The claim at the time was this was not sexism or racially motivated sabotage. No, they claimed it was a commonality with barnstorming addressed by the Air Commerce Act of 1926 that mandated the regulation of pilots and aircraft. William Wills was also killed as a result of the wrench.

…to perform at shows where the crowd was segregated. “A woman is free if she lives by her own destiny. If she prizes her individuality and puts no boundaries on her hopes for tomorrow.” She died in a 1926 test crash. A wrench was found lodged in the engines control gears.