Pilot Maj. Harry Schmidt, the so-called flight-lead, told investigators he thought the flashes were from surface-to-air missiles being fired at the jets.

Despite being denied permission to fire, Schmidt dropped his bomb on the Canadians anyway. Shortly before he fired, an AWACS surveillance aircraft alerted the pilot that "potential friendlies were in the area."

In such a scenario, U.S. procedure dictates a fighter pilot leave the area to assess the threat before opening fire. Neither Schmidt nor his wingman Maj. William Umbach did so and instead rushed to attack.