Bell
Model 30
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Photo: Robert Deering 10/23/2007
Smithsonian National Air and Space Museum
Chantilly, Virginia
The Model 30 represents the successful gamble by Bell Aircraft Corporation founder Lawrence Bell to enter the nascent helicopter market of the mid-1940s. While this aircraft was only a demonstration prototype, its production variant, the Model 47, has managed to remain in service in one form or another longer than any other helicopter type, and some are still operating at the start of the twenty-first century. A unique pool of talent, brought together by Lawrence Bell included the helicopter pioneer, Arthur Young, and a superb engineer, Bartram Kelly, was responsible for the success of the Model 30 and its descendents.

Arthur Young's career as a helicopter pioneer began with an intense intellectual compulsion to address the technical problems of the age. In the late 1920s, he realized that a stable, controllable helicopter was one of the few technological challenges of the time that had not shown signs of significant progress, and set about finding a solution. Young approached the development of a practical helicopter in a methodical and scientific manner that was not common practice among many of his fellow pioneers, who relied on trial and error, using full-scale aircraft. Instead, Young used inexpensive, and easily-constructed, remotely-controlled models to test the validity of his theories. This simple expedient allowed him to refine his designs rapidly, and to become recognized as a leader in solving the technical hurdles that had kept helicopter development stagnant for decades. By 1941, Young was flying 1/6-scale models that demonstrated levels of stability and control that were unprecedented in previous helicopter designs. He effectively incorporated Igor Sikorsky's tail rotor concept, at a time when most helicopter pioneers viewed it as impractical.

Young's most innovative design feature was to incorporate a stabilizer bar on the rotor mast perpendicular to the rotor blades. This counterbalance system caused the rotor to teeter when the airframe of the helicopter moved in response to turbulence, or control inputs, and dampened further oscillation. This feature allowed an unprecedented level of stability. Other designers were still using hinges to create rotor stability, but those designs relied on a significant lag time in rotor response, which Young had revealed in his experiments to be minimal.

Meanwhile, Lawrence Bell had come to the conclusion that, after the war ended, Americans would begin to rely on personal aircraft for personal and that the helicopter offered the most practical means to achieve it. He realized that the military contracts that had sustained his business thus far would dry up as soon as peace was declared, and that his company's only hope for continued survival was to find a product for which there would be a great deal of commercial demand. However, Bell had no experience with helicopter design and was looking for someone with a workable concept, when he was introduced to Arthur Young. Bell was immediately impressed with Young's latest flying model, and they quickly came to an agreement for construction of two full-scale aircraft. The first helicopter was to be a single-seat demonstration aircraft, followed by a two-seat version.

By June 1942 construction had begun on Young's first full-scale prototype, known as the Model 30 Ship 1. The rollout was a mere six months later. The airframe consisted of a steel tube structure with a specially manufactured magnesium tail boom. Rotor blades were made of a wooden laminate with a metal spar leading edge and balsa filler in the trailing edge. The 160 hp Franklin motor was mounted vertically, which was an improvement over earlier Sikorsky models that required additional weight-consuming gearing for their horizontally mounted engines. Landing gear initially consisted of four spider-like skids. Larry Bell wanted the flight controls to be more like those of an automobile than an airplane, thus the collective pitch lever moved side to side as a replacement for rudder pedals that were likely to be mishandled by novice private pilots who were used to automobile pedals. This feature was later abandoned when it became apparent that the configuration pioneered by Sikorsky would be the industry standard.

Shortly after Ship 1's first flight on December 29, 1942, the tail boom was destroyed in a crash. It was replaced by an open inverted triangular steel-tube truss that would later become a hallmark of the Model 47. The design team then traded the skid landing gear for a conventional tricycle undercarriage. The tail was destroyed for a second time in a September 1943 crash. At this point Ship 2 had been almost completed and took up the testing slack while Ship 1 was repaired. Upon completion of its repairs, a newly designated Ship 1A rolled out of the shop wearing a new magnesium-skin tail, as well as a strengthened rotor system and landing gear. Ship 1A flew in a series of public demonstrations designed to generate public enthusiasm for the new form of aerial transport, while Young and his workers completed a third Model 30 variant. Ship 3 was a three-seat no-frills version that took full advantage of the lessons learned on the two earlier models. On one occasion, this design flew with seven people on board, most of whom were hanging off the side. This demonstration dramatically the improvements that had been made over the Sikorsky R-4 and R-6 series that could barely lift two people.

By war's end, Bell was ready to begin production of a new design, designated the Model 42. This luxury sedan of the skies proved to be a dismal failure. While Young and Kelly were working on theoretical studies, Bell's production engineers, whose experience was limited to airplanes, worked on the design of the Model 42. Their inexperience resulted in an unreliable and under-powered aircraft that was priced well beyond the reach of most private citizens. The only hope for Bell's future in the helicopter industry was to put the Model 30 Ship 3 into production as a military and commercial utility helicopter. This decision resulted in the Model 47, which became the world's first commercially certified helicopter on March 8, 1946.

Ironically, the same military contracts that Larry Bell did not want to depend on in the post-war marketplace were the salvation of the company's financial success, and established it as a leading helicopter manufacturer. The superb Model 47 did not fare much better than the Model 42 when it first appeared, largely because the value of the helicopter to the business community had not been established by Bell and other manufacturers, who had instead focused their efforts on private users. As the military's Sikorsky R-6s began to wear out, a search began for a new liaison and light medevac helicopter. The Model 47 was chosen over the similar Hiller Model 360, and a short time later, established a sterling reputation as a flying ambulance in Korea. After the Model 47 gained notoriety in Korea and in demonstrations of industrial applications, the type became an outstanding success, with a total of 5,000 sold to military and commercial users.

After its useful days had ended, the Model 30 Ship 1 was donated to the Franklin Institute. In 1964, on the 20th Anniversary of the American Helicopter Society, it was given to the Smithsonian Institution along with the Piasecki PV-2. The stability and smooth handling of the Model 30 and its successors were qualities that were essential if the helicopter was to establish a niche in the civil market. The unique combination of Arthur Young's inventive genius and Bell's marketing skills created a product that quickly transformed an experimental category of aircraft into a safe, and reliable machine with unprecedented utility. After the creation of the Model 30, helicopter development was not left to individual dreamers, but was embraced by many of the giants in the aviation industry as an essential element in maintaining their position in the aviation industry.

SPECIFICATIONS:

Rotor Diameter 9.98 m (32 ft 9 in)
Length 8.19 m (26 ft 10.5 in)
Height 2.62 m (8 ft 7 in)
Weight Empty, 521.6 kg (1150 lb)

Source: Smithsonian National Air and Space Museum