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| Bell's
first helicopter was invented and built by Arthur
Young. The Model 30 had a 2-bladed rotor with
perpendicularly- mounted stabilizer bar. Without
the bar, movement of the rotor mast, mounted
directly to the rotors, would cause the plane of
rotation of the rotors to change, thus producing
instability. Centrifugal force of the stabilizer
bar, linked directly to the rotor, isolated the
rotor from the movement of the rotor mast which
was attached to the rotor hub by a universal
joint. Arthur Young's patent was later assigned
to Bell Aircraft Company. In November 1941, Young
joined Bell Aircraft and agreed to build 2
helicopters to demonstrate the concept. In
December 1942, the first of 3 prototypes, Ship 1,
was built at the Gardenville, NY plant. By July
1943, Ship 1 had reached speeds of over 70 mph.
Soon after, Ship 1 was damaged during a power-
off landing because of poorly designed landing
gear. It was rebuilt as Ship 1A with raised a
tail-rotor and modified landing gear to permit
the aircraft to remain in nose-up position for
power-off landings. Ship 2, a 2-passenger version
with enclosed cockpit, became the next test
vehicle. By 1944, the Model 30 was considered
ready for public display and was featured in a
Buffalo Sunday newspaper. In July of 1944, it
made it's public debut before a crowd inside
Buffalo Stadium. In early 1945, work began on Ship 3
designed with the best elements of Ships 1 and 2.
Four-wheel landing gear worked better on
take-offs and landings, different body shape with
the instrument panel in the middle and almost no
floor gave unobstructed vertical vision, and
later a bubble canopy gave undistorted vision. It
launched on April 20, 1945 and was an immediate
success. With room for 2 passengers, no
obstructive body or windshield, and only a small
instrument column between pilot and passenger,
the pilot had uninterrupted view up and down. The
Model 47, based on this design, made it's first
flight on December 8, 1945. On March 8, 1946, it received CAA Type
Certificate H-1 and was the first American
commercial helicopter. The Bell 47 has since been
produced by more countries than any other
helicopter in the world.
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| The first Bell
47s led to the pre-production military Model
47A and then came the commercial Model 47B.
Later came the 47B-3, 47D, 47D-1, 47E, 47G,
47G-2, 47G-3, 47G-4, 47G-5, 47H-1, 47J, and 47K,
which includes scores of military designations. |
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