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The AgustaWestland AW101, marketed as the EH101 prior to June 2007, is a medium-lift helicopter for military applications but also marketed for civil use.  The helicopter was developed as a joint venture between Westland Helicopters in the UK and Agusta in Italy (now merged as AgustaWestland ), primarily to replace the older Sikorsky Sea King in roles such as the medium-sized transport and anti-submarine warfare .  The aircraft is manufactured at the AgustaWestland factories in Yeovil, England and Vergiate, Italy.

 The AW101 first flew in 9 October 1987, and entered service in 2000.  It is currently in operation with various nations, such as Denmark , Italy , Japan , Portugal and the United Kingdom .  Significant derivatives so far have been the Canadian AgustaWestland CH-149 Cormorant and the now-cancelled American Lockheed Martin VH-71 Kestrel .  The name Merlin is used for aircraft in service with the British, Danish and Portuguese militaries.



In Spring 1977, the UK Ministry of Defence issued a requirement for an anti-submarine warfare (ASW) helicopter to replace the Royal Navy 's Westland Sea Kings , which were becoming inadequate in the face of advances in Soviet submarine technology. Westland Helicopters put together a proposal, designated WG.34, for a three-engined helicopter of similar dimensions to the Sea King; the WG.34 was to feature more autonomy and a greater range than its predecessor. At the same time, Italy's navy (the Marina Militare), was also considering the replacement of its fleet of Sea Kings built by the Italian company Agusta; Westland and Agusta soon began talks regarding joint development of a successor helicopter.

 Agusta and Westland finalised an agreement to work on the project together, and formed a jointly-owned new company, EH Industries Limited (EHI), to pursue the development and marketing of the new helicopter to potential operators.  On 12 June 1981, the UK government confirmed its participation in the project, allocated an initial budget of £20 million to develop nine pre-series examples. A major agreement, which secured funding for the majority of the EH101's development program, was signed by both the British and Italian governments in 1984. At the 1985 Paris Air Show , Agusta showed a mock-up of a utility version of the new helicopter, leading to a more generalised design that could be customised to meet the needs of various civilian or military customers.  The first prototype flew on 9 October 1987.


General characteristics

Crew: 3–4

Capacity: Eight troops or four stretchers (with sonar removed) [ 119 ]

Length: 19.53 m (64 ft 1 in)

Rotor diameter: 18.59 m (61 ft 0 in)

Height: 6.62 m (21 ft 8¾ in)

Disc area: 271.51 m² (2,992.5 ft²)

Empty weight : 10,500 kg (23,149 lb)

Max. takeoff weight : 14,600 kg (32,188 lb)

Powerplant : 3 × Rolls-Royce Turbomeca RTM322 -01 turboshafts , 1,566 kW (2,100 shp ) (take-off power) each



Never exceed speed : 309 km/h (167 knots , 192 mph)

Cruise speed : 278 km/h (150 knots, 278 km/h)

Range : 1,389 (750 nmi , [ 131 ] 863 mi)

Endurance : 5 hours

Service ceiling : 4,575 m (15,000 ft)



Bombs: 4× Sting Ray homing torpedoes or depth charges



 Smiths Industries OMI 20 SEP dual-redundant digital automatic flight control system

 Navigation systems:

BAE Systems LINS 300 ring laser gyro , Litton Italia LISA-4000 strapdown AHRS

Radar :

Selex Galileo Blue Kestrel 5000 maritime surveillance radar


 Racal Orange Reaper ESM


 Thomson Marconi Sonar AQS-903 acoustic processor

 Active/passive sonobuoys

 Thomson Sintra FLASH dipping sonar array