The Defence High Frequency Communications Service or the DHFCS is a British military beyond line-of-sight communication system operated by the Ministry of Defence (MOD) and used predominately by the UK Armed Forces, as well as other authorised users. The system operates from six transmitting and receiving sites across the United Kingdom and is controlled from a network control centre located at Forest Moor in North Yorkshire and a backup site at Kinloss Barracks in Moray. Overseas sites are located in Ascension Island, Cyprus and Falkland Islands. In 2003 VT Merlin Communications (now Babcock International Group) were awarded the contract to operate the system for a period of fifteen years on behalf of the Ministry of Defence. The system is to be replaced by the Defence Strategic Radio Service (DSRS) also operated by Babcock[1]
History
Masts at DHFCS Forest Moor, North Yorkshire.
Legacy systems
Prior to the creation of the DHFCS, the Royal Air Force (RAF) and Royal Navy (RN) operated their own independent high frequency (HF) communications systems. The RAF's Strike Command Integrated Communications System (STCICS), later known as Terrestrial Air Sea Communications (TASCOMM), operated from six sites within the UK whilst the RN system had twelve sites.[2] The systems overlapped in their capabilities whilst simultaneously having gaps in overall capability, high running costs, lack of flexibility and neither were used to their full capacity.[3]
Through the rationalisation of sites, twelve sites (four RAF, seven RN and a joint site in Gibraltar) were closed between 2003 and 2006. Many sites were used for other military purposes with the sites at Bampton Castle, Chelveston and Milltown being the only sites which closed entirely.
Closed legacy system sites
UK Military High Frequency Transmitter, Receiver and Control Centre Sites Closed as Part of DHFCS Rationalisation
Defence High Frequency Communications Service (DHFCS) sites within the United Kingdom. Red location markers represent HF receiving sites, blue markers are HF transmitting sites and green markers LF sites.
The service allows real-time strategic communications between users which comprise ground stations, submarines, surface vessels, fixed wing aircraft and helicopters.[9]
Structure and operation
The DHFCS was declared operational in March 2008. Within the UK, the system is divided into three stations of paired transmitter and receiver sites. 'UK North' comprises sites at Kinloss Barracks and Crimond in north east Scotland, 'UK Middle' at Forest Moor and Inskip in northern England and 'UK South' at St. Eval and Penhale Sands in south west England. Three overseas stations, with two sites each, are located in Cyprus, Ascension Island and the Falkland Islands.[10]
The system was originally operated from a network control station (NCS) located at Forest Moor, with an alternate network control station (ANCS) at Kinloss which could be used in the event that Forest Moor station was unavailable. Split site working was introduced in 2011 which allows both the Forest Moor NCS and Kinloss ANCS to control 50% of the network, increasing resilience and recovery time in the event of a loss of service and minimising potential network unavailability.[11]
Sites at Anthorn (Formerly HMS Nuthatch) and Skelton in northern England provide a Very Low Frequency (VLF) transmitting capability which is used to send communications to submerged submarines. Due to the low frequencies involved submarines can only receive VLF communications and do not carry VLF transmission aerials. Therefore, there is no requirement for land-based receiver sites as communications are one way.
The DHFCS is known to have the following capabilities.[12]
