Four hundred members of the Canadian military were in Nunavut recently for a search-and-rescue exercise called “Operation Nanook.”

That’s when troops practice rescuing pretend air-crash victims just in case it ever happens.

The soldiers were to perform the exercise for Prime Minister Stephen Harper.

However, the mock exercise was cancelled when there was a real plane crash nearby. The team raced out to help the victims.

The soldiers knew it was real when someone said, “NODUF,” which is slang for “this is not a drill.”