The HC4 (Helicopter Commando Mk 4) is a troop carrying variant developed by Westland from the original Anti Submarine version. The cabin can seat 27 troops and there is an external cargo hook for carrying underslung loads (USLs) such as Land Rovers and Light Artillery up to about 2.5 tonnes. A hoist is fitted as standard.
The aircraft has a good defensive aids suite offering limited protection from many known anti-aircraft weapons. This comprises a Radar Warning Receiver, Missile Approach Warning System, Infra Red Jammer, Chaff and Flares. Finally there is a cabin mounted General Purpose Machine Gun.
The Sea King is well suited to deck operations, is a stable platform for Instrument Flight and has a limited ability to fly in icing conditions, all of which means it can fly in weather that would ground other types of helicopter currently in service. The aircraft is fully NVG (Night Vision Goggle) compatible.
Commando Helicopter Force also operates Sea King Mk 6. Originally designed as a ASW platform, it has recently been converted into the commando role