The major was overseeing ground crews who were in direct radio contact with the U.S. F-16 jets, officials told CBC News. His name has not been released.
Four Canadian soldiers were killed and eight others wounded during a training exercise just after midnight April 18.
Ottawa and Washington conducted separate inquiries into the tragedy, and concluded that the American pilots were wrong to drop the bomb.
Maj. Harry Schmidt and Maj. William Umbach have since been charged with involuntary manslaughter, assault and dereliction of duty. Each faces up to 64 years in prison.
FROM SEPT. 13, 2002: U.S. pilots charged in deaths of Canadian soldiers
The Canadian officer is not accused of any wrongdoing, and is expected to play a significant role as a witness during the two men's trial.
As part of a NATO exchange program, he had been assigned to a U.S. Airborne Warning and Control System (AWACS) squadron. He was mission crew commander when the Canadians were killed.
The major remains on active duty. He's coping with the deaths, but memories of that night will probably always haunt him, said his boss, Lt.-Col. Martin Galvin of Canadian Component of the 552nd Air Control Wing.
"Like the other members of his crew, both U.S. and Canadian, he was devastated when they found out the news," Galvin told CBC Sunday.
"He's handling it like the professional that he is," Galvin added. "He's bothered by it, of course, as we all are
I'm sure he'll have thoughts of it for his entire life."
Written by CBC News Online staff
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