The Russian Air Force has adopted an increasingly assertive posture regarding the UK as illustrated by frequent flights of its strategic bombers close to UK airspace. (UK MOD)

For 24 hours per day, 365 days per year, the United Kingdom Air Surveillance and Control System (UKASACS) watches the skies of the United Kingdom for suspicious activity. Yet plans are afoot to replace the UKASACS with a new system.

Official information notes that the UKASACS Force Command is located at RAF Boulmer in northeast England. Subordinate to the Force Command is the UKASACS Control and Reporting Centre (CRC), collocated at RAF Boulmer, which federates ground-based air surveillance radar, naval surveillance radar and airborne surveillance radar to form a Recognised Air Picture (RAP) covering the North Atlantic Treaty Organisation’s (NATO) Air Policing Area-1 which, alongside the UK, open sources note, also includes Norwegian and Icelandic airspace. The CRC, sources continue, also exercises control over the RAF’s Quick Reaction Alert (QRA) fighters tasked with responding to any incursion of UK airspace, or to any aircraft deemed to be acting suspiciously within it. Recently QRAs have been fulfilled by RAF Eurofighter Typhoon-FGR4 fighters, at least two of which are continually held at readiness, fully-fuelled with a mixed weapons load of four MBDA ASRAAM (Advanced Short Range Air-to-Air Missile) infrared-guided Air-to-Air Missiles (AAMs) and the same number of Raytheon AIM-120 AMRAAM (Advanced Medium Air-to-Air Missile) active radar homing AAMs.

The CRC forms the RAP by federating radar imagery from so-called Remote Radar Heads (RRHs). These are reportedly located at RRH Benbecula in the Outer Hebrides islands, off the northwest coast of Scotland; RRH Buchan on the northeast coast of Scotland; RRH Brizlee Wood, on the coast of northeast England; RRH Staxton Wold and RRH Neatishead; both on the east coast of England; and RRH Portreath, close to the most south-westerly point of England. These RRHs house a range of radars including the Lockheed Martin Type-92 (RRH Benbecula and RRH Buchan) and the Lockheed Martin AN/TPS-77 (RRH Staxton Wold, RHH Brizlee Wood and RRH Neatishead) and BAE Systems AR-327 Commander (RRH Portreath). 

Typhoon-FGR4 fighter
Typhoon-FGR4 fighters remain on QRA ready to respond to potential threats to UK airspace. These aircraft are usually equipped with ASRAAM and AIM-120 missiles. (UK MOD)

According to open sources, the Type-92 has a design very similar to the firm’s AN/FPS-117 L-band (1.215-1.4GHz) radar which has a reported surveillance range of circa of up to 250 nautical miles/nm (463.0 kilometres/km). In terms of altitude, the radar can cover an altitude of up to 114,829.4 feet/ft (35000km). Regarding specification, the AN/TPS-77 shares much of the AN/FPS-117’s performance characteristics, with the exception that the AN/TPS-77 has been designed to be transportable, although it is used as a fixed-site radar in the UK. It is interesting to note that the UK Ministry of Defence (MOD) procured the AN/TPS-77 which were installed from 2011 and which are now all operational, so as to mitigate the potential radar clutter which can be triggered by the spinning blades of wind turbines. The UK has established a number of offshore wind farms on the eastern coast of England, hence the need to deploy radars which are resistant to this resulting radar clutter. Finally, the AR-327 Commander is an S-band (2.3-2.5/2.7-3.7GHz) radar has a reported maximum range of 253.8nm (470km) and altitude of 100,000ft (30480m).

In addition to the radar imagery which is generated by these systems to form the RAP, the UKASACS can also receive additional imagery from the RAF’s fleet of seven Boeing Sentry AEW.1 airborne early warning aircraft equipped as they are with the Northrop Grumman AN/APY-2 airborne surveillance S-band radar which provides a range of 216nm (400km). This is in addition to the RAF’s Raytheon AN/FPS-132 Ultra High Frequency (300 Megahertz to three gigahertz) ballistic missile early warning radar located at RAF Fylingdales in northeast England. This radar has a range of circa 3000 nautical miles (5556 kilometres). Beyond the Sentry AEW.1 fleet and the AN/FPS-132 radar. The RAF is able to draw upon radar imagery provided by the UK’s National Air Traffic Services (NATS) which provides air traffic services across the UK.

Sentry AEW.1 aircraft
The RAF’s Sentry AEW.1 aircraft form an important part of the overall UK air defence posture, helping to plug gaps in radar coverage and to provide additional radar imagery for the UKASACS. (UK MOD)

According to official RAF literature, RAF Boulmer either detects an aircraft behaving suspiciously using its own RRHs or from NATS. A decision is then taken to scramble the Typhoon-FGR4s on QRA. The airspace around the suspicious aircraft is then cleared by the NATS, and RAF Boulmer will control the interception of the aircraft. The publication adds that the ultimate command as to whether to shoot down an aircraft which has remained unresponsive to demands for it to cease its activity rests with the UK Prime Minister. In terms of hardware and software, IBM provided the RAF with the UKASACS Command and Control System (UCCS) which, according to official UK Ministry of Defence documentation, provides the ASACS air surveillance and air command and control capabilities via workstations, software, servers and networking equipment. Both RAF Boulmer and RAF Scampton in Lincolnshire, also in eastern England which provides a backup facility to the site at Boulmer, host 41 UCCS workstations at each of these CRCs. The reason for the two CRCs, according to an MOD document is: “so that the routine air policing role can be run by either centre giving dual resilience to the system.” Also located at each CRC is the Flight Plan Dissemination System (FPDS) which is used to populate the UCCS with flight plan information from civilian ATM.

AN/FPS-117 radar
Shown here is an AN/FPS-117 radar, upon which the AN/TPS-77’s design is closely based. The example in this picture is operated by the Royal Australian Air Force. (UK MOD)

The overall UKASACS architecture has been modernised via the Project CERBERUS initiative. Official dubbed by MOD literature as: “an obsolescence driven mid-life technical refresh and life extension to the data handling, processing and display component of UCCS,” the CERBERUS effort was led by IBM. Further improvements are now occurring for the UKASACS in the form of the Project GUARDIAN initiative. An undated MOD document provided some important information regarding the intentions of the Project GUARDIAN undertaking. While much of the document is redacted, it is possible to gain some insight into its scope. Whereas the Project CERBERUS effort sought to enhance capabilities of the UKASACS, for all intents and purposes, the latter initiative, according to the document, “will replace the current Air C2 (Command and Control system) installed at (redacted).” While the document omits the locations of the Air C2 system to be replaced, it is reasonable to assume that this refers to the UCCSs at RAF Boulmer and RAF Scampton. The document continues that, presently, the existing UKASACS architecture employs a: “dedicated voice communications system that connects to the UK defence network of radars and radios,” and that Project GUARDIAN: “will deliver the new capabilities of (redacted).” This could mean that the new communications architecture which will comprise Project GUARDIAN will include Voice Over Internet Protocol communications. Finally, the Project GUARDIAN architecture: “will include the exchange of radar track data between UK command sites and NATO (North Atlantic Treaty Organisation) Command sites in Europe.” Currently, the UK is thought to share the RAP generated by the UKASACS with NATO’s Combined Air Operations Centre at Uedem in central Germany.

This latter point is particularly important. Much of the NATO’s European membership is involved in the Air Command and Control System (ACCS) initiative which is being led by the ThalesRaytheonSystems consortium. Put simply, the ACCS initiative is an ambitious programme to replace several disparate Air C2 systems used both to safeguard air sovereignty, and for the planning and execution of air operations, with a scalable fixed and deployable hardware and software architecture across the participating nations. This will not only standardise the equipment being used, but help the alliance develop a single ‘Super-RAP’ depicting the airspace over NATO’s European membership. The inference in the MOD document is that, while the UK has chosen not to participate in the ACCS initiative (see below), it does plan to include mechanisms to share its national RAP with NATO to contribute to the Super-RAP.

In terms of time scales, the MOD document stated that the ministry is expected to enact its so-called ‘Main Gate’ approval for Project GUARDIAN in the May/June timeframe. Main Gate approval is MOD terminology for when the UK government takes the decision to commit the main part of its investment to bring the programme to fruition. Though as the discussion below illustrates, these plans could now be in a state of flux. The document further informs that the Project GUARDIAN architecture will interoperate the current communications systems used by UKASACS, including its Tactical Data Links (TDLs) described in detail below.

Moreover, the UKASACS’ predecessor, IUKADGE (Improved UK Air Defence Ground Environment) system which entered service on 1 June 1993 was known to use Marconi’s UNITER digital telephone system for its ground-to-ground communications. An undated document published by British Telecom, still hosted on the company’s website, advertising the firm’s Defence Fixed Telecommunications Service, stated that the UNITER defence secure voice network remains in service. Additional publicly available RAF documents noted that the RAF’s Fixed Telecommunications System (FTS) forms a vital part of the UKASACS architecture and provides secure and unsecured voice communications, recorded messages in the form of written orders or signals across the UK’s Defence Communications Network and the transfer of data. The RAF also “ensures good communications between all agencies and authorities” who maybe involved in an interception being led by the UKASACS. As noted above, this could include the UK NATS and the UK prime minister’s office. Two components form the FTS, a system known as BOXER and UNITER. Documents obtained by Armada note that the BOXER network uses fibre optic, satellite and microwave communications links which entered service with the RAF in 1996, and which are owned by the RAF. UNITER, meanwhile, constitutes the switching and terminal equipment enabling the user to communicate with a receiver.

Meanwhile, a number of tactical data links are employed to connect platforms such as the RAF’s Typhoon-FGR4 fighters on QRA to the UKASACS, not least of which is the Link-16 TDL. Link-16 is a NATO TDL standard that provides secure voice and data communications across a frequency range of 969 Megahertz/MHz to 1.2 Gigahertz/GHz. It enables radar track, and other tactical information, to be shared between these aircraft and the UKASACS. Link-16 is also used by the RAF’s Sentry AEW.1 aircraft allowing the similar exchange of tactical information. The Royal Navy can share similar data using NATO’s Link-11 TDL. Link-11 is used for the exchange of similar tactical information across High Frequency (HF) and Ultra High Frequency (UHF) communications. Whereas Link-16 is largely used to support air operations, Link-11 is mostly used in the naval domain. The asset of using Link-11 is that it allows platforms such as the Royal Navy’s ‘Daring’ class destroyers, which are armed with the MBDA Aster-15/30 active radar homing surface-to-air missiles, to enhance the UK’s air defence by contributing track information derived from the ship’s BAE Systems’ SAMPSON S-band and Thales S1850M L-band naval surveillance radars.

Royal Navy’s ‘Darling’ class destroyers
Alongside RAF aircraft, the Royal Navy’s ‘Darling’ class destroyers can feed radar track information into the UKASACS via their Link-11 and Link-16 TDLs. (UK MOD)

The Crunch

As noted above, the UK MOD was originally planning to make its ‘Main Gate’ decision vis-à-vis the Project GUARDIAN procurement in May/June 2017. However, on 18th May, UK Prime Minister Theresa May announced a general election to be held on 8th June. This may well suspend the MOD’s decision on proceeding with the Project GUARDIAN procurement until the political landscape is clear after the election. Secondly, the government has entered a period of purdah until after the election, meaning that the author’s requests to the MOD for an update regarding the current status and future plans regarding the Project GUARDIAN initiative have remained unanswered.

According to Douglas Barrie, senior fellow for military aerospace at the International Institute for Strategic Studies, a London-based think tank, the MOD and RAF will need to take a number of strategic factors into account as they evolve the Project GUARDIAN architecture: “Ten years ago, the design could have comprised a fairly benign system designed to protect UK airspace,” he stated. However, Russia has now moved from being an “irascible neighbour to a strategic competitor.” Mr. Barrie stated that this strategic change was hallmarked by Russian President Vladimir Putin’s speech during the February 2007 Munich Security Conference, during which Mr. Putin railed against a perceived domination of the international system by the United States and its allies, declaring that: “It is world in which there is one master, one sovereign.” At the operational level for the UK, and for NATO in general, this emergence of Russia as a strategic competitor has translated into regular flights by Russian Air Force aircraft close to UK airspace, with Typhoon-FGR4 aircraft being scrambled from Coningsby airbase in eastern England in early February to intercept two Russian Air Force Tupolev Tu-160M/M2 strategic bombers thought to be flying close to UK airspace. Mr. Barrie continued that the UK once again faces Russia as a potential adversary much as it did during the Cold War, and that this could require the Project GUARDIAN system to be capable of performing: “surveillance against a range of platforms which include not only inhabited aircraft, but also air-launched cruise missiles, and platforms with a low radar cross section such as fifth-generation fighter aircraft.”

The Russian Air Force
The Russian Air Force has adopted an increasingly assertive posture regarding the UK as illustrated by frequent flights of its strategic bombers close to UK airspace. (UK MOD)

Cost is a second consideration for the realisation of the Project Guardian architecture. The UK was originally a partner in the ACCS initiative (see above) however late last decade the country suspended its involvement. According to a highly placed source close to the programme, the suspension occurred because the UK did not feel that the ACCS architecture, at that stage of development, met the UK’s safety requirements. Despite this, the source continued that the RAF has remained very interested in the ACCS, particularly the theatre missile defence capability which forms part of the overall ACCS architecture. That said UK procurement officials have ruled out the procurement of the ACCS architecture and Armada’s source continues that the UK MOD is strongly expected to award the Project GUARDIAN work to the “incumbent supplier,” in this case IBM which supplied the UKASACS architecture.

Nevertheless, the decision not to proceed with acquiring ACCS could impose a financial penalty on the UK. Armada’s source continued that, as an original partner, the UK remains committed to sharing the funding of the ACCS realisation, yet in addition to this, it will now have to also procure the Project GUARDIAN architecture, effectively paying twice for a new Air C2 system. This could place additional pressure on the UK defence budget following media reports in late April that the UK’s Public Accounts Committee, a parliamentary committee that scrutinises the value for money of UK government spending, that the MOD’s ten year procurement programme which commenced in 2012 risks becoming unaffordable. In addition, the UK may suffer financial uncertainty and the possibility of the value of Sterling weakening further as the country prepares to leave the European Union in 2019. This could result in lower fiscal revenues for the government over the 2017 to 2019 timescale, possibly making Project GUARDIAN a hostage to financial fortunes against a backdrop of continued strategic uncertainty.

by Thomas Withington