UNITED24 - Make a charitable donation in support of Ukraine!


RAF Airborne Early Warning

Airborne Early Warning (AEW) in British service can trace its roots back to the Second World War when the need to protect the Atlantic and Arctic convoys from German warships and long range Focke-Wulf Condors was identified. It had become obvious that the land based Chain Home radar stations were unable to provide any "over the horizon" cover for these essential supply routes and trials were held with a radar fitted to a Wellington bomber. Tests using this system were on the whole unsuccessful and it wouldn't be until 1952 that Britain would have an operational system brought from America under the Mutual Defence Assistance Program.

The Japanese attack on Pearl Harbour made the Americans realise that they also had the requirement for a long range radar system and began the development of their own airborne early warning radar platform. This development led the General Electric company to build the AN/APS 20 radar. Towards the end of the war the U.S. Navy was operating Grumman TBM-3W Avengers fitted with this new radar from it's Pacific Fleet carriers. Unfortunately the system was in its infancy and their effectiveness against the Japanese kamikaze threat was not as great as had been hoped.

Further development after the war led to an upgraded version of the same radar being fitted to the Douglas AD-4W Skyraider and it was this aircraft that in 1952 was delivered to the Fleet Air Arm's No 849 Sqn. Designated Skyraider AEW-1 they were deployed onto the Navy's aircraft carriers and remained in service until 1960 when the same squadron re-equipped with the Fairey Gannet AEW Mk-3. Though the Gannet was an entirely new aircraft the radar was the same AN/APS 20 previously fitted to the Skyraiders and as on the American aircraft was mounted in a bulbous pod below and just forward of the wing.

The Navy's decision to phase out fixed wing operations during the early 1970s led to the task of providing AEW cover to the fleet being transferred to the Royal Air Force. It was decided that twelve low hour Shackleton MR Mk 2s would be converted as an "interim solution" until a new purpose built aircraft could be procured. Again, the same podded AN/APS 20 radar sets were fitted to the Avro designed airframes and No. 8 Sqn was declared operational with the Shackleton AEW2 at Lossiemouth in 1972.

Though the Air Force was able to provide limited AEW cover for the fleet, the decommissioning of HMS Ark Royal in 1978 and subsequent retirement of the Gannet fleet left the Navy without the ability to provide long range radar protection when deployed overseas. This situation was highlighted with disastrous consequences when Argentina invaded the Falkland Islands in 1982. In response to the invasion the Task Force set sail from British waters and headed south without an airborne radar platform to provide warning of Argentinean attacks. The losses of ships such as HMS Sheffield, Antelope, Ardent and the Atlantic Conveyer to sea-skimming Exocet anti-ship missiles and low level strike aircraft led the Navy to urgently restore its own AEW cover. Though too late for the conflict in the South Atlantic this requirement led to development of the Searchwater radar equipped Sea King HAS1, sometimes refered to as the AEW2. Today fleet AEW cover is provided by these upgraded Sea Kings aboard all of the Navy's carriers.

Throughout the 1970s the need to replace the ageing Shackletons gathered pace. At the same time Boeing was offering the Boeing 707 based E-3A to all NATO countries interested in providing its own AWACs / AEW. It was soon realised that the cost of the E-3 was way beyond the budgets of most member nations so Boeing then offered the aircraft to the 'organisation'. However, the inability of the member nations to come to an agreement on how and when this fleet of aircraft would be operated led to the British Government to go it alone in 1977 and order the Nimrod AEW-3 for the Royal Air Force. It was also decided that the Nimrod would be made available for sale to NATO to fulfil their requirement once development was complete. (Subsequently NATO decided to order the American solution and deliveries of the ten E-3A aircraft began at Geilenkirchen, Germany in 1982).

The Shackleton AEW2 'interim solution' had by now been in service for fifteen years and extensive defence cuts in 1981 saw the fleet cut by 50% to just six aircraft. Though professionally maintained to the highest possible standards the airframes were beginning to show their age. With the delivery of the first Sentry AEW1 not due until March 1991, No. 8 Squadron's six veterans had another four years of operational service ahead of them. It had been decided that the new AEW fleet would be based at Waddington and to facilitate this in 1990 No. 8 Squadron was split into two elements. No. 8 Sqn North remained at Lossiemouth operating the Shackletons while No. 8 Sqn South headed across the border and began to prepare the Lincolnshire airbase to receive their new charges. On 1 July 1991, five of the six remaining Shackletons were flown to Waddington for the ceremony which would see the Squadron's standard be handed from OC No. 8 Sqn North to OC No. 8 Sqn South. The day marked the end of a nineteen year 'temporary solution' and from that day onward the fleet of seven Sentry AEW1s have been responsible for the providing Royal Air Force's AEW commitment to NATO. It also ended an uninterrupted 39 years of British service by the World War II vintage AN/APS 20 radar.

In 1996 No. 23 Squadron was reformed as part of the Waddington AEW Wing and shares the seven aircraft with No. 8 Squadron, consequently all seven aircraft carry the markings of both units. The Sentry AEW1 is a Boeing 707-320B airframe packed with the very latest radar and electronic equipment and represented a huge leap forward in capability when compared to the aircraft it replaced. Up to 600 low-flying aircraft and surface contacts can be monitored by its AN/APY 2 surveillance radar and information is transmitted to ground and ship-based units using a wide variety of secure digital data links. Wing-tip pods containing passive sensors are also fitted. NATO and RAF aircraft also now have the new Joint Tactical Information Distribution System (JTIDS) which allows real-time data transfer between the Sentry and intercepting aircraft such as Tornado F3s and American F-15 Eagle fighters. During Operation Allied Force in the former Yugoslavia, RAF Sentrys operated from Aviano in Italy providing Airborne Command, Communication and Control (ABCCC) facilities for the allied forces involved. Since then, the aircraft have been in support of every theatre where NATO or British forces have been deployed, and are still operating in Afghanistan as part of the support forces for Operation Oracle in 2002.

Join the GlobalSecurity.org mailing list

Page last modified: 11-07-2011 03:08:09 ZULU