relay information to other aircraft, this allows other Apaches to fire on targets identified by only a single helicopter. AgustaWestland have since made several upgrades to Britain's Apache fleet. In May 2005, a $212 million contract was awarded to equip all the Mk1 helicopters with the Apache Arrowhead sensor system upgrade, to be completed by 2010. In 2009, it was announced that AgustaWestland was also integrating new external fuel tanks with ballistic protection. The magazine can be replaced with an Integrated Ammunition and Fuel unit, which reduces the ammunition capacity but increases loitering time. It has been suggested that advanced rotor blades and additional controls to improve the agility of the aircraft may be fitted in a mid-life update of the fleet. Operational history Overview In May 2005, the first Apache-equipped regiment achieved operational status. The Westland Apache has replaced the Westland Lynx AH7 as the British Army's tactical attack helicopter. The Apache is currently operated by two regiments of the Army Air Corps (3 Regt AAC and 4 Regt AAC) as part of 1st Aviation Brigade (United Kingdom). The Apache is intended to operate in the armed reconnaissance and attack roles, similar to the US usage of Apaches during the 1991 Gulf War. Unlike US versions, the Westland Apache has been partially navalised and now serves aboard Royal Navy ships in addition to its land-based role. It achieved maritime certification in December 2005 aboard HMS Ocean. On 17 November 2006, HMS Ark Royal became the first aircraft carrier to land an Apache AH1. They first appeared in combat as part of Operation Herrick in Afghanistan in May 2006. In August 2006, the intense usage of Apaches in Afghanistan led to British commanders admitting that weapons and spare parts were being used at a far greater rate, and subsequently a greater cost, than anticipated. On 11 November 2007, it was reported that half of the Apache gunships in British service had been grounded as they had fallen below the level considered "fit for purpose", along with several other British Helicopters such as the Chinook and Merlin HC3. By November 2008, the situation had further declined, out of 67 aircraft only 20 were available for combat operations. In 2009, AgustaWestland was awarded a contract for support services for the Apache and many components such as the Longbow radar; in the following months senior officers noted that the support change had resulted