Skip to main content

Controlling the Battle of Britain: the Dowding System explained

Controlling the Battle of Britain: the Dowding System explained

The existence of a highly sophisticated integrated command and control system proved critical to the success of the Royal Air Force in the Battle of Britain. Here we take a brief look at how it worked…

Organising Britain’s air defences

 In the summer of 1940 Britain was in a desperate situation, facing the real possibility of invasion by Germany. Much depended on the Royal Air Force denying the Germans the air superiority they needed to invade successfully. 

What happened next is of course the stuff of legend: indeed the exploits of ‘The Few’ during the Battle of Britain has entered British folklore. Despite concerted German attempts to destroy the British fighters in the air and on the ground the RAF ultimately gained the upper hand in what was effectively a battle of attrition, and the Germans were in due course forced to postpone their invasion plans indefinitely.  

Obviously the bravery and professionalism of the RAF’s personnel - both the air and on the ground - where key factors in its success, as was the availability of two modern fighter aircraft, the Hawker Hurricane and the Supermarine Spitfire. And new military technology, in the form of Radar (known then as Radio Direction Finding), was also crucial too. 

But one other critical factor should not be overlooked - effective organisation. 

In the run up to war, the British had set up an integrated command and control system which allowed them to make best use of their limited fighter resources during the Battle of Britain. Without this system the outcome of the Battle of Britain could well have been very different.  

The need for such a system was graphically illustrated in 1934 during large-scale RAF exercises when very poor interception rates were achieved during mock bomber attacks on London.  Such tests showed that it was very difficult to get useful information to the defending fighter pilots quickly enough for them to use it. 

When Hugh Dowding became Air Officer Commanding-in-Chief of Fighter Command on its creation in 1936, he set about resolving the problem.  Dowding had already in fact made a very significant intervention just the year before, when as Air Member for Supply and Research, he approved funding for the development of Radar.      

The Dowding System’  

Dowding established a clear operational hierarchy within Fighter Command. The idea was that information would pass down the chain of command and, in the process, would only be sent to where it was actually relevant. The rapid flow of information was made possible by a dedicated telephone network, the lines buried deep underground.   

At the top of this hierarchy was ‘Command’, located at Fighter Command Headquarters at Bentley Priory, Stanmore, Middlesex. Command maintained an overview of the whole battle situation right across the country. 

Information on enemy aircraft movements sent from radar stations and Observer Corps centres, along with information on the positions of friendly aircraft from RAF direction finding stations, would arrive at Fighter Command HQ, where it was all ‘filtered’ to produce a coherent picture of developing air raids.  

Coloured markers were used to indicate the position, height and strength of aircraft formations on the General Situation Map table in the Operations Room. These markers were moved around the map manually by RAF and Women’s Auxillary Air Force ‘plotters’ using long magnetic rods. 

Looking down on this map from his gallery position, the Duty Controller was able to assign each incoming raid to the appropriate ‘Group’. 

During the Battle of Britain there were five operational ‘Groups’ in Fighter Command, each assigned a particular region of the country to defend.  So, for example, No 11 Group was responsible for defending the South East of England.  ‘Groups’ formed the next level in the command and control hierarchy and were responsible for controlling all the air battles that took place in the airspace they covered.

Each Group had its own Operations Room with its own plotting table, showing the area of the country for which it was responsible. There would also be a series of blackboards and electrically illuminated indicator boards showing the current strength and status of each squadron within the Group. Group Commanders would select which squadrons should engage enemy aircraft encroaching on their airspace.         

Each Group was split into several ‘Sectors’, directly overseeing fighter squadron operations. Sectors were the lowest command level in the hierarchy. The Sector Operations Rooms would receive  information relevant to their areas from Group, and this information would be plotted on their own plotting table maps. 

It was the Sectors that were responsible for direct communication with pilots, scrambling the squadrons under their control in response to instructions from Group and providing vectoring information to the pilots once they were airborne. 

To ensure a co-ordinated defensive response to air raids, Fighter Command also controlled the anti-aircraft guns and searchlights operated by the Army and the barrage balloons flown by RAF Balloon Command. 

Although the Germans were aware of the British use of radar, at the time they did not appreciate how important Dowding’s command and control system was for making best use of the information this new technology was providing. However, their attacks on RAF air bases, with the intention of destroying British fighters on the ground, did pose a threat to the system as  

Sector Operations Rooms were, as a rule, based at airfields. 

Indeed, the Sector Operations Room at Biggin Hill was destroyed in one such raid. To counter the threat, emergency operations rooms were subsequently set up locally off-site.  

Making the most of ‘The Few’

The ‘Dowding System’ (as it has become known in more recent times) proved to be very successful. By making it possible to rapidly process and distribute the vast amount of information provided by radar and ground-based observers, the system maximised the usefulness of that information - which in turn enhanced the effectiveness of Britain’s air defences. 

With access to accurate and timely information, the British fighters could operate very efficiently - flying out from their bases directly to their targets, engaging in combat and then returning home to refuel and re-arm ready for the next raid. There was no need to rely on standing patrols, a tactic that would have needed many more fighters than the RAF possessed to be anywhere near as effective. 

By the end of the Battle of Britain interception rates of over 90% were not uncommon, whereas during the preceding Battle of France when no such control system had been available the RAF’s interception rates had typically been 30%.

Tracing the story today

Today Bentley Priory is a museum telling the story of Hugh Dowding and the Battle of Britain. The exhibition includes recreations of the ‘Filter Room’ (where the vital information from radar stations and observer posts was first received and processed) and the Fighter Command HQ Control Room. See:

Not very far from Bentley Priory, on the former site of RAF Uxbridge, it is possible to take a guided tour of the Grade II listed underground bunker from where No.11 Group controlled its wartime operations. See:

And the sights and sounds of an airfield Sector Operations Room can be experienced at IWM Duxford:

Key facts

  •  TheBritish radar stations in use during the Battle of Britain were located near the coast and could only ‘see’ out to sea. Once raiders had flown inland, the Dowding System was reliant on visual spotting information provided by the Observer Corps.
  • The Dowding System was hindered by the widespread use in RAF fighters of High Frequency (HF) radios which had a relatively short range and were prone to interference, although the original intention had been to equip all  aircraft with Very High Frequency (VHF) radios by 1940.
  • The summer of 1940 was unusually sunny which was something of a double-edged sword: the good weather made more German raids possible which put the RAF under greater pressure, but clear skies also made it easier for the Observer Corps to pinpoint the raiders accurately from the ground.  
  • The Dowding system worked less well against high flying raids or in cloudy conditions when ground spotting was difficult. To counter this problem, a high altitude special reconnaissance flight was set up to patrol routes often used by German raiders, equipped with VHF radios to alert No.11 Group Headquarters.  
  • Although the battle command decisions were made by RAF officers, the smooth and efficient operation of the radar and signals stations and the Operations Rooms relied very heavily on the skill, expertise and bravery of Women’s Auxillary Airforce (WAAF) personnel.  
  • Fighter Command Headquarters at Bentley Priory was also responsible for operating the National Air Raid Warning System. There were 130 individual ‘Warning Districts’ across Britain to which warnings could be issued via telephone.   

For more information on the Dowding System, check out the Haynes Battle of Britain Operations Manual