As is sometimes the case in aviation, an aircraft begins its career playing one role, only to follow it by serving in an entirely different one. This characterizes the Consolidated PBY Catalina, which served a number of functions in both peacetime and wartime. During this blog, we'll follow the Catalina and the progression of roles it played during its service.
Development of the PBY (Patrol Bomber Consolidated) began in 1933 in order to fulfill a requirement for a long-range patrol bomber capable of attacking enemy supply ships in rear supply areas, disrupting the effectiveness of frontline troops. Conversely, the US Navy invested millions of dollars in developing long-range flying boats from which to supply our own forces in the event of a potential conflict in the Pacific Ocean, flying boats having the advantage of using the entire ocean for a runway, in theory. Prevailing naval doctrine in the 1930's and 1940's emphasized the use of flying boats in a variety of roles, unlike the special mission aircraft of today. Initially, the US Navy contracted with Consolidated, Douglas and Martin to build a prototype flying boat aircraft. Though the Navy had adopted the Martin P3M and Consolidated P2Y designs two years earlier, both planes were underpowered with both limited capacity and range. While the Douglas aircraft was a competitive design, the Navy decided to proceed with the Consolidated plane due to the cost estimate of only $90,000 per copy.
The XP3Y-1 or Consolidated Model 28 was designed around a parasol wing with external bracing struts, mounted on a pylon over the fuselage. The aerodynamics of the PBY were relatively clean in comparison to earlier planes with retractable wingtip stabilizing floats, a cantilever cruciform tail, instead of the earlier strut-braced twin tail, in addition to an all-metal stressed-skin of aluminum with the exception of the ailerons and trailing wing edges, which were covered of fabric. The XP3Y-1 first flew in March 1935, just prior to its transfer to the US Navy for a series of service trials. Later that year the XP3Y-1 was returned to Consolidated for additional upgrades to bring the plane to patrol bomber standards. The upgraded design first flew in May 1936 with a record non-stop flight of 3,443 miles. The basic PBY design underwent a series of improvements over the next three years-virtually all after the aircraft had entered service as to speed production of the plane. The most significant modifications to the PBY design came in the form of the PBN-1 Nomad, which incorporated a longer and sharpened bow, extended by two feet, as well as the tail, which was enlarged and featured a new shape. The Nomad also offered larger wings, permitting a 2,000 lb. increase in gross takeoff weight along with larger capacity fuel tanks, which increased the aircraft's range by 50 %. Other improvements included continuous-feed controllers on aircraft weapons systems with an improved electrical system and an auxiliary power unit. The PBY entered service powered by two R-1830-64 radial engines mounted on the wing's leading edges, serving up 900 hp. each.
While the PBY was originally designed as a flying boat, an amphibian model (PBY-5A) first flew in 1939. The 5A was equipped with tricycle landing gear with the main wheels retracting upwards in the fuselage sides. Though this added weight to the plane, decreasing its range, some 1,428 examples of the 3,300 PBYs built were amphibians. The PBY was also one of the first US aircraft to mount radar. Though initially a metric wave radar with arrays of dipole antennas on the wings, which were later followed by a centimetric radar unit in a fairing on top of the cockpit. The PBY armament consisted of either single or twin .30 caliber machine guns in the nose turret with a single .50 caliber machine gun in each waist blister along with a .30 caliber gun protruding from the hatch near the tail.
The PBY saw its first combat with the RAF Coastal Command in the Spring of 1941, in which one of the PBYs sent to Britain under the Lend Lease program discovered the battleship Bismarck in the North Atlantic, which led to its sinking by Royal Navy capital ships. The PBY was designated the Catalina by the British-a name which stuck with the aircraft for its entire career. When the United States entered the war in December 1941, the Catalina was deployed on a global basis. While initial missions for the Catalina in the Pacific were primarily long-range reconnaissance and a few anti-shipping strikes, the situation in the Atlantic was vastly different with the Catalina employed in an anti-submarine role against the U-boat threat. The range of the PBY, as well as its adaptability, gave it an advantage over a number of anti-submarine aircraft. The Catalina was one of the first aircraft to employ a Magnetic Anomaly Detection system in the tail boom. The MAD system could detect a submerged submarine provided the aircraft flew at low altitude coupled with the submarine cruising at a shallow depth. The Catalinas were also fitted with special retarding bomb racks, causing the bombs to fall vertical instead of traveling horizontally with the speed of the aircraft. Another advantage of the PBY was its wet wing design, in which the entire wing could act as a fuel tank, contributing to its long range. Though the PBY had a relatively low cruising speed, it was responsible for the sinking of 38 U-boats during the course of the war.
Catalinas distinguished themselves in the Pacific in a number of respects. The first United States aircraft to attack the Japanese was a Catalina that bombed a midget submarine an hour before the main assault on Pearl Harbor. The first US bombing raid of the Pacific war occurred four months before the Doolittle Raid, in which six PBYs were flown out of Ambon Island, in the Dutch East Indies, to bomb a Japanese base at Jolo, in the southwest Philippines. Catalinas were the only aircraft available at the time to conduct the mission, a 1,600 mile round trip. It was the efforts of PBY crews, flying overlapping patrols, which discovered the Japanese fleet approaching Midway in June 1942. A month later a PBY crew spotted a crashed Japanese Zero fighter on Akutan Island, just east of the Dutch Harbor naval base. The crashed Zero was involved in the diversionary attack on the Aleutians, during the Battle of Midway. The Zero was restored by USAAF personnel and test flown. This discovery enabled US fighter pilots to develop tactics which overcame the Zero's performance. Later in the war, air-sea rescue Catalinas, called Dumbos, retrieved thousands of ditched pilots and shipwrecked seamen, often under fire and stormy seas. One Australian Catalina is noted for picking up 87 Dutch sailors after their ship was attacked by Japanese planes. Catalina crews also carried out anti-shipping raids against Japanese barges and supply ships throughout the southwest Pacific. Called the Black Cats, due to their missions being flown at night in pitch black PBYs, the crews played a key role in disrupting the supply chain of Japanese forces. The Cats also raided Japanese bases and port facilities. Catalinas were also effective in mining harbors and were successful in tying up a number of strategic ports, including the major oil port of Balikpapan Borneo.
The PBY had a civil career as well as a military one. In the late 1930's several British and American airlines bought PBYs as survey aircraft. The Australian airline, Qantas, flew elite passengers from Perth to Ceylon between 1943 and 1945. Many of these flights were of 32 hrs. duration. After World War II, a number of Catalinas were converted into flying yachts during the era of restored warplanes for luxury purposes. Some were even flown into the 1990's as firefighting aircraft. Surplus PBYs were also used as deep sea fishing craft. While not a graceful nor a sleek aircraft, the Catalina proved to be a versatile design, serving a vital need at a difficult time. Perhaps its greatest tribute is it being in service long after similar aircraft have faded away.