591 Signals Unit
591 Signals Unit (SU)
591 Signals Unit (SU) was formed at RAF Wythall, near Birmingham on 1 Jun 1952 and soon moved to RAF Medmenham near the River Thames. It was at this location next to the river that the idea of the Unit’s crest was born. The crest features a Kingfisher, and just as the Kingfisher watches over the river, 591 SU maintains watch over the integrity and security of RAF communications.
This approach is reflected in the Unit’s motto: Vigilanter – Watchfulness.
591 SU moved to Digby in 1955 and has been monitoring RAF communications security ever since. The unit acquired another capability in 1991 when the RAF’s Electrical Security Test teams transferred their operations following the dissolution of RAF Support Command. 591 SU has became the centre for ground TEMPEST testing activities. Furthermore, the team was broadened to undertake Limited Electronic Sweeps for Clandestine Eavesdropping Devices, a role that it now conducts world-wide.
As the information systems have become ever more crucial to the operation of the RAF, 591 SU has further evolved in the last decade. The Unit now has the capability to conduct a wide range of computer security tasks on all computer systems throughout the RAF, establishing a range of defensive measures to protect the information on individual systems and major network systems.
In the current era of expeditionary air operations, 591 SU personnel have increasingly been deployed to Out-of-Area locations to perform a range of tasks in support of air operations. In recognition of the deployed operational role, in July 2000, 591 SU was transferred to Strike Command and became an Air Combat Support Unit (ACSU) within the Air Warfare Centre. The emphasis therefore is now upon 591 SU personnel conducting their activities in deployed operations providing a Defence Information Operations capability to Operational Commanders in Out-of-Area locations.