A front-wheel mechanical failure as her jet car approached 550 mph apparently caused the August crash that killed speed racer Jessi Combs, according to the Harney County Sheriff’s Office.

The failure occurred Aug. 27 as the car, powered by a jet engine, sped across the Alvord Desert in southeast Oregon, according to a news release from the sheriff’s office. Combs, 36, was attempting to break the women’s land speed record of 512 mph set in 1976 by Kitty O’Neil.

Based on evidence collected at the scene and recovered by her North American Eagle Racing Team, the failure was most likely caused by hitting an object in the desert about 180 miles southeast of Bend, according to the news release dated Sept. 17. The failure led to the collapse of the front wheel.

Combs died from blunt force trauma to the head that occurred before a fire engulfed the race vehicle after the crash, the news release stated.

Widely known in the niche sport of jet-car racing, Combs holds the record as the fastest woman on four wheels — O’Neil piloted a three-wheeled vehicle — for a 398 mph performance in 2013 and had driven even faster in follow-up runs, but mechanical problems prevented those from making the record books. She was known by fans as the “fastest woman on four wheels.”

Combs was born in Rapid City, South Dakota, and lived in Long Beach, California. She turned down a full scholarship to interior design school to travel North America, settling in Denver to start a snowboarding career, according to her website. She studied collision/refinishing, chassis fabrication, street rod fabrication and trim/upholstery at WyoTech, graduating at the top of her class. Combs also took up metal working, leather craft and photography, her website stated.

With her education in automotive design and fabrication, she appeared as a host on Spike TV’s “Xtreme 4X4” before a freak accident with a piece of heavy machinery broke her spine.

After months of rehabilitation, Combs recovered and appeared on and guest hosted a number of other shows, including Discovery Channel’s “Mythbusters,” while honing her skills as a professional driver for movies and commercials.