Modernisation
In recent years, three other changes have been made. One was the removal of the Sea Dart system, creating an increased deck park for aircraft. The Sea Dart magazines were converted to increase air-to-surface weapons stowage, and new aircrew briefing facilities created under the extended flight deck, both to support the embarkation of RAF Harrier GR7s as a routine part of the air group. The ships have all also been fitted to handle Merlin helicopters. The Merlin HM1 has replaced the Sea King HAS6 in the carrier-borne ASW role. Since the integration of the Harrier GR7, typical deployments have included seven or eight of those aircraft, pushing the Merlin onto the carrier's accompanying Fort-class auxiliaries.
The two most recent wartime deployments of the class have seen them in their secondary LPH role, as it was officially judged that Sea Harriers could provide no useful role in the missions. During those deployments, the class has embarked RAF Chinook helicopters, in lieu of their fixed-wing complement.
Invincible's last refit was in 2004.
Illustrious underwent a 16-month £40m refit at Rosyth Dockyard during 2010/11 in preparation for her new role as a helicopter carrier during the refit of HMS Ocean.
Read more about this topic: Invincible Class Aircraft Carrier