Royal Navy Merlin

Service -

Royal Navy Description Merlin HM MK1 (formerly Merlin EH101) is an Anti-Submarine (ASW) variant of the EH101 helicopter. The first aircraft was delivered in December 1998, to begin the replacement of the ageing ASW Sea King (Mk6). The 44th and final aircraft was delivered in December 2002.

The collaborative programme began in 1979 through EH Industries - the company formed by Agusta of Italy and GKN Westland in the UK. Designed in Western Europe, it is the largest collaborative helicopter project in history.

In 1991 the United Kingdom selected IBM-Aerospace Systems Integration Corporation (ASIC) (subsequently Loral-ASIC, now Lockheed Martin ASIC (LMA)) as prime contractor to complete Royal Navy development, integration of the Mission System and production of 44 aircraft.

Since then progress has been made on the programme through the award of the Collaborative Production Investment contract in March 1992 to EH Industries. Contracts were also awarded to Lockheed Martin ASIC for the Merlin Training System (MTS) in July 1994, and the Merlin Support and Spares Availability System (MSSAS) in July 1996.

The first flight by a production Merlin was on 6 December 1995 and the first mission system fitted Merlin Mk1 flew in January 1997. Royal Navy Intensive Flight Trials began on schedule in December 1998. Work is currently underway on a significant programme to sustain the capability of the in service Merlin Mk1 aircraft to Out of Service Date (OSD) through the Merlin Capability Sustainment Programme (MCSP). The MCSP programme has successfully completed the project Assessment Phase and is currently seeking approval to proceed to the Demonstration Phase and subsequently place a contract to meet the System Requiremnts Document (SRD).

General characteristics / technical performance

The aircraft has a state-of-the-art, integrated mission system, which processes data from an extensive array of on-board sensors, giving Merlin an independent capability to search for, locate and attack submarine targets. It is this autonomous capability which makes Merlin unique among ASW helicopters. The aircraft and its mission system are managed by two computer systems, linked by dual data buses.

The cockpit is designed for operation by a single pilot, with the auto-pilot allowing for hands-off flight for most of the mission. Normally flown by a crew of three - pilot, observer and aircrewman - Merlin is equipped with the Thomson-Marconi active "dunking" sonar which gives enhanced submarine detection ranges, and the GEC Marconi AQS 903 acoustic processor.

All crew stations can access the management computers and operate the tactical displays. These are fed by the Marconi Blue Kestrel radar which possesses full 360-degree coverage and an ability to Track-While-Scan surface contacts. It can also pass tactical information via a datalink to other participating units; a significant capability which has not been utilised by maritime helicopters before. Based at Royal Naval Air Station (RNAS) Culdrose, Cornwall, Merlin is designed to operate in all weathers from the flight decks of both large and small ships (Invincible class aircraft carriers and Type 23 frigates).

It is powered by three Rolls Royce RTM 322 engines, is capable of speeds of up to 150 knots and has a range of 200 nautical miles. It can carry up to four homing torpedoes or depth charges, for use against threat submarines and can provide targeting information via datalink for the prosecution of surface threats. The Merlin retains all the secondary role capability of its predecessor, the Sea King, including loadlifting, casualty evacuation, troop carrying and Search and Rescue.