Beg to differ
Quote from Wikipedia online Encyclopedia
"In World War II, PBYs were used as anti-submarine warfare aircraft, patrol bombers, convoy escorts, search and rescue aircraft, and transports. The Catalina can be considered the most successful aircraft of its kind, as no other flying boat was produced in greater numbers. The last active military Catalinas were not retired from service until the 1980s. Even today, over seventy years after its first flight, the aircraft continues to fly as an airtanker in aerial firefighting operations all over the world."