RENO, Nev. (AP) - Federal safety regulators are focusing on loose screws in the tail of World War II-era fighter plane modified to race faster than 500 mph as a likely cause of the crash that killed the pilot and 10 others during air races in Nevada last year.
The National Transportation Safety Board released nearly 1,000 pages of documents and photographs Tuesday as it investigates the cause of the September 2011 crash at the Reno Air Races.
Regulators also point to potential deficiencies in inspection procedures.
The board says inspectors noted screws used earlier were too short in one of the trim tabs that help control the aircraft. The crew reportedly fixed the problem and the plane was cleared to race.
The NTSB says there was "no written procedure or sign off to ensure" that was the case.
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