[7] Type 42s were designed as anti-aircraft vessels primarily equipped with the Sea Dart, a surface-to-air missile system capable of hitting targets up to 56 kilometres (30 nmi) away.

[8] Cardiff's secondary weapon system was a 4.5 inch Mark 8 naval gun, capable of firing 21-kilogram (46 lb) shells to a range of 22 kilometres (12 nmi).

[9] After the Falklands War, in which two Type 42s were sunk by enemy aircraft, the entire class was equipped with the Phalanx close-in weapon system,[10] a Gatling cannon that could fire 3,000 rounds per minute and was designed to shoot down anti-ship missiles.

[14] Just over a month before the start of the war, Cardiff, under the command of Captain Michael Harris,[16] had begun a six-month deployment to the Persian Gulf with the Armilla Patrol.

Cardiff had relieved her sister ship and class lead Sheffield from this operational tasking,[17] but was herself redeployed to the Falklands effort on 23 April.

[18] During the journey, Cardiff's crew performed various training exercises, including defence against air attack (involving simulation runs by friendly Harrier and Jaguar aircraft), nuclear, biological, and chemical weapons and Exocet anti-ship missiles.

[25][26] Cardiff's primary role was to form part of the anti-aircraft warfare picket, protecting British ships from air attack and attempting to ambush Argentine aircraft that were re-supplying Port Stanley Airport.

[29][30] All four on board were killed,[31] the factors contributing to the accident were a poor level of communication between the army and navy, and the helicopter's "Identification Friend or Foe" transmitter had been turned off due to it interfering with other equipment.

[17] Having been told there were no other British forces in the area, Cardiff's crew assumed they were Argentine, and fired illuminating star shells over them in preparation to attack.

When the Guards saw the star shells and realised Cardiff's intentions, the officer in charge of the landing craft, Major Ewen Southby-Tailyour, moved them to shallow water in an attempt to outrun her.

Poor weather had forced the Argentine craft to abandon their original mission of bombing Mount Longdon, and the third Dagger of their formation had suffered a mechanical failure and returned to base.

[19] Five members of Cardiff's crew were used to man a captured Argentine patrol boat, renamed HMS Tiger Bay, in Stanley.

[40] Cardiff spent the rest of June acting as the Landing Area Air Warfare Controller (LAAWC) around San Carlos.

[10] When Saddam Hussein's Iraq invaded Kuwait on 2 August 1990, British Secretary of State for Defence Tom King soon announced that the UK military contribution to the region was to be increased.

[41] Cardiff and Gloucester were to form part of the air defence barrier along with Bunker Hill, Princeton and Worden protecting three United States aircraft carriers: Midway, Ranger and Theodore Roosevelt.

[43] In total, Lynx helicopters flew nearly 600 sorties during the Gulf War,[41] while their crews and engineers maintained flying rates three times their norm.

[44] Despite her parent ship dodging mines and maintaining the air defence line as the closest non-US to Kuwait for the first 4 weeks of the 1991 War, Cardiff's Lynx helicopter, no.

The operation was designed to deter Saddam Hussein's "sabre-rattling" by sending large amounts of allied military forces to Kuwait; Cornwall and Cardiff were the UK contribution.

[50] In 2000, as part of the Royal Navy's Atlantic Patrol Task North, Cardiff spent six months in the Caribbean with RFA Black Rover.

In addition to clearing routes, distributing supplies, and making buildings and electrical cables safe, Cardiff's surgeon and medical team monitored sanitation.

[57] During her time in the Persian Gulf, Cardiff prevented more than £2 million of illegal cargo from being smuggled out of Iraq, inspected 178 vessels, and seized more than 25,000 tonnes of oil.

[58] In late 2003, the ship was involved in the annual Sea Days demonstration exercise,[59] and in October was used for tests of QinetiQ's Maritime Tactical Network.

[63] However, it was announced in July 2004 that she would be one of a number of ships withdrawn from service early, in accordance with the "Delivering Security in a Changing World" white paper on the British military.

[4] She then stayed in Portsmouth Harbour at Fareham Creek (50°49′07″N 1°07′50″W / 50.818486°N 1.130644°W / 50.818486; -1.130644) alongside sister ship Newcastle, where both were heavily cannibalised to keep the remaining Type 42 Destroyers running.

[67][68] Calls were made for the conversion of the ship into a Cardiff tourist attraction by a Member of the National Assembly for Wales and former naval servicemen.