STATUS: Retired, Out-of-Service
MANUFACTURER(S): Sikorsky Helicopters - USA
OPERATORS: Argentina; Australia; Canada; China (Taiwan); France; Netherlands; South Africa; United Kingdom; United States
POWER: 1 x Pratt & Whitney R-985 "Wasp Junior" engine developing 450 horsepower and driving a three-bladed main rotor and a three-bladed tail rotor.
Detailing the development and operational history of the Sikorsky H-5 Light Utility Helicopter.
Entry last updated on 8/24/2018.
Authored by Staff Writer. Content ©www.MilitaryFactory.com.
The road to finding a viable over-battlefield helicopter was a long and arduous one. Helicopters began receiving serious military consideration during World War 2 (1939-1945) when technology finally began supporting their type under the stresses of war. The Germans experimented with several notable helicopters during the conflict that included several offerings from both Flettner and Focke-Achgelis. In the United States, the concern of Sikorsky eventually took the lead in helicopter development for the Americans, revealing the VS-300 (under the Vought-Sikorsky brand label) in September of 1939. By the end of war came the R-6 model of which 25 were produced and operated with the United States Navy (USN) and Royal Air Force (RAF) services.
Development and Walk-Around
Back on August 18th, 1943, Sikorsky recorded a first-flight for their new VS-327, a light, single-engined utility-type helicopter destined for military and civilian market service. The design was intended as a more powerful alternative to the earlier R-4 with changes made to suit higher operating tolerances - mainly in the main rotor diameter and extensive fuselage modifications. The result was a slimmer aircraft with a three-bladed main rotor unit seated overhead and a two-bladed tail rotor unit facing portside. A wheeled, fixed undercarriage was used for ground-running (early forms had a tail wheel arrangement, later forms utilized a tricycle). The crew of two sat in tandem under a heavily-framed canopy. The engine was held in a compartment aft of the crew cabin.
Dimensions included an overall length of 57 feet, a width (including the main rotor diameter) of 48 feet and a height of 13 feet. Empty weight was 3,780lb against a loaded weight of 4,825lb. Beyond the typical seating for two crew, the helicopter had an in-built capability to carry two medical litters on external panniers - these being essentially "baskets" slung over the sides of the fuselage.
To power the new creation, the Pratt & Whitney R-985-AN-5 "Wasp Junior" radial piston engine was used which outputted 450 horsepower. With this installation, the VS-327 was quick to offer the expected performance and capability gains which led to interest by the United States military. Performance with the Wasp Junior engine allowed for a maximum speed of 106 mph to be reached and range was out to 360 miles. The helicopter's service ceiling reached 14,400 feet and climb to 10,000 ft could be done in about 15 minutes.
The prototype was designated XR-5 and five were built to the standard set by the VS-372. With some slight changes made, these evolved to the developmental YR-5A models which became twenty-six examples. Once in service, the product graduated to the R-5A mark and thirty-five were produced for the Search and Rescue (SAR) / MEDEVAC role. R-5A models were later redesignated to H-5A. The R-5B was a proposed, modified R-5A but not followed through on. Similarly, the developmental YR-5C was not furthered.
Sikorsky H-5 (Cont'd)
Light Utility Helicopter
The R-5D introduced a more conventional tricycle undercarriage arrangement and these were built from the R-5A stock and retained their SAR capabilities including equipment fittings. The R-5D was later redesignated to H-5D. The YR-5E was the YR-5A with a dual-control scheme allowing either crewman to control the helicopter. Five were converted to the standard and these later became the YH-5E. The R-5F was produced from 1947 onward for the civilian market and featured seating for four. Eleven were built and these later became the H-5F. Another civilian market model was the S-51 - the USN took on four of the type into service.
Thirty-nine examples made up the H-5G mark and, like the R-5F, these held seating for four but retained an SAR capability. The H-5H was the H-5G though wit updated equipment. Sixteen were built to the standard.
The USN tested the R-5 series through two examples as the HO2S-1 and initially held an interest for thirty-four of the type. However, the service passed on the design and the United States Coast Guard (USCG) and canceled their procurement order. The four-seat HO3S-1, based in the H-5F, was taken into service through eighty-eight examples. The HO3S-1G were nine HO3S-1 platforms operated by the USCG. the HO3S-3 became a proposed navalized model of the H-5H but this model was not evolved. A new rotor was used in the one-off HO3S-3 when tested in 1950.
Over 300 H-5 helicopters were eventually produced. Operators included Argentina, Australia, Canada, the Republic of China (Taiwan), France, the Netherlands, South Africa, the United Kingdom and, of course, the United States. All four of the major U.S. military services operated the type in form (and role) or another. The British took to license production of the series under the Westland brand label as the WS-51 "Dragonfly" (detailed elsewhere on this site). One hundred thirty-three were produced for the Royal Navy and Royal Air Force from 1949 to 1954. Service entry occurred in 1950 and the Westland Widgeon was a notable offshoot of the British work on the product. Royal Canadian Air Force (RCAF) operation of the H-5 was primarily centered on training to fly helicopters and testing various configurations and technologies on the platforms they received.
It took some time for the helicopter to became a useful battlefield component and its importance grew during the Korean War of 1950-1953. It was not until the American involvement in the Vietnam War (1955-1975) that the helicopter truly came into its own over the battlefield (thanks largely due to the development of an effective turboshaft engine). The design graduated to become troop transports, SAR platforms, reconnaissance units, MEDEVAC systems and even armed gunships. It was, however, through contributions like that of the Sikorsky H-5 series that ultimately made this possible.
Our Data Modules allow for quick visual reference when comparing a single entry against contemporary designs. Areas covered include general ratings, speed assessments, and relative ranges based on distances between major cities.
This entry's maximum listed speed (106mph).
Graph average of 90 miles-per-hour.
Graph showcases the Sikorsky H-5's operational range (on internal fuel) when compared to distances between major cities.
Useful in showcasing the era cross-over of particular aircraft/aerospace designs.
Comm. Market HI*: 44,000 units
Military Market HI**: 36,183 units