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A Brief History of the Genesis and Evolution of the Fighter Control Branch

by Tim Willbond


To understand the genesis of the Fighter Control Branch and its long and intimate association with RAF Bentley Priory it is necessary to look back to the war to end all wars between 1914 and 1918. The first world war saw many innovations which were to change the nature of warfare; one of the most worrying was the attacks on civilian targets on the mainland of Great Britain from the air by airships and the first generation of long range bombers. The era of total war had been born.

Figure 1. General Ashmore

Figure 1. General Ashmore

The daylight attacks on London had a profound effect and the public outcry led to the formation of Prime Minister's Committee on Air Organisation and Home Defence against Air Raids. The result was the creation of the London Air Defence Area, covering in fact the whole of the South East of England, and under the unified control of an airman. To command it a Brigadier General Edward Ashmore was brought back from France where he had been commanding a Royal Flying Corps Brigade. He was an inspired choice because he had both experience as a Royal Artillery Officer and as an airman. Ashmore was later to observe that the great principle of air defence was that although aeroplanes were the first line of defence they were ineffective unless there was an organisation for command and control to direct the air battle.

The challenge faced by General Ashmore in setting up an organisation to coordinate and control air defence was common to all aspects of warfare albeit that the challenge was compounded by two factors which were the need to think in three dimensions and the speed of operation necessary to counter an enemy attack.

The process of decision-making in command and control is often expressed in military terms as the OODA loop. This stands for Observe, Orientate, Decide and Act and in terms of the problem of creating an air defence system translates into the need to detect the attacking aircraft at ranges that allow for interception before they reach their bomb release points; the need to determine height, speed, direction, numbers and to confirm they are hostile and not friendly; then to decide upon a suitable response and finally to order and control the response.

The Early Years

The work that General Ashmore undertook provided the foundation for the system of air defence which enabled victory in the Battle of Britain in 1940. The system incorporated many of the elements that were present in 1940 including a system of coordinating reports, plotting them on a central plotting table and passing information to Anti-Aircraft Artillery and orders to leaders of formations of fighters. The sensors were human observers on the coast and inland who reported contacts to a sub control which in turn reported to central control at the Horse Guards. Although he never commanded the Royal Observer Corps per se General Ashmore is credited with their formation. The ‘observers’ were limited in that they could not see far out over the sea approaches to the UK and were severely hampered when there was a lot of cloud and they could not operate at night.

The invention of radar in 1935 and the improvements to, and wider deployment of, radio telephony were the catalyst for the creation of what became the Fighter Control Specialisation. Air Chief Marshal Dowding, using the principles set down by Ashmore, was the architect of a system of air defence which incorporated radar and other technological advances and a method for the command and control of the new generation of eight gun fighters. The system became known as the 'Dowding System'.

Figure 2. The 11 Group Filter Room

Figure 2. The 11 Group Filter Room

The main aims of the system were to provide a recognised air picture and then to control a timely response to air attacks which included both the aircraft of Fighter Command and the Anti -Aircraft Artillery guns under the Command of General Pile and the Operational Command of Air Chief Marshal Dowding. Returning to the OODA loop, in 1940 the ‘Dowding System's’ ability to observe was provided by a chain of radars along the East and South coasts looking over the sea approaches to the UK whilst overland the eyes of the Observer Corps were the only method of tracking enemy aircraft. The ‘Orientation’ was provided principally by a filter room at Bentley Priory . The principle of command and control that Dowding espoused was that of centralised command and decentralised control. This meant that the tactical control of the battle was exercised by Group Commanders from their group headquarters at 10 Group in the South West, 11 Group in the South East, 12 Group covering the Midlands and East Anglia and 13 Group covering the North. Tactical control of weapons was delegated downwards and in the case of the fighters this fell to the Sector Controllers operating from sector airfields within group areas. The Groups where the decision engine and the ‘act’ part of the system was the control of the weapons systems during a battle which was undertaken by the sectors. The capability of the system to provide warning of air attack in sufficient time to allow targeted personnel and equipment to be moved out of harm's way and to implement deception measures also made a valuable contribution to the defensive effort.

Now, in examining the genesis of the Fighter Control specialisation it is important to understand that much of the system was new and no previous personnel organisation with training and career structures was in place. In the early days the system from radar to filter room was manned by hand-picked enthusiasts who were usually scientists; however, with the rapid expansion of the system the radar chain was initially manned by technical trades and clerks special duties; the operations rooms at HQ Fighter Command, Groups and Sectors were initially staffed by signals personnel but after 1936 they were staffed by pilots and the filter room was manned by clerks special duties as plotters and SNCOs drawn from all trades as ‘filterers’. The filter room was both a pivotal and critical point in the system but its product was deteriorating rather than improving with experience. An analysis revealed that the job of ‘filterer’ was the key to success and on 19th February 1940 approval was given to recruit officers, usually with a degree in a science or mathematics subject, as filter officers. The first 15 Officers especially selected and trained for the task were appointed on 10 June 1940. Arguably this is effectively the birth of the Fighter Control specialisation.

Figure 3. GCI Operations Room

Figure 3. GCI Operations Room

The next step in the genesis of the Fighter Control specialisation came with the creation of Ground Controlled Interception (GCI) units. The problem was that attacks that had passed through the seaward-looking radar cover and proceeded overland in poor weather or at night could not be tracked. The development of radars that rotated to scan 360 degrees and the Plan Position Indicator (PPI) which enabled an aircraft's position and movement to be viewed in plan position meant that aircraft could be tracked overland and it also provided an accurate basis for interception. Initially six units were commissioned and unlike the radar chain, which was under the command of 60 Group of Fighter Command, they were attached to sector stations. Once again it was deemed sensible to redeploy sector controllers from the sector stations to act as interception controllers; this concept met with varied success because, as the years have shown, the skills needed for interception control are specialised. However, the immediate impact and success of GCI units led to a very rapid expansion and there were simply not enough ‘sector controllers’ available and so it became necessary to train ab initio controllers. Hence, the second strand of the specialisation was born.

The specialisation has always championed the role of women in an operational capacity and WAAFs were commissioned in 1941 to take over filterer and filter officers' jobs to release the men for overseas deployment. This practice carried on after the war with women undertaking tasks across the whole specialisation. The first operational WRAF Air Commodore was a Fighter Controller.

Post World War II Developments

From the foregoing it can be seen that in the early days the Fighter Control organisation had two distinct tasks: first the management of systems and analytical processes to create a fully recognised air picture; secondly, the control of fighters to counter air threats and in this context, specifically, interception control. The organisation was often referred to as the Control and Reporting system. The Sectors and Groups still managed the overall tactical battle in their respective areas.

There was a most significant shift of responsibilities in 1968 when Strike Command was born. Prior to this Commands in the UK had been functionally orientated and groups geographically organised. However, the Strike Command reorganisation saw single functionally based Groups replace Commands. This started a process that seems to have been more de facto than de jure, which led to the tactical management responsibilities which had been vested in Sector Commanders at sector airfields being devolved to ‘Sector Radar Stations’. In addition, most of the battle management functions hitherto exercised by group commanders were also flowed downwards to Sector Commanders. This was the effective birth of tactical battle management as another skill that now fell to the Fighter Control specialisation to deliver.

The Cold War