Introduction to service
The Nimrod first entered squadron service with the RAF at RAF St Mawgan in October 1969. These initial aircraft, designated as Nimrod MR1, were intended as a stop-gap measure, and thus were initially equipped with many of the same sensors and equipment as the Shackletons they were supplementing. While some improvements were implemented on the MR1 fleet to enhance their detection capabilities, the improved Nimrod MR2 variant entered service in August 1979 following a lengthy development process. The majority of the Nimrod fleet operated from RAF Kinloss.
Operationally, each active Nimrod would form a single piece of a complex submarine detection and monitoring mission. An emphasis on real-time intelligence sharing was paramount to these operations; upon detecting a submarine, Nimrod aircrews would inform Royal Navy frigates and other NATO-aligned vessels to pursuit in an effort to continuously monitor Soviet submarines. The safeguarding of the Royal Navy's Resolution-class ballistic missile submarines, which were the launch platform for Britain's nuclear deterrent, was viewed as being of the utmost priority.
Nimrods were first deployed to Wideawake airfield on Ascension Island on 5 April 1982, the type at first being used to fly local patrols around Ascension to guard against potential Argentine attacks, and to escort the British Task Force as it sailed south towards the Falkands, with Nimrods also being used to provide search and rescue as well as communications relay support of the Operation Black Buck bombing raids by Avro Vulcans. As the Task Force neared what would become the combat theatre and the threat from Argentine submarines rose, the more capable Nimrod MR2s took on operations initially performed by older Nimrod MR1s. Aviation author Chris Chant has claimed that the Nimrod R1 also conducted electronic intelligence missions operating from Punta Arenas in neutral Chile.
The addition of air-to-air refuelling probes allowed operations to be carried out in the vicinity of the Falklands, while the aircraft's armament was supplemented by the addition of 1,000 lb (450 kg) general purpose bombs, BL755 cluster bombs and AIM-9 Sidewinder air-to-air missiles. The use of air-to-air refuelling allowed extremely long reconnaissance missions to be mounted, one example being a 19-hour 15-minute patrol conducted on 15 May 1982, which passed within 60 miles (97 km) of the Argentine coast to confirm that Argentine surface vessels were not at sea. Another long-range flight was carried out by an MR2 on the night of 20/21 May, covering a total of 8,453 miles (13,609 km), the longest distance flight carried out during the Falklands War. In all, Nimrods flew 111 missions from Ascension in support of British operations during the Falklands War.
A detachment of three Nimrod MR2s was deployed to Seeb in Oman in August 1990 as a result of the Iraqi invasion of Kuwait, carrying out patrols over the Gulf of Oman and Persian Gulf. Due to the level of threats present in the Gulf theatre, operational Nimrods were quickly retrofitted with a Marconi-towed active decoy. Once hostilities commenced, the Nimrod detachment, by now increased to five aircraft, concentrated on night patrols, with daylight patrols carried out by US Navy Lockheed P-3 Orions. Nimrods were used to guide Westland Lynx helicopters and Grumman A-6 Intruder attack aircraft against Iraqi patrol vessels, being credited with assisting in sinking or damaging 16 Iraqi vessels.
Nimrods were often deployed to the Middle East
After the ground offensive against Iraqi forces had ended, Britain elected to maintain an RAF presence in the region through assets such as the Nimrod and other aircraft. Nimrod R1s operated from August 1990 to March 1991 from Cyprus, providing almost continuous flying operations from the start of the ground offensive. Each R1 was retrofitted with the same Marconi towed active decoy as well as under wing chaff/flare dispensers, reportedly sourced from the Tornado fleet.
Afghanistan and Iraq War
Nimrods were again deployed to the Middle East as part of the British contribution to the US-led invasion of Afghanistan; missions in this theatre involved the Nimrods performing lengthy overland flights for intelligence-gathering purposes. On 2 September 2006, 12 RAF personnel were killed when a Nimrod MR2 was destroyed in a midair explosion following an onboard fire over Afghanistan, it was the single greatest loss of British life since the Falklands War. The outbreak of the Iraq War in March 2003 saw the RAF's Nimrods being used for operations over Iraq, using the aircraft's sensors to detect hostile forces and to direct attacks by friendly coalition forces.
Search and rescue
While the Nimrod MR1/MR2 was in service, one aircraft from each of the squadrons on rotation was available for search and rescue operations at one-hour standby. The standby aircraft carried two sets of Lindholme Gear in the weapons bay. Usually one other Nimrod airborne on a training mission would also carry a set of Lindholme Gear. As well as using the aircraft sensors to find aircraft or ships in trouble, it was used to find survivors in the water, with a capability to search areas of up to 20,000 square miles (52,000 km2). The main role would normally be to act as on-scene rescue coordinator to control ships, fixed-wing aircraft, and helicopters in the search area.
The Nimrod was most often featured in the media in relation to its search-and-rescue role, such as in the reporting of major rescue incidents.In August 1979, several Nimrods were involved in locating yachting competitors during the disaster-stricken 1979 Fastnet race and coordinated with helicopters in searches for survivors from lost vessels. In March 1980, the Alexander L. Kielland was a Norwegian semi-submersible drilling rig that capsized whilst working in the Ekofisk oil field killing 123 people; six different Nimrods searched for survivors and took turns to provide rescue co-ordination, involving the control of 80 surface ships and 20 British and Norwegian helicopters. In an example of the search capabilities, in September 1977 when an attempted crossing of the North Atlantic in a Zodiac inflatable dinghy went wrong, a Nimrod found the collapsed dinghy and directed a ship to it.
The Nimrods were often used to enforce Operation Tapestry. Tapestry is a codeword for the activities by ships and aircraft that protect the United Kingdom's Sovereign Sea Areas, including the protection of fishing rights and oil and gas extraction. Following the establishment of a 200 nautical miles (370 km) Exclusive Economic Zone (EEZ) at the beginning of 1977 the Nimrod fleet was given the task of patrolling the 270,000 square miles (700,000 km2) area. The aircraft would locate, identify, and photograph vessels operating in the EEZ. The whole area was routinely patrolled; in addition to surveillance, the aircraft would communicate with all oil and gas platforms. In 1978, an airborne Nimrod arrested an illegal fishing vessel in the Western Approaches and made the vessel proceed to Milford Haven for further investigation. During the Icelandic Cod Wars of 1972 and 1975–1976, the Nimrod fleet closely cooperated with Royal Navy surface vessels to protect British civilian fishing ships.