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THE XR—4 DEMONSTRATES PRACTICAL SHIPBOARD OPERATIONS, MAY 1943
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THE R—4’S UNGAINLY (BUT FUNCTIONAL) ROTOR HEAD.
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The R–4 was the first helicopter to go into full-scale production and enter regular military service. The prototype XR–4 made its first flight on January 14, 1942, and quickly demonstrated that it could serve as an effective trainer and demonstrator for the widespread introduction of helicopters to military service. In May 1942, it flew 761 miles from Stratford, Connecticut, to Wright Field, Ohio, where it became the first helicopter to be accepted by the military. The Army Air Forces put the XR–4 through its paces with an eye toward combating the U-boat menace in the Atlantic where they could give convoying merchant vessels a modicum of air cover. Trials included dropping depth bombs, deploying hydro-phones, and landing on a ship’s deck.
By mid–1943, the XR–4 had established the type’s viability and three YR–4As, twenty-six YR–4Bs, and one hundred R–4Bs were being delivered or were about to enter production. The R–4 never had the opportunity to confront U-boats. Eighteen made it to the Burma and Pacific theaters where they rescued nearly 100 injured and wounded personnel between April 1944 and the war’s end, though the type’s primary use was as a trainer for improved types.
Early helicopter operations were undertaken only in daylight and fair weather, so the instrument panel did not incorporate any gyroscopic instruments. The useful load of the R–4 was marginal and a single passenger/student and a partial fuel load were about all the aircraft could lift in typical flight conditions. Radios, if installed at all, were mounted in the back of the cockpit and were unreachable in flight, which meant that frequencies had to be set correctly beforehand.
An unusual feature of the R–4 was that unlike later helicopter trainers, it had only one collective pitch lever and throttle, located between the seats (for mechanical simplicity). With helicopter control depending on constant cyclic inputs, right-handed pilots wanted to leave their left hand free for the collective lever as it required far less manipulation. This meant that students in the R–4 had to learn from the right seat rather than from the left as was traditional for an airplane pilot. As the R–4 was the primary helicopter trainer through World War II, the first generation of helicopter pilots in the United States and Great Britain adopted a right-seat convention for helicopter piloting—a tradition that has largely held to the present day.