Bayles flew the Gee Bee Model X in the Cirrus Derby in 1930, coming in second and sharing the $7000 purse with the Granvilles.
In 1931, Bayles piloted a Gee Bee Model E Sportster in the Ford National Reliability Air Tour, coming in fourth in the point standing and winning the Great Lakes Trophy for a total of $2000 in prize money.
[3] Bayles had failed to break the official 3 km World Landplane Speed Record at the 1931 National Air Races.
Following the Thompson Trophy race, the Gee Bee Z was re-engined with a larger, 750-horsepower (560 kW) Wasp Senior radial, in preparation for an attempt at establishing another world speed record at Wayne County Airport in Detroit, Michigan.
It struck the pilot and incapacitated him, causing a sudden upset in pitch that led to the structural failure of the wing.
[5] In addition, tests of a reproduction aircraft have shown that the Gee Bee Z was susceptible to aerodynamic flutter at high speed.