Is it an H-5? Is it a Dragonfly? No, it’s an S-51, Part 4
Welcome back, gentle reader, and take a seat while yours truly gathers his thoughts. Do you remember the Dragonfly?
In January 1947, a well known British aircraft maker bought a license to produce the Sikorsky S-51 and sell it around the globe, with the exception of North America, thus initiating decades of cooperation with the Sikorsky Aircraft Division of United Aircraft Corporation. This approach allowed Westland Aircraft Limited to bypass the expensive and time consuming design and development of an original helicopter. On the other hand, it did not mesh very well with the efforts of the British government toward the creation of a national helicopter industry, something that was duly noted at the time. In any event, a prototype of the WS-51, as the British-made machine was called, flew in October 1948. United Aircraft shipped six American-made S-51s to the United Kingdom to provide Westland Aircraft employees with some hands on experience and to make demonstration flights for potential customers.
Most WS-51s flew with the Royal Air Force or, even more so, the Royal Navy’s Fleet Air Arm. These rescue and / or ambulance machines were known as, you guessed it, Dragonflies – a name that United Aircraft and the American military did not use. The first 30 WS-51s were seemingly built by hand, without production tooling, to save money.
All but 10 of the WS-51s were powered by a British engine that turned in the opposite direction from the engine of their American-made counterparts. The power transmission mechanism had to be modified accordingly. If truth be told, the WS-51 and the S-51 had virtually no parts in common. This somewhat unusual route was taken because the British government and manufacturing companies in the United Kingdom found it very difficult to acquire the dollars needed to buy American products and parts.
The last member of the S-51 family was internally financed by Westland Aircraft. Known as the WS-51 Widgeon, this attractive five-seat helicopter was fitted with the rotor mast and head of the Sikorsky S-55, a large machine manufactured in the United Kingdom as the WS-55. And yes, the Canada Aviation and Space Museum has an S-55 in its collection, more specifically a historically significant HO4S operated by the Royal Canadian Navy.
All in all, 446 S-48s, S-51s and WS-51s were made in the United States (285) and the United Kingdom (161) between 1943 and 1959. These often underestimated yet robust and reliable helicopters flew for many years in at least 22 countries and colonies on every continent, primarily in military hands. Often bought in small batches, the S-51s and WS-51s were the first helicopters flown by the armed forces of many countries. More importantly perhaps, they firmly established the Sikorsky Aircraft Division of United Aircraft and Westland Aircraft as two of the major helicopter makers in the world.
A number of S-51s and WS-51s can be seen in museums around the globe. Remarkably, the four helicopters operated by the RCAF that were sill airworthy in 1964-65 all ended up in museums, namely
– the Canada Aviation and Space Museum, in Ottawa / Rockcliffe, Ontario,
– the New England Air Museum, in Windsor Locks, Connecticut,
– the American Helicopter Museum and Education Center, in West Chester, Pennsylvania, and
– the Hangar Flight Museum, in Calgary, Alberta.
See ya later, helicopter. Sorry, bad pun.