The following essay was written by Tom Drennan.
Some will tell you the R-2800 was built for the Corsair program, since without the demand for a super engine to meet the Navy's four first requirements for a new fighter (speed, speed, speed, and speed) Pratt & Whitney would not have been willing to spend the resources on development. Others will tell you Vought would not have considered trying to build a 400 M.P.H. fighter without an engine like the R-2800 coming along nicely. The truth is even stranger. Propeller development had caught up with and past engine development. Both Curtis and Hamilton had learned to build propellers that could make good use of 1000 horsepower and more. Realizing the propeller no longer restricted the useable horsepower an engine could deliver, everybody began to ask for the "ton" engine as they dreamed of a new breed of fighters that could exceed four hundred miles per hour in level flight. P&W answered with the R-2800, and Wright with the R-3350.
There were considerable differences in Army and Navy aircraft engines at the beginning of WW 2.The Army wanted to use truck parts where they could on airplanes, especially for plumbing and wiring. The Navy wanted to use higher quality plumbing common to their ships, and wiring similar to ships. The Army wanted to use turbo superchargers instead of engine driven blowers. General Arnold felt round engines belonged on bombers and transport airplanes, not on fighters. Fighters were supposed to have V-12 liquid cooled engines for sharper noses. The Navy did not want any liquid cooled aircraft engines at all. The Army ordered hundreds of Martin B-26s off the drawing board, some suggest to get their way in designing the engine. The Navy did not want turbo chargers; they had taken note of Rolls-Royce's success with the two speed engine-driven blowers. As a result engines, built for the Army and Navy were quite different. Besides tubing and electrical connections the Navy engine had a larger blower section, making it longer.
From the beginning the Corsair was designed for the Hamilton Hydromatic constant speed propeller. The Army seemed to favor the Curtis Electric constant speed propeller, but used both. The nose section and propeller shaft is different for each propeller. Needless to say these, differences hindered rapid design, refinement, and mass production. It also resulted in many model numbers to keep us confused.
One of the early major problems was moisture condensing in the mags, sometimes causing engine failure at altitude. Once befuddled engineers discovered the cause, a few feet of tubing to pressurize the mags solved that problem, but there were more.
When the Corsair was new, it had enough airframe problems to warrant major redesign before going into mass production, but the engine had its share of teething problems as well. Together they kept the Corsair out of the war for three years after the first flight of the XF4U.
The Corsair was not born a hairy-chested warrior; like most newborns it had to grow up to the job it was intended for. It was unusual for a new engine and air frame to be developed as one project. Normally a new engine was developed on a proven airframe, then an airplane was designed to take advantages of all its best points. New airframes were thus tried with proven engines. The Hellcat is a good example -- the XF6F first flew with a Wright R-2600 to get the airframe right, then the P&W R-2800 went on. Once they learned more about the R-2800, the F8F Bearcat was built to take full advantage of the engine. Leapfrog development of engines and airframes eliminated a fair share of teething problems with one or the other.
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