The inspiration for this section is from Peter Flint's book
for his study of AVM Lord Hugh Dowding and Fighter Commands HQ at Bentley Priory

Battle of Britain - 1940 
Dowding & Bentley Priory
the closing words on Dowding's statue
Whenever we think of the Battle of Britain, our thoughts turn to Fighter Command, if we thought of Fighter Command, our thoughts would then turn to Air Chief Marshal Lord Hugh Dowding, and if we thought of Hugh Dowding we would then think of the nerve centre of Fighter Command, Bentley Priory.

It was in July 1936, that during a complete reorganisation of the Royal Air Force, the task of creating an all new section fell to Air Marshal Sir Hugh Caswell Tremenhere Dowding KCB. This section was to be known as Fighter Command. Dowding had had an impeccable career that had originated in 1900 as an Army Subaltern with the Royal Garrison Artillery and it continued with the Royal Flying Corps during the First World War. He had commanded Fighting Area in the earlier Air Defence of Great Britain (ADGB) organisation in 1929-30 and thereafter for six years he was employed as Air Member for Research and Development on the Air Council. He was a man who had faith in the Radio Direction Finding(RDF) later to become known as Radar of which he had great influence on its future development.

Dowding was a man of strong character with a mind capable of deep thought and foresight, and had very positive views on how his new Command and the air defence system should develop. He was of a naturally reserved nature with a disinclination towards most forms of socialising; his seemingly humourless, often grumpy image portrayed to those not of close acquaintance, plus a facility of quick acid comment, gave him enemies and a reputation for being difficult. He sought the favour of no-one. From his early service days the nickname 'Stuffy' endured.
Peter Flint Dowding and Headquarters Fighter Command pp2

Dowding was given Bentley Priory as his headquarters. It was to be the nerve centre of Fighter Command. It was back in March 1926 that the Royal Air Force acquired a rather dilapidated house and land in Stanmore that is now known as Bentley Priory. On 26 May it became Headquarters of Inland Area that administered a number of air force home establishments and was under the command of Air Vice-marshal Tom Webb-Bowen CB, CMG. But before this, the 'Priory' had an interesting, yet chequered history. Originally, a rather insignificant small house that was owned by a Mr James Duberly it had been renovated, with the addition of many additional rooms that greatly increased its size, and became a highly prestigious country estate in the possession of The Hon James John Hamilton. In 1789 as 9th Earl and First Marquis of Abercorn, he engaged the services of architect Sir John Sloane to carry out massive extensions to the house and buildings at considerable cost. Later, it was owned by builder Sir John Kelp and when a Mr Frederick Gordon took over the elegant buildings and land it was turned into a luxurious private hotel. Before much of the property was sold off it had been used as a private boarding school for young ladies before the Royal Air Force acquired it in 1936.

Prior to the official installation of Fighter Command at Bentley Priory, discussions were taking place on the functions of a Command Headquarters Operations Room would be expected to fulfil. On 10 June Dowding attended a high level meeting held to lay down the basic requirement for the room and its associated communications. It was concluded that all intelligence on aircraft in flight supplied by the various observation sources, including Radar, should be transmitted through the most direct channels to Group Headquarters and Sector airfields. It was thought that it might be necessary for the long-range readings from the proposed Radar stations on the coast to be initially transmitted direct to Bentley Priory and plotted on a large map there; maps at Groups or Sectors would basically show only the Group's area of responsibility. Reports from Secret Services sources and enemy radio interceptions would normally be of a strategic nature and, as such would be passed on to Fighter Command and not directly to Groups. The Admiralty should have a direct link with the air defence system through Fighter Command.
Peter Flint Dowding and Headquarters Fighter Command pp2-3

Prior to moving into Bentley Priory, Dowding lived and conducted his affairs from his home at Wimbledon Hill in the south west of London, and it was from here that he outlined his plans for setting up an Operations Room at the 'Priory'.
In July 1936 Dowding made his first visit to Bentley Priory, HQ of the newly created Fighter Command. Bently Priory was an old gothic house on a hill to the extreme north-west of London. It was typical of this idiosyncratic man that instead of arranging the ceremony that would normally take place, he arrived at nine-o'clock in the morning unannounced and all alone. The guard was extremely reluctant to let him through the gate but after inspecting his papers, he handed him over to the most senior man there, a sergeant from the Orderly Room. The two men wandered through the grounds and then through the empty rooms. Selecting a room with a southerly view, Dowding asked the sergeant to put his name on the door, thanked him and left.
Len Deighton Fighter p40
"The Ball Room seems to be most suitable for the purpose although this of course may not be desirable as a permanent location owing to the fact the Priory is extremely conspicuous from the air and the rooms would be very difficult to render gas proof. I do, however, wish to make a start immediately so that the delay in the production of my permanent Operations Room may be reduced to a minimum and only by immediate experiment can be determined the requirements necessary for the purpose"
Peter Flint Dowding and Headquarters Fighter Command pp4

Dowding went to say that in the centre of the Ball Room would be the main Operations Room Table that would be covered by a huge map that would cover from Edinburgh in the north to the French coast, and from the border of Wales in the west to the east of Belgium. A viewing gallery would be required along the North and West sides of the Ball Room so that it would be possible to observe the various movements that would be displayed on the map below. Also, teleprinters would have to be installed, and these would be placed in the Rotunda.

An intricate telephone and communication system would have to be installed. What was happening around the British coastline would be clearly displayed on the huge map that occupied the ballroom. Reports from the long-distance radar could possibly be received direct, and then relayed to the Groups Headquarters. Any Intelligence information would most certainly be received first at Bentley Priory and then circulated to groups and military offices. Finally, all movements of enemy and friendly bombers would be tracked and displayed on the map, but possibly for reasons of not making the map board to complicated and messy, friendly fighter movements would not be shown. A series of lights would be installed on one of the walls, and these would indicate as to the state of readiness of fighter groups.

"To me, an LAC, Air Chief Marshal Dowding lived in a different world. His personal clerk was one Corporal Custance and when he went on leave I had the privilege of being his 'stand-in'. Apart from being called upon to take down pages of shorthand upon highly secret fighter defence matters, I have little recollection of the Air Chief Marshal, except that he was stern but kind. Of the other Officers, in those days 95% were of the General Duties Branch and all were pilots, each having to perform a number of flying hours per year.
The pre-1939 RAF Officer was most emphatically an Officer and a gentleman and , as such, had Service and social obligations. The more senior ones were ex RFC or RNAS. The only time we saw any of our Officers in uniform was when they were going on a Staff visit, Armistice Day, Kings Birthday or other such occasion; normally they came to work in lounge suits. Headquarters Units were not commanded by a Commanding Officer but by a Camp Commandant and ours was one Flight Lieutenant Gearing.
Looking back, I can only say that at Bentley Priory we were an extremely happy set of people; I cannot recall any unpleasant words or deeds. Esprit-de--Corps and morale were of the highest order. In the very stable and civilised conduct of affairs in the United Kingdom at that time security was almost unnecessary, but there was always a Duty Staff Officer, a Duty Clerk, Duty Signals Personnel and an Air Ministry civilian policeman or two on duty.
LAC Jim Griffiths on Bentley Priory. Dowding and Headquarters Fighter Command/Peter Flint pp3-4
The conservatory was removed at the outbreak of WWII
Leading Aircraftman Jim Griffiths went on to say that as an LAC his weekly pay was 31/6d of which a 10/6d of that was placed in a Post Office Savings Account. He enjoyed life at Bentley Priory, and he had many memorable times playing sports, the odd dance at the NAAFI and visits to theatres and pubs. Occasionally he received weekend leave which he spent mostly with his parents although he did have a good relationship with his girlfriend. At Bentley Priory, he had his own room unlike other LAC's on station who had to live a barrack room lifestyle, and the food at Bentley was absolutely first class. There was an odd parade but there was also a lot of hard work that was generally spread over long hours.


Work on the Experimental Operations Room was sufficiently advanced by 11th December 1939, that Dowding wrote to the Air Ministry requesting the installation of GPO telephone lines. He also made mention of the intention to limit the field of experiment to a single link up with No.11 (Fighter) Group, and in so doing, concentrating effort in developing and proving a prototype component of the future organisation.
Hugh Dowding in his role as Chairman of the Home Defence Committee's Sub Committee in May 1937, which was also the date of the creation of No.12 Fighter Group, gave a lecture to members of the RAF Staff College on "Fighter Command in Home Defence". and when we look at the basis of Dowding's lecture, we are to find that his ideas and opinions were remarkably prophetic. 

Hugh Dowding first spoke about how a war would be most quickly lost and stated that this might possibly be caused by indiscriminate air attacks on London and creating panic amongst its population. As an alternative, an immediate paralysis of the food supply would have exactly the same effect and that if the country could be secured against a quick decision of this kind, then the only defeat could come from the slower process of exhaustion of equipment, personnel, food, raw materials, sea transport and other resources. He went on to state that the focal point of the machinery of Government and the main centre for the distribution of the countries food supplies would be London itself, and concluded that the most important task would therefore be the defence of London itself. The most important task therefore would be that defending London would be the most important task in the defence of Great Britain. Dowding went on to say, that if he was the dictator, then first and foremost, he would destroy the enemy's Air Force at his airfields, reserve storage depots and factories etc. 
Dowding continued: 
"There is another possible form of attack which I think deserves closer study than it has received up to the present. I refer to the attacks on our food and supply ships at sea.
He went on to say that the diversion of shipping away from the vulnerable areas of the Port of London and the Thames Estuary, to western ports be a matter of highest importance, his concern was the possibility of attacks on inland targets becoming unsustainable and that the bulk of offensive power being turned to supply ships at sea. 
He went on: 
"It seems to me that our shipping will, broadly speaking, be as open to submarine attack as it was in the last war and that it will now have to face the additional danger of attack from the air.
On attacks on London, Dowding said that the main dangers would be fire, bomb explosion and gas, and it would probably occur in that order. He considered incendiary attacks on property, that would enable the enemy to utilise for purposes of destruction be the greatest danger that the population would have to face, that a single bomber might distribute a thousand small incendiary bombs, and with a dense population as the city of London a single bomber could initiate something like a hundred small fires. 
"There is a serious danger that groups of individual fires, which are not properly dealt with, will unite and cause conflagration which will be beyond the control of any fire fighting organisation which we are likely to be able to provide." he said. 
Remember, that this was a speech that Dowding gave in 1937. 
Based on the descriptive of the speech Dowding and Headquarters Fighter Command/Peter Flint pp11-12 

Dowding had a strong interest in radar, he believed that radar was to be the eyes of Britain's defence system. It is understandable then, that it was of great importance to Dowding that he had direct communications with radar stations from Bentley Priory. Over the last few years radar had improved by research and by trials. Dowding had faith in radar. 

It was at Orfordness in 1935 that radar had expanded to such a degree that further accommodation was required. Land was purchased at Bawdsey Manor near Felixstowe on the Suffolk coast, and here although the research team was quite small, the quality, variety and inventiveness was remarkable. By April 1937, they were engaged in radar trials endeavouring to locate aircraft flying on pre-arranged courses over the North Sea. The results were said to be confused and disappointing and Dowding thought that the general standard of information was as yet unacceptable for his Operations Rooms. Nevertheless, by August the same year a plan for the construction of coastal radar stations had already been agreed.

*Radar stations were already in operation at Orfordness, Bawdsey and Canewdon, and two others at Great Bromley and Dunkirk had yet to be completed. But by August 1937 it was decided to go ahead with the whole chain, making twenty in all. The probable average cost of each of the new stations would be:

Purchase of land  3,000 
Construction of towers  28,000 
Power, electrical distribution, stand-by-plant etc. 8,000 
Operational buildings 3,000 
Roads, paths and fencing 5,000 
Quarters for two warders 1,200 
Contingencies 3,800 
Total = 52,000 

The fifteen additional stations would cost 780,000 
For more powerful apparatus for each of the 20 stations @ 16,000 it would cost 320,000 in all. 
The total cost of the chain would be 1,305,000 
The annual operating cost was estimated at 174,000 
The Treasury gave sanction to the proposal on 13th August 1937
Dowding and Headquarters Fighter Command/Peter Flint p209 Appendix 3

Chain Home Radar Masts
Each of these would have four receiver masts that would be 250 feet high and four transmitter masts with each one being 350 feet high. The reason for duplication was their vulnerability to air attack, and the likelihood that transmissions would be interfered with or 'jammed' by the Germans. In the event of a mast or its aerials being damaged, or operating frequency being impaired, there were others that were ready to take over. To improve results they would be sited close enough together to form a chain where each station oversaw part of its neighbours detection area. 
In the photograph on the right, the transmitting masts can be seen on the left while the four on the right are the receiving masts that were constructed of wood to eliminate any stray reflections which may affect direction finding and height reading. 

Radar was in the hands of both civilian scientists and RAF Signals specialists, and after studying the results of the unsatisfactory trials in April 1937, Squadron Leader Raymond Hart was to become very influential in the study of radar operations. With other members of the team they agreed that if the radar stations were sited close enough together, then there would be an overlap in their fields of observation, which this would make it possible for every part of the coast to be watched. Although the technique made things complicated, it did require very careful handling and correlation of readings from two adjacent stations, but this method allowed the stations to be linked like a chain along the coastline. The system was approved by Dowding who, from early in the peace had great faith in radar and progress was being made with correlated information from the radar stations being relayed directly to the Bentley Priory Filter Rooms.

Air Chief Marshal Hugh Dowding was to stay at Bentley Priory for the duration of the Battle of Britain and until he was relieved of his position as AOC Fighter Command. The 'Priory' was constantly in use throughout the rest of the war and today stands as a monument to the operations that were conducted there that finally led to victory in WWII.

The Battle of Britain - 1940 website Battle of Britain Historical Society 2007