A known problem with the lap belt design on Snowbird jets was the cause of a pilot losing control and crashing during a practice run in 2007, a report released Monday concludes.
The crash occurred during an afternoon practice on May 18 involving four Snowbird Jets. The group was preparing for a weekend show at the Malmstrom Air Force Base open house in Montana.
Capt. Shawn McCaughey, 31, died when he lost control of his plane and crashed into the ground without ejecting.
The report, from the Flight Safety Directorate of the Canadian Air Force, concludes that his lap belt did not engage properly, which led to McCaughey falling out of his seat during an upside-down manoeuvre.
According to the report, a piece of equipment obstructed the plane's control stick, preventing the pilot from raising the nose of the aircraft.
The report said that the use of the ejection seat system was "not a viable survival option," and the pilot did not attempt to eject.
The report notes that the lap belt problem was a known issue for the planes, in which the belt sometimes appeared to be correctly fastened when it was not.
The report adds that the so-called false-lock problem had been communicated to pilots, who were given procedures to follow to address the issue.
The report noted that McCaughey was familiar with the procedures and had employed them in the past, but the report could not say why the false-lock issue was not remedied before the 2007 crash.
"This tragic accident was clearly preventable," the report said. "There was a known airworthiness deficiency, and training was provided to the aircrew to mitigate the risk in the short term."
The report said pilots were supposed to follow certain procedures to ensure their lap belts were securely fastened, but that did not happen in this case.
"This accident also serves to highlight dangers of complacency," the report concluded.
It noted that about five years had passed between the initial observation of a problem and McCaughey's crash.