AgustaWestland AW101 Merlin

The AgustaWestland AW101 is a medium-lift helicopter used in both military and civil applications. It was developed by joint venture between Westland Helicopters in the UK and Agusta in Italy in response to national requirements for a modern naval utility helicopter; until 2007, the aircraft had been marketed under the designation EH101. Several operators, including the armed forces of Britain, Denmark and Portugal, use the name Merlin for their AW101 aircraft. It is manufactured at factories in Yeovil, England and Vergiate, Italy; licensed assembly work has also taken place in Canada, Japan and the United States.

In 2000, Westland Helicopters and Agusta merged to form AgustaWestland, leading to the type's redesignation as AW101. The AW101 first flew in 1987, and entered into service in 1999. Since the AW101's introduction it has replaced several older helicopter types such as the Sikorsky S-61, performing roles such as medium-sized transport, anti-submarine warfare, and ship-based utility operations.

The Canadian Forces Air Command (CFAIRCOM) and Canadian Forces Maritime Command (CFMARCOM) operates a variant of the AW101, designated CH-149 Cormorant, in the air-sea rescue role. Another variant, designated Lockheed Martin VH-71 Kestrel, was developed to serve in the US presidential transport fleet.

Variants

 * Pre-production helicopters:
 * PP1: Westland-built basic air vehicle prototype, first flown on October 9th, 1987.
 * PP2: Agusta-built Italian basic air vehicle prototype first flown on November 26th 1987 and used for deck trials but was destroyed on January 21st 1993 following a rotor brake malfunction.
 * PP3: Westland-built and the first civil configured Heliliner, used for engine vibration tests and icing trials in Canada.
 * PP4: Westland-built British naval prototype, lost in an accident on April 7th 1995 after a drive train control rod failure.
 * PP5: Westland-built Merlin development aircraft eventually equipped with Merlin avionics.
 * PP6: Agusta-built development aircraft for Italian Navy variant first flown April 26th, 1989.
 * PP7: Agusta-built military utility aircraft with rear-loading ramp.
 * PP8: Westland-built civil prototype.
 * PP9: Agusta-built military utility prototype with rear-loading ramp.
 * Model 110: Italian Navy ASW/ASuW variant, eight built. Powered by T-700-GE-T6A1 engines. Fitted with Eliradar APS-784 radar and Honeywell HELRAS dipping sonar. Armed with torpedoes or Marte anti-ship missiles.
 * Model 111: Royal Navy ASW/ASuW variant, designated Merlin HM1 by customer. Powered by RTM322 engines and fitted with Blue Kestrel radar, Thomson Marconi FLASH dipping sonar and Orange Reaper ESM. 44 built.
 * Model 112: Italian Navy early warning variant with same airframe as Model 110 but with Eliradar HEW-784 radar in large underfuselage radome. Four built.
 * Series 200: Proposed military utility version with no rear-loading ramp.
 * Series 300 Heliliner: Proposed civil transport with no ramp. In 2000, British International Helicopters conducted service trials using PP8; these did not lead to a commercial service.
 * Series 310: Proposed version of Heliliner with full airline avionics for operation from oil platforms. No production.
 * Model 410: Italian Navy transport variant with folding rotors and tail boom. Four built.
 * Model 411: Royal Air Force transport variant, designated Merlin HC3 by customer, 22 built.
 * Model 413: Italian Navy special forces and amphibious assault transport with more advanced avionics.
 * Model 500: Proposed civil utility variant with rear-ramp.
 * Model 510: Civil utility variant with rear ramp, two built. One used for Tokyo Metropolitan Police Agency and one used to support US101 bid.
 * Model 511: Canadian military search and rescue variant, designated CH-149 Cormorant by customer.
 * Model 512: Merlin Joint Supporter for Royal Danish Air Force. Eight acquired for search and rescue (512 SAR) and six for tactical troop transport (512 TTT). The six transports were sold to RAF (as Merlin HC3As) and replaced by six new-build Merlins.
 * Model 514: Portuguese Air Force search and rescue variant, six built.
 * Model 515: Portuguese Air Force fisheries protection variant, two built.
 * Model 516: Portuguese Air Force combat search and rescue variant, four built.
 * Model 518: Japanese Maritime Self-Defense Force mine countermeasures and transport variant, two built.
 * Model 519: Presidential Transport variant for the United States Marine Corps as the VH-71 Kestrel, four test vehicles and five pilot production aircraft, and twenty-three production model built.
 * Model 610: Algerian Naval variant. 6 delivered.
 * Model 611: Italian Air Force Combat Search and Rescue variant. 15 on order.
 * Model 612: Norwegian search and rescue variant, operated by the Air Force. 16 ordered with option for 6 more.
 * Model 640: Saudi Arabian VVIP variant, operated by the Air Force. 2 delivered.
 * Model 641: Indian VVIP variant.
 * Model 642: Algerian VVIP variant, 2 delivered.
 * Model 643: Turkmenistani VVIP variant, operated by the Air Force. 2 delivered.
 * Model 644: Nigerian VVIP variant.
 * Model 645: Azerbaijani VVIP variant.

Users

 * Algeria
 * Algerian Air Force
 * Algerian Navy
 * Azerbaijan
 * Azerbaijani Air and Air Defence Force
 * Canada - see AgustaWestland CH-149 Cormorant
 * Royal Canadian Air Force
 * Royal Canadian Navy
 * Denmark
 * Royal Danish Air Force
 * India
 * Indian Naval Air Arm
 * Indonesia
 * Indonesian Air Force
 * Italy
 * Aeronautica Militare
 * Marina Militare
 * Japan
 * Japan Maritime Self-Defense Force
 * Tokyo Metropolitan Police Department
 * Nigeria
 * Nigerian Air Force
 * Norway
 * Royal Norwegian Air Force
 * Poland
 * Polish Navy
 * Portugal
 * Portuguese Air Force
 * Saudi Arabia
 * Royal Saudi Air Force
 * Turkmenistan
 * Turkem Air Force
 * United Kingdom
 * Royal Air Force
 * Royal Navy
 * United States
 * United States Marine Corps - see Lockheed Martin VH-71 Kestrel

Related Development

 * AgustaWestland CH-149 Cormorant
 * Lockheed Martin VH-71 Kestrel

Comparable Aircraft

 * Changhe Z-18F
 * Eurocopter EC725 Caracal
 * Mil Mi-17
 * Mil Mi-38
 * Sikorsky CH-148 Cyclone