Westland Whirlwind
HAR1, HAR3, HAR5, HAR9 Air-Rescue & HAS7 Anti-Submarine Helicopters
In 1952 the RN received 25 Sikorsky S55 helicopters (designated HAR21 and HAS22) under the Mutual Defence Aid Plan. These proved highly successful and resulted in an order for licence-built versions a year later, the first of which, a Whirlwind HAR1, flew on 15 August 1953. The Pratt and Whitney Wasp (600 shp) powered HAR1 and HAR3 were built in small numbers between 1953 and 1955 and were soon followed by Alvis powered HAR5s. All the HAR models saw extensive service in ships flights, particularly as the planeguard on carriers. The only anti-submarine Whirlwind, the HAS7, first flew on 17 October 1956 and entered squadron service with 845 NAS. in August 1957. It was equipped with a dipping sonar and had provision to carry a torpedo but could not carry both simultaneously. Due to early problems the HAS7 did not see fleet wide service until 1960 and was soon replaced in the anti-submarine role by the Wessex.
The large surplus of HAS7 Whirlwinds saw their use in a commando transport role from 1960 onwards with some being converted to HAR9s with a Rolls Royce Gnome turbine, entering service with SAR flights in 1967. The HAR1, HAR3 and HAR5 were retired from service by the mid 1960s but the HAS7 continued as a training helicopter until 1975. The HAR9 left SAR service in 1977.
A total of 37 various HAR models and 120 HAS7 Whirlwind were built, in addition to 10 HAR21 and 15 HAS22 Sikorsky S55.
(Whirlwind HAS7)
Dimensions: Rotor diameter 16.15 m (53ft) ; Length 12.71 m (41ft 8.5in) ; Rotor Disc Area 204.85 sq.m (2,205.0 sq.ft)
Weights: Maximum Take-off 3538.0 kg (7,800 lb)
Powerplant: one Alvis Leonides Major - 559 kW (750 shp) maximum power.
Performance: Maximum speed 104 mph (167 kph, 90 kt)
Avionics: Dipping sonar
Armament: single lightweight torpedo in place of dipping sonar