Sikorsky XH-39


The Sikorsky XH-39, developed by Sikorsky Aircraft in 1954, was the U.S. Army's first turbine-powered helicopter. It was fast and innovative, but ultimately rejected by the United States Army in favor of the Bell UH-1 Iroquois.

Design and development

The four-seat XH-39 was powered by one Continental CAE XT51-T-3 400 shp turboshaft engine, a license-built development of the Turbomeca Artouste. It was developed from a previous Sikorsky model, the H-18, and had the same layout. It differed in using retractable landing gear, modified tail rotor, and four-blade main rotor. In the end, the U.S. Army selected the Bell XH-40, prototype of the UH-1 Huey. Two YH-18As were modified into XH-39s; one for flight testing and the other for static test.
On 26 August 1954, the XH-39 set a world helicopter speed record of 156.005 mph over a three kilometer closed course at Bradley Field in Windsor Locks, Connecticut. The same year, on October 17, 1954, it set an unofficial world helicopter altitude record of 24,500 ft at Bridgeport, Connecticut.
In addition to the two XH-39s, one S-59, serial number 52004, registration number N74150, was produced for use for company demonstration flights. It has been restored and is now on display at the New England Air Museum, Windsor Locks, Connecticut.

Variants

;XH-39
;XH-39A

Specifications (XH-39)