Canadian divers have stumbled upon what they believe is the wreckage of a Maine-based U.S. Army air force amphibious plane that went down in the St. Lawrence River in 1942. The government divers announced Thursday that they came across the wreck while doing routine work in eastern Quebec. It has not yet been confirmed whether it is the lost plane. According to the War Department, which later became the U.S. Department of Defense, the plane had completed the first leg of a routine flight and was taking off for the return trip to base when it capsized in rough weather in the eastern Gulf of Saint Lawrence on Nov. 2, 1942. Nine people were aboard the PBY-5A Catalina, which was based at Presque Isle, Maine. Four crew members survived. But five were lost.