22 October 1956

Bell XH-40 55-4459 with cowlings and rear doors installed. (U.S. Army)
Bell XH-40 55-4459 with stabilizer bar, cowlings and rear doors installed. (U.S. Army)

22 October 1956: Bell Aircraft Corporation Chief Pilot Floyd W. Carlson and Chief Experimental Test Pilot E.J. Smith, make the first flight of the Bell Model 204, XH-40-BF, serial number 55-4459, at the Bell helicopter factory at Hurst, Texas.

Bell XH-40 first flight. (U.S. Army)
Bell XH-40 first flight. (U.S. Army)

The XH-40 was designed with a primary mission of battlefield medical evacuation. It was 42 feet, 8 inches (13.005 meters) long with a main rotor diameter of 44 feet, 0 inches (13.411 meters). Empty weight was 3,693 pounds (1,675 kilograms) with a maximum gross weight of 5,650 pounds (2,563 kilograms).

The prototype XH-40 was powered by a Lycoming LTC1B-1 (XT53-L-1) free-turbine (turboshaft). The engine uses a 5-stage axial-flow, 1-stage centrifugal-flow compressor with a single-stage gas producer turbine and single-stage power turbine. A reverse-flow combustion section with 12 burners allows a significant reduction in the the engine’s total length.  engine with a Maximum Continuous Power rating of 770 shaft horsepower. The Military Power rating was 825 shaft horsepower. It could produce 860 shaft horsepower at 21,510 r.p.m.  At Military Power, the XT53-L-1 produced 102 pounds of jet thrust (0.454 kilonewtons). The power turbine drives the output shaft through a 3.22:1 gear reduction. The T53-L-1 is 3 feet, 11.8 inches (1.214 meters) long and 1 foot, 11.25 inches (0.591 meters) in diameter. It weighs 460 pounds (209 kilograms).

The helicopter had a maximum speed of 138 miles per hour (222 kilometers per hour). The service ceiling was 17,500 feet (5,334 meters) and its range was 212 miles (341 kilometers).

The Bell XH-40 prototype hovering in ground effect at the Bell Aircraft Company plant at Hurst, Texas. The helicopter's cowlings are not installed in this photograph. (U.S. Army)
The Bell XH-40 prototype hovering in ground effect at the Bell Aircraft Corporation plant at Hurst, Texas. The helicopter’s cowlings and doors are not installed in this photograph. (U.S. Army)

This aircraft was the prototype of what would be known world-wide as the “Huey.” The helicopter was originally designated by the U.S. Army as HU-1, but a service-wide reorganization of aircraft designations resulted in that being changed to UH-1A. Produced for both civil and military customers, it evolved to the Model 205 (UH-1D—UH-1H), the twin-engine Model 212 (UH-1N), the heavy-lift Model 214, and is still in production 60 years later as the twin-engine, four-bladed, glass-cockpit Model 412EPI and the UH-1Y.

Left rear quarter view of the Bell XH-40 hovering in ground effect at the Bell Helicopter Company plant at Hurst, Texas. (U.S. Army)
Left rear quarter view of the Bell XH-40 hovering in ground effect at the Bell Helicopter Company plant at Hurst, Texas. (U.S. Army)

Sources differ as to the date of the first flight, with some saying 20 October, and at least one saying 26 October, but most cite 22 October 1956. This individual aircraft is at the U.S. Army Aviation Museum, Fort Rucker, Alabama. The museum’s director, Robert S. Maxham, informed TDiA that, “The earliest and only historical record cards that we have on 4459 are dated 2 MAY 1958, and at that time the aircraft had 225.8 hours on it.” The Smithsonian Institution National Air and Space Museum, a generally reliable source, states the first flight was 22 October 1956.

The earliest contemporary news report yet discovered by TDiA, states,

On October 20, after several hours of ground running, the new Bell XH-40 helicopter was flown for the first time.

FLIGHT and AIRCRAFT ENGINEER, No. 2506, Vol. 71, Friday, 1 February 1957, Page 136, at Column 1

The first prototype Bell XH-40, 55-4459, hovers in ground effect. (U.S. Army)

Beginning in 2015, XH-40 55-4459 was restored by Blast Off, Inc., at Atmore, Alabama. It was then returned to the Army Aviation Museum.

Bell XH-40 55-4459 ready for transport to Blast Off, Inc., 16 June 2015. (The Atmore Advance)

© 2017, Bryan R. Swopes

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