Defending the Heart - a visit to RAF Uxbridge

Gate Guardian at RAF Uxbridge is this replica Hurricane in 303 Polish Squadron colours (author's photo)

Early in November, I was lucky enough to pay a visit to the RAF 11 Group Ops Room, more popularly known as the Battle of Britain Bunker at RAF Uxbridge in Middlesex, which was responsible for the air defence of London and the Southeast of England and as such carried the motto 'Tutela Cordis' which translates to 'Defence of the Heart.'

No. 11 Group was part of RAF Fighter Command and was an integral part of what became known as the 'Dowding System', named after Fighter Command's first Air Officer Commanding-in-Chief and the man who, with a committee led by Henry Tizard, developed what was the first interlocking command, control and communication network. This comprised of a system of Fighter Groups, Squadrons and Sector Stations, linked to the radar, observer posts, anti-aircraft guns, balloon control all controlled from Fighter Command HQ at Bentley Priory, near Stanmore in Middlesex.

It was a work of genius, which was a cornerstone of British victory during the Battle of Britain and of which the Luftwaffe were never fully aware and who never understood its significance.

The Memorial at RAF Uxbridge (author's photo)

The Groups were the second link in the communication chain and filtered down all of the information received through to the individual sector stations within their respective groups, whilst passing the information up to Command HQ at Stanmore. Today, the 11 Group Ops Room is open to the public, currently by appointment only and has been recreated to appear exactly as it did during the Battle of Britain, more specifically for around 11:30 on Sunday 15 September 1940, the day we now commemorate as Battle of Britain Day.

Appointments are necessary because the nature of the bunker makes space restricted and therefore limits the size of the groups that can be accommodated. My appointment made, I arrived a little before 14:00 having made the short walk from Uxbridge Underground Station through the former RAF Station, much of which is currently being developed into a new housing estate. On formation in 1936, the 11 Group Ops Room was located within Hillingdon House but this was a temporary measure as it was realised from the outset that any such nerve centre would need to remain impervious to enemy air attack.

The bunker was constructed by the well known construction company Sir Robert McAlpine under conditions of strict secrecy between February and August 1939 and was thus available in the nick of time for war. The bunker is sixty feet beneath the ground and was designed to be immune to the heaviest bombs of the period. It was also designed with attack by poison gas in mind and contains a gas filtration system (which is still functioning to this day) which ensures that breathable air is available at all times to those working within the complex.

On the afternoon of my visit, we had a small group of three people booked, one of whom was a 'no show' and thus, our small party of two, led by Bob, our enthusiastic and knowlegeable guide, began the descent of the first flight of 87 steps down to the Ops Room.

The first of 87 steps down - and back up! (author's photo)

As we were a small group on the day, Bob was first able to show us the gas filtration room, which after 78 years still functions perfectly well. Our next port of call was the checkpoint, which today is recreated by an RAF Regiment Guard in mannequin form, together with a rack of 0.303 rifles and a secure grill to prevent unauthorised entry. Understandably, given the secret nature of this site in 1940, entry was strictly governed by pass only. Bob explained that it was here that the Ops Room suffered its only fatal casualty of the Second World War when a WRAF was killed by a rifle which fired as it was being cleaned by one of the duty guards, killing her instantly.

The Check Point entrance to the Ops Room (author's photo)

With this sobering thought in mind, we descended further down two more flights of stairs until at last, we reached the bottom level. Bob explained that the bunker has always had a problem with flooding, although during the years that it was operational, the space was manned around the clock and could be adequately controlled. This is not always the case today and Bob showed us the mark left by a summer thunderstorm in July 2015 which left the complex shoulder deep in water.

Bob shows us the 2015 flood level marked on the door frame (author's photo)

Having reached the Ops Room proper, although I had never visited before, it was a strangely familiar sight. This was because I had seen it (so I thought) in many films, perhaps most notably in the 1969 classic Battle of Britain and I asked Bob about this filming. It transpired that the film hadn't been shot in the Bunker, because at this time RAF Uxbridge was still an operational station and in any case, the Ops Room in its 1940 form was non-existent at that time. A team from the production company visited, took meticulous measurements and aided by photographs of the complex taken during the war, faithfully recreated the complex at Pinewood Studios - and so myths are demolished!

The 'Tote Board' and Plot Table (author's photo)

The Gallery - VIPs were accomodated on the far left (author's photo)

The main Ops Room is dominated on one side by the vast 'Tote Board' which fills one wall and by the elevated desks and the curved glass of the gallery on the other. The desks were occupied by the 'Tellers' who were in constant contact with the Sector Stations, Radar Stations etc. and the Gallery was home to the Duty Controller and the AOC, who during the Battle of Britain was Air Vice Marshal Keith Park. The glass protection was a must, as the main Ops Room, with it's legion of Tellers, WRAF 'croupiers' on the Plot and the constant ringing of telephones, was a noisy place and the Controllers up above needed a modicum of quiet in order to take the momentous decisions needed to control the battle.

Bob immediately set about explaining the Tote Board and its complexities. It was designed to display all of the relevant information at a glance. The place names displayed prominently across the top and bottom of the board - TANGMERE, NORTH WEALD, HORNCHURCH, KENLEY, BIGGIN HILL, DEBDEN and NORTHOLT - are the Sector Stations for 11 Group. The numbers displayed beneath each Sector Station are the squadrons assigned to each sector, for example for Northolt we see 1 (Canadian), 303 (Polish), 229, 504 and 264 B Flight, which was a night-fighter squadron at this period of the Battle and is thus shown as 'Released' on the Tote Board, as it is set for 11:30 on 15 September 1940. The descriptions beneath each squadron, such as 'Available in 30 minutes' etc., show the readiness state of each of those squadrons. The meaning of the coloured lights relates to the colours shown on the clock face, so for example with the clock at 11:30, the minute hand has just passed the 'blue' section on the clock face, so if the light is illuminated in blue, the controllers know at a glance that this is up to date information, if in yellow then ten minute old information, red fifteen minutes and so on, with the lights being lit in sequence. At the bottom of the status list, we then see the words 'State of Squadrons' - this is simple with 'P' equating to pilots and 'A' for aircraft, so again we can see at a glance that 1 (Canadian) Squadron at this precise point had 23 pilots but only 13 aircraft, 303 (Polish) 21 pilots and 17 aircraft and so on across the squadrons.

Weather and Balloon Status was also shown (author's photo)

Nothing was left to chance and the lower part of the Tote Board displayed the weather and visibility across all Fighter Command airfields and so apart from the Sector Stations, we now saw other familiar names from the Battle of Britain such as Hendon, Croydon and Martlesham Heath on display. For example, the cloud status was 8/10 cloud cover at 18,000 feet above Biggin Hill and visibility of three miles. The green disks told at a glance that the airfield was open - a red would indicated a temporary closure and a red/green would indicate usable with care. The status of the balloon barrage was shown, with the heights of the barrages at Dover, Gravesend, Tilbury and London all shown.

The Plot Table set for 11:30 on Sunday 15 September 1940 (author's photo)

Moving to the Plot Table, the same principal of showing at a glance the age and therefore the validity of the information to hand applied. Looking at the photograph immediately above, three raids can be seen heading across the Channel; these are marked 'H' for Hostile and the number '04' for example, signifies that it is the fourth hostile raid detected so far that day. The figure in red below indicates the number of aircraft in the raid, either based on the radar operator's judgement, or as observed by a member of the Royal Observer Corps. The arrows behind the raids are coloured according to the clock face, so in this instance a blue arrow represents the most up-to-date and therefore accurate information available and by looking at the progression of arrows, it is possible to plot the course of the raids as they head towards the English coast. The RAF fighter squadrons being deployed in response to the raid are shown in similar fashion, with the squadron numbers displayed on yellow flags atop the  wooden blocks, so we see that the first squadrons likely to intercept are 92 and 72 Squadrons, which comprise of twenty aircraft and which are patrolling at a height of 25,000 feet, in other words, with the advantage of height. Other squadrons are shown at various points, either patrolling over airfields, or ready to intercept before the raiders reached London. In the distance, just over the demarcation line between 11 and 12 Groups is a formation marked 'W' which shows fifty five aircraft patrolling at 20,000 feet. This is the Duxford Wing, or the "Big Wing" of 12 Group, which although it had let down Park in 11 Group earlier in the battle by appearing too late to be effective, on this day it was to have a devastating psychological effect on the Luftwaffe by appearing in large numbers, just at a time when the German pilots had been led to believe that the RAF was on its last legs.

From the Plot Room, we moved upstairs to the gallery area behind the curved glass. Part of this is still laid out with the desk for the Duty Controller, which during the Battle of Britain was Air Commodore Baron Willoughby de Broke, who during the Battle of Britain always ensured that he was available and never missed a single day's action. An interesting fact relayed by Bob our guide, was that contrary to popular belief, no RAF personnel slept in the bunker at any point during the war, the only person being allowed to do so was the duty GPO telephone engineer, so vital was it to maintain communications with the outside world and the 11 Group airfields in particular. Another interesting point of interest is that the map on display is the original dating from 1940, which when the Ops Room was restored to it's original Battle of Britain configuration in the mid-1980s, was found rolled up in a storeroom, gathering dust!

The view down from the Gallery (author's photo)

The remainder of the Gallery, along with many of the adjoining former offices, has been converted into a most attractive and interesting museum, housing models, uniforms, medals and memorabilia from the RAF's Second World War history and beyond. This was largely the work of Warrant Officer 'Chris' Wren MBE, who whilst stationed at RAF Uxbridge for the final nine years of his RAF career, took it upon himself to restore the Ops Room to it's former glory and made it a personal mission to achieve this end. Chris is now retired from the RAF and from overseeing the Ops Room but he can be extremely proud of the end result.

During the Battle of Britain, Winston Churchill was a frequent visitor and would sit in the VIP area of the Gallery watching the day's events unfold and indeed, it was following a visit on 16 August 1940 that he was so moved by what he seen, that he began to pen the speech that would include the now immortal phrase "Never in the field of human conflict, was so much owed, by so many to so few."
Churchill was again present on 15 September 1940, the day we see frozen in time at the Ops Room today but the Bunker was visited by many other VIPs during the war, including Field Marshal Montgomery and General Dwight D Eisenhower.

Air Raid Siren formerly mounted on the roof of Hillingdon House (author's photo)

Babys' Gas Mask (author's photo)

Other parts of the Museum are dedicated to the Royal Observer Corps, Bomber Command and to RAF Uxbridge. A slick looking new Visitor Centre is currently under construction outside in the grounds which is due to open in February 2018 and it is to be hoped that this new facility doesn't detract from the charm of the current arrangements too much. There is also a Lecture Theatre, and whilst we were undertaking our visit, watched a fascinating film made especially for the RAF in 1990 which highlighted the work of 11 Group. Bob mentioned that for school groups, who are also catered for here, he frequently shows the classic documentary "London Can Take It!" which dates from 1940.

Of course, the 11 Group Ops Room was at the centre of events other than the Battle of Britain, although this was undoubtedly it's 'Finest Hour' to coin a phrase. The subsequent fighter sweeps, known as 'Rhubarbs', a costly strategy envisioned by Keith Park's successor Trafford Leigh-Mallory, who had intrigued for the 11 Group AOC's post, were all controlled from here, as were the air operations for another ill-advised mission, the Dieppe Raid in 1942. The culminating moment came in 1944, when the air operations for Operation Overlord, the D-Day Landings were all controlled from the 11 Group Bunker and today a replica Spitfire Mk IX in "Invasion Stripes" acts as the joint gate guardian with the Hurricane to represent the two pinnacles in the Ops Room's history.

Replica Spitfire Mk IX gate guardian (author's photo)

The Battle of Britain Bunker in it's present format is open by appointment only until Friday 22 December 2017, after which point it will close until the new Visitor Centre opens in February next year. I highly recommend paying a visit and details as to how to book can be made by checking out the Museum Website as per this link. If you can, visit before the closure so that you can see the current arrangements before it is too late!