AP 118 · No. 10 Section II · Aircraft Plate 187 / 189

Plate 187 of 189 · Modern age · Anti-submarine helicopter

EH Industries EH101 Merlin HM.1

Merlin HM.1, painted as ZH821, Morayvia’s EH Industries EH101 Merlin HM.1, the first production Merlin for the Royal Navy, first flown in December 1995, shown at Farnborough in 1996, withdrawn in 2010 and on display at Kinloss since 2019: the Royal Navy’s anti-submarine helicopter, with a five-bladed main rotor 61 ft in diameter with swept, drooped BERP-style tips, three Rolls-Royce Turbomeca RTM322 turboshafts on top of the cabin, a four-bladed tail rotor on the port side of the tail pylon with a tailplane on the starboard side, a chin radome for the Blue Kestrel radar, a sliding cabin door on the starboard side and the main wheels retracting into side sponsons, shown standing on its wheels with the rotors parked: Royal Navy medium grey overall with sand-coloured sealant strips over panel joints, a low-visibility pale blue and pink roundel ahead of a white ‘ROYAL NAVY’ on both sides of the rear fuselage, a small white ‘ZH821’ below it, yellow bars under the cabin windows and dark grey rotor blades, restored to complete flying configuration (at Morayvia it has lost its tail pylon, rotors and radome, so the pylon and rotors follow photographs of ZH821 at Farnborough in 1996, the radome follows in-service HM.1s, the starboard door is shown closed and the main blades are parked with one over the nose).

3D model

Turn it over

A procedural model built in Blender from published dimensions, drawings and photographs, painted as ZH821, Morayvia’s EH Industries EH101 Merlin HM.1, the first production Merlin for the Royal Navy, first flown in December 1995, shown at Farnborough in 1996, withdrawn in 2010 and on display at Kinloss since 2019: the Royal Navy’s anti-submarine helicopter, with a five-bladed main rotor 61 ft in diameter with swept, drooped BERP-style tips, three Rolls-Royce Turbomeca RTM322 turboshafts on top of the cabin, a four-bladed tail rotor on the port side of the tail pylon with a tailplane on the starboard side, a chin radome for the Blue Kestrel radar, a sliding cabin door on the starboard side and the main wheels retracting into side sponsons, shown standing on its wheels with the rotors parked: Royal Navy medium grey overall with sand-coloured sealant strips over panel joints, a low-visibility pale blue and pink roundel ahead of a white ‘ROYAL NAVY’ on both sides of the rear fuselage, a small white ‘ZH821’ below it, yellow bars under the cabin windows and dark grey rotor blades, restored to complete flying configuration (at Morayvia it has lost its tail pylon, rotors and radome, so the pylon and rotors follow photographs of ZH821 at Farnborough in 1996, the radome follows in-service HM.1s, the starboard door is shown closed and the main blades are parked with one over the nose). Drag to orbit, scroll or pinch to zoom · download .glb (1.2 MB)

Data plate

Specification

First flight, number built and top speed are for the whole family (); engine, crew and dimensions are for the Merlin HM.1 modelled here.

History

The Merlin HM.1

In the late 1970s the Royal Navy began looking for a successor to the Sea King, a helicopter big enough to hunt submarines on its own from the new Type 23 frigates, far from a carrier, with its own radar, sonar, weapons and the crew to use them. Italy needed a similar helicopter, and in 1980 Westland and Agusta set up a joint company, European Helicopter Industries, to design one. The result was the EH101, a three-engined helicopter of about 14 tonnes, designed from the start in naval, military and civil versions. The first of nine pre-production machines, PP1, flew at Yeovil on 9 October 1987. In 1991 the Ministry of Defence ordered 44 anti-submarine Merlin HM.1s for the Royal Navy, with Lockheed Martin as prime contractor for the mission system.

The Merlin was a big step on from the Sea King. Three Rolls-Royce Turbomeca RTM322 engines let it keep flying with one shut down, and a five-bladed main rotor with swept, drooped tips, a product of the British Experimental Rotor Programme that had given a Lynx the helicopter speed record in 1986, made it faster and smoother. The radar sat in a radome under the nose, the main wheels folded into side sponsons, and the rotor and tail folded for stowage in a frigate’s hangar. Inside, a computerised mission system brought the radar, dipping sonar, sonobuoys and data link together, so that a crew of four could find and attack a submarine without help from a ship. The first production Merlin, ZH821, flew in December 1995, and the Intensive Flying Trials Unit, 700M Naval Air Squadron, formed at Culdrose in December 1998.

The Merlin HM.1 went to sea with 814, 820 and 829 Naval Air Squadrons, flying from frigates, carriers and auxiliaries, and it deployed to the Gulf and the Indian Ocean as well as the North Atlantic. The RAF bought 22 Merlin HC.3 transports, which later passed to the Commando Helicopter Force as HC.3i and HC.4s, and from 2014 thirty of the Navy’s HM.1s were rebuilt as HM.2s with new cockpits and mission systems, some later fitted with the Crowsnest airborne radar. Agusta and Westland merged as AgustaWestland in 2000, the type was renamed the AW101 in 2007, and it has been sold to Canada, Denmark, Italy, Japan, Norway, Portugal, Saudi Arabia and others, with about 230 built so far. In the gazetteer ZH821 can be seen at Morayvia, and two pre-production machines, PP3 and the civil Heliliner PP8, are at The Helicopter Museum in Weston-super-Mare.

This airframe

Merlin HM.1 ZH821

ZH821The airframe modelled

ZH821 was the first production Merlin HM.1 for the Royal Navy. It first flew in December 1995 and was shown at the Farnborough Air Show in September 1996, then spent its career on trials and service flying before it was withdrawn in March 2010. It was stored at RAF Shawbury from 2013 and moved to Morayvia, at the former RAF Kinloss near Forres, in June 2019. There it is displayed as an incomplete airframe: its tail pylon, rotors and rotor head have been removed, the radome is gone and a tarpaulin covers the top of the gearbox. The model shows it restored to complete flying condition. The fuselage, sponsons, engine housings, glazing, undercarriage and markings follow photographs taken at Morayvia: Royal Navy medium grey overall with sand-coloured sealant strips over the panel joints, a low-visibility pale blue and pink roundel ahead of a white ‘ROYAL NAVY’ on both sides of the rear fuselage, a small white ‘ZH821’ below it, and yellow bars under the cabin windows. The tail pylon, rotor head and dark grey rotor blades follow photographs of ZH821 at Farnborough in 1996, and the radome is the standard HM.1 fit, shaped from photographs of other HM.1s. The starboard cabin door, open with visitor steps at Morayvia, is shown closed.

See it at Morayvia

Where to see one

In the gazetteer

The gazetteer records the Merlin HM.1 in 2 UK collections. The airframe modelled here is marked.

Every airframe and serial All 189 plates

Profiles and models are procedural interpretations built in Blender from published dimensions, three-view drawings and photographs of each airframe. Treat the museum aircraft as the reference.