Authorities have revealed that wheel failure it was caused the fatal crash that killed 'Mythbusters' star Jessi Combs in late August. 

"Based on the evidence collected and examined at the scene of the crash and the evidence recovered by the North American Race Team it appears that there was a mechanical failure of the front wheel, most likely caused from striking an object on the desert," a release from the Harney County Sheriff's Office obtained by USA Today read. "The front wheel failure led to the front wheel assembly collapsing. The front wheel failure occurred at speeds approaching 550 miles per hour."

Combs died while attempting to break a land-speed record in a desert in southern Oregon and was attempting to reach speeds of 512 MPH. She died from blunt force trauma to the head. 

Combs was known as the "fastest woman on four wheels" and had appeared on the television shows Xtreme 4x4 and Overhaulin in addition to Mythbusters.