The Bell R-12 (later redesignated H-12 ; company Model 48 ) was an American 1940s military utility helicopter built by the Bell Helicopter company. The design did not go into full production, but over a dozen prototypes were used for various tests and projects.
6-480: (Redirected from H-12 ) H12 may refer to: Vehicles [ edit ] Bell H-12 , an American utility helicopter Curtiss H-12 , an American flying boat Hiller H-12 , an American helicopter HMS Achates (H12) , a Royal Navy A-class destroyer HMS H12 , a Royal Navy H-class submarine LSWR H12 class , a British steam railcar Other uses [ edit ] H-12, Islamabad , site of
12-485: A campus of the National University of Sciences & Technology Highway H12 (Ukraine) London Buses route H12 , a Transport for London contracted bus route [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to
18-573: A more powerful 600 hp (447 kW) Pratt & Whitney R-1340-55 engine was also ordered, followed by ten pre-series YR-12B helicopters, with a glazed nose, instead of the car-like nose of the Model 42 and XR-12. While under flight test the helicopter was redesignated the H-12 , but the results were not satisfactory, as there were major problems with the main rotor due to blade weaving and poor rotor governor performance. No production H-12 aircraft were built but
24-539: A new utility helicopter, the Model 42, much larger than the Model 47 , which utilized a scaled-up version of the Model 47's rotor system. Three prototypes were built, but serious rotor problems and complexity of mechanical systems precluded production. The initial Model 42 variant was civilian, but the United States Air Force ordered the development of its military variant, the Model 48 . Two prototypes were ordered as
30-518: The XR-12 , powered by a single 540 hp (403 kW) Pratt & Whitney R-1340-AN-1 radial engine and featuring seating for five. Of very similar construction to the Model 42, the Model 48 had a shorter rotor mast. A production batch of 34 helicopters was ordered, under the designation R-12A, but cancelled in 1947. Another enlarged prototype (the XR-12B, Model 48A) with seats for eight plus two pilots and
36-400: The intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=H12&oldid=1085847332 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Bell H-12 During 1946, Bell Helicopter began development of
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