The Canadian destroyer HMCS Athabaskan was one of four Iroquois class anti-submarine destroyers that entered Canadian service in the early 1970s.

The photograph highlights one of the ship's main anti-submarine systems: the landing deck and hangar for two Sea King helicopters (centre). Thanks to the Canadian-developed "bear trap" system that allowed large helicopters like the Sea King to land on small warships, even in rough seas, Athabaskan and other helicopter-equipped Canadian ships could carry out anti-submarine warfare operations in virtually all types of weather, a critical military advantage.

George Metcalf Archival Collection
CWM 19910109-164