consecutive outside loops as a part of the dedication ceremonies of the San Mateo airport.
After much difficulty finding steady stunt work, he accepted a particularly risky assignment, flying a Curtis-Wright CW-16K through a hangar with less than five feet of clearance off each wingtip for the 1932 film Air Mail.
Air Mail was a hit and as word spread about his success in getting through the hangar unscathed, Mantz found more work and his professional ideas about stunt flying were gradually accepted by the studios.
One of his helicopters appears in the Errol Flynn short documentary film, Cruise of the Zaca (1952), as featured on the 2 disc Special Edition DVD of The Adventures of Robin Hood.
During this period, Mantz carried out a number of "mercy" flights including transporting a deep sea diver to the Mare Island Navy Yard where a decompression chamber was able to save his life, flying 15 Mexican fishermen to safety after their boat began to break up, and dropping supplies to assist 53 trapped firefighters in the Santa Barbara mountains.
On July 4, 1938, Mantz flew from Wichita to Burbank, California, accompanied by Paramount press agent, pilot, and pulp writer, Edward Churchill, in an attempt to break the speed-dash record.
When they reached Burbank, the landing gear jammed and it took 30 minutes to work it loose, while thousands of spectators looked from the ground and the fuel ran perilously low.
During World War II, Mantz enlisted and was commissioned a major (later promoted to lieutenant colonel), serving in the First Motion Picture Unit (FMPU) in California.
With his longtime mechanic, Cort Johnson, he totally rebuilt the P-51C, stripping out all military issue equipment and modifying the wings with "wet" fuel cells.
Mantz used his B-25 to film Cinerama sequences of military aircraft at Eglin Air Force Base, Florida, in October and November 1956, for the Lowell Thomas production, Search for Paradise, released in 1957.
[23] In 1959, an investigation by the Civil Aeronautics Board, the now defunct US Federal agency that, at the time, tightly regulated almost all US commercial air transportation, allowed the airline to keep its operating authority, notwithstanding an initial judgment by the CAB examiner that it should not.
Flying a very unusual aircraft, the Tallmantz Phoenix P-1 built especially for the film, Mantz struck a small hillock while skimming over a desert site in the Algodones Sand Dunes for a second take.
Toxicology tests were performed several hours after the accident; in the absence of refrigeration, normal postmortem biochemical processes might produce blood ethanol and cause or contribute to an elevated BAC level.