viernes, 20 de agosto de 2010

PBY CATALINA

Ray Wagner – Flight Classics publication 1972

Flying boats have become rare on the aviation scène today, but there is one flying boat remembered by every flyer. The PBY Catalina is the most widely-used flying boat ever built. Originally, the American idea of a flying boat grew out of the Navy's Curtiss boats of World War l; twin-engine biplanes with open cockpits and lots of struts. It was the PBY that replaced this style with its own streamlined monoplane look. The story may be begun in 1927, when the United States Navy decided to get a new patrol plane that would be built as a 100 foot span monoplane with an all-metal structure and a range long enough to fly directly to Panama, Alaska and Hawaii.



The Consolidated Aircraft Corporation of Buffalo, New York, forerunner of today's Convair Division of General Dynamics at San Diego got the contract on 28 February 1928. Company General Manager Rueben H. Fleet put Isaac Macklin Laddon in charge of the design, called the Consolidated Model 16 by the company and XPY-1 by the Navy. The big boat was made in Buffalo, but since the nearby river was frozen, had to be taken to the Anacostia Navy Yard near Washington, D.C. for the final assembly and flight test. First flown 22 January 1929 the XPY-1 had two 450 hp. R-1340-38 Pratt & Whitney Wasps between an all-metal hull with four open cockpits and the fabric-covered, metal-structure wing. Top speed was only 118 mph, but 1021 gallons of fuel offered a theoretical range of up to 2,600 miles. To the company's disappointment, however, Consolidated got no production contract. Instead, Glenn L. Martin, who had underbid Consolidated for the contract, received an order 29 June 1929 for nine P3M-1 boats built to the same specifications, along with an XP2M-1 prototype designed with three larger engines.

Consolidated did succeed in selling 14 of a 20-passenger version called the Commodore. They went into service on a New York to Buenos Aires run, and were taken over in 1930 by Pan American Airways. Meanwhile, Laddon tried to prepare a more advanced version of his patrol plane type. A third engine was installed on the XPY-1 in August 1929, mounted high above the wings, but this was an awkward expedient to add more power.



The first PBY's



Success in building the P2Y patrol series led Consolidated to the design that became the principal Allied patrol plane of World War II. Isaac M Laddon designed the Consolidated Model 28 as an all-metal monoplane using two new Pratt & Whitney Twin Wasp engines, the 14-cylinder, twin-row, R-1830-58 giving 800 hp at sea level. Careful attention was given to streamlining, even to having the out-board floats fold upwards to become wing tips. The wings contained integral fuel tanks, and were metal, except for fabric covering aft of the rear spar. A prototype, designated XP3Y-1, was ordered on 28 October 1933 for $268,476.00, built in Buffalo, shipped by rail to Anacostia, and was first flown by company test pilot William B. Wheatley on 21 March 1935. The aircraft handled well, and was flown to Norfolk, Virginia on 28 March for further tests, although the original rudder had to be enlarged by extending the trailing edge. Competing with the XP3Y-1 was a Douglas flying boat, the XP3D-1 under test in California since 6 February. In Fleet Admiral E. J. King's memoirs, the former Bureau of Aeronautics chief remarked that these aircraft, "proved so similar in performance that the choice finally came down to a matter of price," and Douglas estimated $110,000 per plane. Consolidated got the contract on 29 June 1935, for 60 P3Y-1's at $90,000 each, plus 20 percent spare parts, drawings, tests, etc., for a total of $6,506,000. The designation was changed to PBY-1 in August 1936. In October, the public first learned of the plane's potential when LCDR Knefler McCinnis flew the XP3Y-1 from Norfolk to San Francisco, arriving 15 October 1935. This flight established a new seaplane world's record; an airline distance of 3,281 statute miles, and a broken line distance of 3,433 miles. The aircraft would have gone as far as Seattle, but had been unable to take on a full fuel load at Coco Solo; when fully loaded the rudder dipped into the water during takeoff. This fault was corrected on production ships by extending the hull below the rudder.



The XP3Y-1 came down to San Diego by 20 October 1935, when Consolidated's new factory was dedicated. Major Reuben Fleet had chosen the new site at Lindbergh field to utilize the climatic advantages. While the factory tooled up for production, the prototype was modified and flew again on 21 May 1936 with a new designation, XPBY-1. It’s configuration now included the rotating nose turret, modified tail, and new Pratt & Whitney R-1830-64 Wasps giving 850 hp at 8,000 feet and 900 hp for takeoff.



Top speed, originally 169 mph at sea level, was now increased to 184 mph at 8,000 feet. The improvement was desirable, because Douglas had also modified its prototype into the XP3D-2, with the same R-1830-64 engines and retractable floats. But the XPBY-1 was superior, and on 25 July 1936, the Navy placed a new contract for 50 PBY-2 aircraft at $4,898,000. In September 1936, the first production PBY-1 was accepted, and on 5 October, VP-11 became the first patrol squadron to receive one. The PBY-1 contract was completed in June 1937, and the first PBY-2 had been accepted in May. The remainder were accepted from September 1937 to February 1938.



Only minor changes distinguished the PBY-2. For ice shields, reinforcement plates were added to the hull parallel with the props, and a cut out in the rudder for the horizontal stabilizer instead of a cut out in the horizontal surface for a solid rudder. In service, the PBY's were immediate successes, making several flights in full squadron force. For example, VP-3 flew a dozen PBY-1's non-stop from San Diego to Coco Solo, 3,292 miles in 28 hours on 21 June 1937.



The first PBY released for non Navy use was the "Guba" for explorer Dr. Richard Archbold. registered NC 777, the "Cuba" was begun on 18 January 1937, and completed in June like a PBY-1 except for omission of military equipment. Archbold used it to make the first transcontinental flight by a flying boat. When the Russian crew of Levanensky disappeared on a flight across the North Pole, the first "Cuba" was sold to the USSR in August 1937, and flown by Sir Hubert Wilkins from Aklavik, Canada over the Arctic seas, searching in vain for the lost crew. During this period, the "Guba" was marked URSS L-2, and returned to New York, where it was disassembled and put aboard ship for Russia



A second "Cuba" was built for the explorer and made a shake-down flight to Miami on 3 December 1937. It retained the NC 777 registration, but can be distinguished from its predecessor by reinforcements on the hull outside the cockpit; shields to protect from propeller-flung ice. This "Cuba" left for New Guinea on 2 June 1938, spent eleven months exploring the area, and made the first flight around the world at its greatest diameter. It was sold to Britain in October 1940 and, registered C-ACBJ, provided BOAC transport service to West Africa. Both "Gubas" cost $378,286.00 with spares. The Soviet Union purchased three Model 28-2 cargo-mail boats, along with a license to build them in Russia. One boat was delivered complete, and the other two in sub-assemblies or parts for completion there. The first was begun on 29 March 1937, completed in December 1937, and the price included $623,015 for the aircraft, spares, and license, and $1,141,403 for tools. A party of 18 company engineers were sent in 1938 to help set up the factory in Taganrog, on the Sea of Azov. The plant turned out Soviet PBY's (GST) before being overrun by the Germans in October 1941.



The distinctive feature of the PBY's for Russia was their power plant Wright R-1820-G3 Cyclones rated at 840 hp at 8,700 feet. These were the only PBY's not using twin-row Pratt & Whitney engines. Single-row Cyclones were probably the Soviet choice because this engine was already in Russian production as the M-62. While the bow turret on the first PBY for Russia was replaced by a cargo hatch, the Soviet-built versions had a front gun turret of their own design, and enclosed cold-weather cowls. Later the 950 hp M-87 was used, and claimed to raise top speed to 204 mph. On 27 November 1936, 66 PBY-3s had been ordered and the first accepted in November 1937 had 1,000 hp R-1830-66 Wasps. The remainder were delivered from March to August 1938. Thirty-three PBY-4s were ordered 18 December 1937, and the first was accepted in May 1938 with R-1830-72 Wasps yielding 1,050 hp for takeoff, and 900 hp at 12,000 feet, bringing top speed to 297 mph there, or 176 mph at sea level. From October 1938 to June 1939, 31 PBY-4s were accepted, leaving delivery of the last deferred for special modification. Three of them (Bu Nos. 1241, 1242, and 1243) were fitted with new enclosures over the waist gunner's positions and a straight rudder trailing edge. A single example of the Standard PBY-4 was built, designated Consolidated 28-5, for the Royal Air Force. Registered P9630, and powered by the R-1830-S1C3C, it made the first flight delivery of a military aircraft across the Atlantic Ocean, in July 1939. A commercial version, the 28-4 for American Export Airlines route survey work, was also completed in June 1939, registered NC 18997, at a cost of $163,189.80. Weighing 15,896 Ib empty and 18,676 Ib gross, it was taken in 1944 for cargo work by the Navy, and numbered 99080.



On 20 December 1939, the Navy ordered 200 Consolidated PBY-5s, the largest single Navy air-craft since World War l. Contracts with Britain, France, Australia and Canada were made for 174 similar 28-5M's in the same period. The French orders were absorbed by Britain, and a new assembly line was begun in San Diego. The PBY-5 was accepted in September 1940 with 1,200 hp (takeoff) R-1830-82 engines, the first to use 100 octane fuel. Armament included two .50 caliber guns in the waist blisters with 840 rounds and a .30 caliber gun in the bow and in the tunnel with 1,500 rounds. Weight on #2289 was 15,384 Ib empty, and 28,957 Ib with 1,570 gallons of fuel. The second PBY-5 (#2290) was delivered to the Coast Guard in October 1940, registered V189, and stationed in San Francisco. November deliveries were three PBY-5 and the first three Model 28-5ME boats for Britain, registered as AM 264, W 8405 and AM 265. The British called the PBY "Catalina," a name adopted by the U.S. Navy in October 1941.



The war’s end closed the New Orleans plant and Catalina production. At that point total production included 2160 examples from San Diego, 235 from New Orleans, 731 from Canada and 155 from Philadelphia a total of 3281. It is unclear how many were produced by the Soviets perhaps a 150 or so. Many Catalina’s were purchased by civilian companies after the war and flown in the commercial cargo business and as private passenger planes. Unique among many civil conversions of the PBY, was the Bird Innovator: the only 4-engined PBY. Fighting fires became the PBY one of its specialties. On of the Canadian companies called Field Aviation (Toronto) started modifying a fleet of Canso/PBYs as water-scooper. Today the water-bombing career of a PBY is over and only a handful are flying as Warbirds and Private airplanes.







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