found: Wikipedia, 7 April 2011(the Consolidated PBY Catalina was an American flying boat of the 1930s and 1940s produced by Consolidated Aircraft; during World War II, PBYs were used in anti-submarine warfare, patrol bombing, convoy escorts, search and rescue missions, and cargo transport; the initialism of "P.B.Y." was determined in accordance with the U.S. Navy aircraft designation system of 1922, PB representing "Patrol Bomber" and Y being the code used for the aircraft's manufacturer, Consolidated Aircraft; Canadian-built PBYs were known as the Canso)
