The PBY Catalina (also known as the Black Cat, Dumbo or P-Boat) is a flying boat mostly used by the US Navy in the Pacific Theater of World War II. However, they were used in every theater, by US, British and Soviet forces. It is the most diverse aircraft used in the war, as it was capable of being applied in conventional bombing, torpedo bombing, mine laying, depth charging, reconnaissance, rescue, or cargo transport and could land on the water or a runway. The PBY is credited as the most successful flying boat in WWII and consequently was the most produced, with 3,000 in service.
It has a wingspan of 104 ft. (32 m), is 64 ft. (20 m) long and 19 ft. (6 m) high. Its top speed is 180 mph (290 k/h), however it rarely gets much over 100 mph (160 k/h), and has a maximum range of 2500 miles (4100 km). It has two 1200 horsepower prop engines, two .30 cal. and two .50 cal. machine guns, and can be loaded with 4,000 lbs. of bombs or two torpedoes. Its crew consisted of seven to nine men: two pilots, a navigator, a radar operator, an aviation radioman, a flight engineer mechanic and three gunners.
The PBY Catalina is large and slow, making it an easy target for fighters or anti-aircraft batteries. Because of this, PBYs were painted in such a way that they would blend in to their surroundings, usually all blue or all black (hence the nick name Black Cat). Their large size was ideal for troop transport / rescue as well as cargo transport. Not to mention that the PBY could take a great number of hits to its fuselage and without any crewmembers being struck and its ably to fly still intact. The PBY's long range made it perfect for patrols and search and rescue. As long as they spotted before being spotted they had the advantage they needed. Their relatively quite engines allowed them to "sneak up" on enemy ships at night and cause some damage, perhaps even sink them, before radioing in their position and flying off into the darkness.
The Battle of Midway, the largest naval battle ever and the turning point in the war in the Pacific, is a great example of how these crafts performed under pressure. Early morning of the first day, a PBY search group found part of the Japanese invasion force steaming for Midway. Later that morning one struck the first hit of the battle, torpedoing a tanker (some reports say it was a troop transport). As a result of this attack, one of these PBYs became the first American casualty of the battle, being shot down by a Japanese seaplane. After finding these transports, 22 PBYs were launched to search for the Japanese carriers. An hour later they spotted the carriers with their bombers already in the air on their way to Midway. Over the next three days PBYs played as many roles as they were able, as the eyes of the Navy reporting burning ships and incoming air raids, as fighters, gunning down any aircraft they could, as torpedo bombers, and as saviors, picking up a number of downed pilots and sailors who had fallen into the sea.
After the war, PBYs were used by Navy to test jet assisted take-off (JATO) units. PBYs are still used today, 60 years later, as water bombers in fighting forest fires.
Sources:
http://www.pby.com/
http://www.history.navy.mil/faqs/faq81-1.htm
http://www.cv6.org/1942/midway/
http://www.daveswarbirds.com/blackcat/
My grandfather, a PBY pilot and Midway veteran