Air Platforms

UK completes Merlin HC3/3A helo upgrades

11 February 2020

The first of 25 upgraded Merlin HC4/4A helicopters for the Commando Helicopter Force making its maiden flight in late October 2016. With all 18 HC3/3A helicopters having gone through the process, seven interim maritime iHC3-standard platforms will now be upgraded through to the end of the year for a final fleet of 25 HC4/4A helicopters. Source: Royal Navy

The UK has upgraded the last of its AgustaWestland Merlin HC3/3A transport and assault helicopters for littoral use by the Royal Navy (RN) and Royal Marines (RM).

The commanding officer of 845 Naval Air Squadron (NAS), RN Commander Bob Bond, tweeted on 11 February that the final HC3A helicopter had departed Royal Naval Air Station Yeovilton, southern England, bringing to an end the mid-life sustainment effort that began in 2016.

As noted by the commander, "a small number" of interim maritime iHC3-standard platforms remain to go through the upgrade process before all 25 helicopters are at the final Commando Merlin HC4/4A standard.

The Merlins were transferred from the Royal Air Force (RAF) to the RN Commando Helicopter Force (CHF) in July 2015, being delivered in a baseline HC3/3A 'land' configuration. Seven of these were then modified to the interim iHC3 configuration to bridge an operational capability gap between the retirement of the Westland Commando HC4s on 31 March 2016 and the introduction into service of the Merlin HC4/4A in September 2017.

This iHC3 configuration included equipping the helicopters with a folding main rotor head (no tail fold); a fast rope point; modified undercarriage for deck operations; and new deck mooring points. The seven iHC3 helicopters were delivered to the CHF's 846 NAS and 845 NAS at Royal Naval Air Station (RNAS) Yeovilton in time for the retirement date of the Commando.

The HC4/4A conversion programme built on the iHC3 configuration with a tail fold assembly, a life sustainment package to solve HC3/3A obsolescence issues, and an avionics upgrade to include a 'glass cockpit' common to the RN's Merlin HM2 and similar to the Lynx Wildcat.

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