RAF Boulmer

RAF Boulmer is a Royal Air Force station located near Alnwick in Northumberland, England. The current site was built in 1953, replacing an original decoy airfield established in 1940 which operated until 1945. The station's motto is 'Semper in exubitu vigilans' (Always the Vigilant Sentry).

During the Cold War, RAF Boulmer was established as a Ground-controlled interception (GCI) station as part of the ROTOR plan, opening in 1953 with an underground operations room (R3 bunker). It became fully operational in September 1954 and was designated a Group Control Centre in 1957. Upgrades included the Type 84 Surveillance radar in 1958. From 1971, it hosted Border Radar, a joint military/civil air traffic control facility, which closed in the late 1980s. By 1974, it had evolved into a Sector Operations Centre (SOC) and Control and Reporting Centre (CRC). From 1978 until 2015, it also served as a search and rescue station, initially with Westland Whirlwind and later Westland Sea King helicopters.

The R3 bunker was upgraded to an R3A in 1982. In 1990, the School of Fighter Control (later School of Aerospace Battle Management) moved to Boulmer, remaining until 2019. No. 1 Air Control Centre (No 1 ACC) reformed at RAF Boulmer in 1994, providing deployable air command and control capability. A major refurbishment of the underground bunker and installation of new equipment occurred in 2002 as part of the UKADGE Capability Maintenance Programme, with the first phase declared operational in 2004. In 2004, RAF Boulmer's NATO Control and Reporting Centre (CRC) took over all air defence functions from RAF Buchan and RAF Neatishead.

Despite an announcement in 2004 that the station would close by 2012, a 2008 study concluded that RAF Boulmer should be retained as the ASACS (Air Surveillance and Control System) hub, ensuring its continued operation. In 2021, Boulmer's Control and Reporting Centre (CRC) was allocated the No. 19 Squadron number plate.

Currently, RAF Boulmer is home to the Aerospace Surveillance and Control System (ASACS) Force Command, Control and Reporting Centre (CRC) Boulmer, No. 1 Air Control Centre, No. 19 Squadron (operating the CRC), No. 20 Squadron (ASACS Operational Conversion Unit), and No.144 Signals Unit (ASACS engineering support). Its mission is to 'generate and sustain an operationally agile air command and control capability,' focusing on homeland defence of the UK and supporting deployed operations worldwide. The CRC, named Hotspur, compiles a Recognised Air Picture within NATO Air Policing Area 1 and provides tactical control of the Quick Reaction Alert Force, operating 24/7. The station also houses the ASACS Force Resource Management Hub and a Support Wing. The site does not have operational runways for aircraft, serving primarily as a ground-based command and control facility.