A buckle that connects the pilot to the parachute is being blamed for a fatal Snowbirds crash earlier this year in Montana.

The Directorate of Flight Safety has released its initial report into the crash that killed Captain Shawn McCaughey and says the pilot's seatbelt unbuckled during an inverted pass.

Director of DFS Colonel Chris Shelly says the lap belt connector that is suspected to have caused the incident was replaced on the Snowbirds' Tutor jets immediately following this spring's crash.

He also adds in 2002 a similar incident happened with the same type of seatbelt, but the pilion was able to recover the aircraft.