Key Dates in the History of the Royal Observer Corps

Please note the following details were originally taken from the Norfolk and Suffolk Aviation Museum website, which I felt was a good starting point...

These records were supplemented by extracts and information from the following...
Attack Warning Red [Derek Wood],

Cold War Building for Nuclear Confrontation 1946-1989 [W.D.Cocroft & R.C.Thomas], 

Forewarned is Forearmed [T.E.Winslow], 

Forewarned is Forearmed [H.Buckton], 

Protection From The Cold [S.Craine & N.Ryan], 

ROC Underground Monitoring Posts [M.Dalton] 

Watchers over the Broad Acres [N.Spence]

John Rimmington November 2016

Key Date information is shown in Bold


Royal Observer Corps has its roots in the Elizabethan Beacon Lighters who faced their first major test when the Spanish Armada arrived off of the coast in July 1588, which was decisively sunk at sea. Beacons were used for defensive and warning purposes from the early 1300s to the mid-1600’s.


In World War One there was a need in the Greater London Area to warn the military, government, transport etc. of approaching enemy aircraft and airships. Initially policemen telephoned reports of any aircraft seen or heard within 60 miles of London to the Admiralty who were then in charge of defence


By this period, this area was increased to cover the South and East of England.


The War Office took over defence in 1916. Coastal Plotting Posts were established and manned by Special Constables whose reports went to the London Air Defence Area (L.A.D.A) operations room in Horse Guards, London. Here there were plotting maps and communications to AA guns, aerodromes and telephones to the posts. The Organisation became known as the Metropolitan Observation Service. With the end of the Great War the service was stood down.


During the First World War there were 103 bombing raids with 1,413 people killed (607 in London alone) and 3,407 injured.


After a number of Air Defence exercises using Police Observation Posts the Observer Corps was established with two groups of posts manned by Special Constables under Major General Ashmore (Army), the Home Office and the Royal Air Force.

1929 January 1st

The Observer Corps taken over by the Air Ministry. Observers remained Special Constables

1929 October 22nd

The Beacon Lighter Badge and Motto “Forewarned is Forearmed” was announced


Start of a six year expansion programme as tensions and aerial technology within Europe began to grow.

1938 September 26th

Observer Corps called out, and then released a number of times until 1st October because of the on-going “Munich Crisis”.

1939 August 24th

The Observer Corps is mobilised on a war footing. For the next five and a half years no post or centre was unmanned. Observers ceased to be Special Constables and transferred to the Air Ministry.

1940 April

From April coastal area posts were put on ‘special watch’ and asked to report: Gunfire, Explosions, Parachutes, Coastal Landings, Shipping and Convoys and Suspicious vehicles, people and lights.

1940 May

From May coastal and exposed posts issued with two rifles, bayonets and ammunition.

1940 July-October

The Battle of Britain; Friend or foe were plotted giving essential information to the RAF Groups and Sectors. During this period the Luftwaffe lost about 1,800 aircraft. At the same time as plotting and observing German aircraft formations, the posts would also plot loose Barrage Balloons, bombs, crashed aircraft and whether or not the crew had bailed out of the latter. Crews also helped with the capturing of German Aircrew, and came to the aid of British Pilots who had been shot down.

1940 September

Special OC posts in London took over air raid warnings for the House of Commons and 400 departments of the government and military; later factories were added to this list

1941 April 9th

Royal Observer Corps… In recognition of the Corps excellent work, King George VI granted the title Royal to be added to the Observer Corps official title.

1941 May 10th

ROC crew correctly plotted the Messerschmitt Bf-110 which had been commandeered by Rudolf Hess as he tried to escape to negotiate peace with Britain against Hitler’s will.

1941 July

Authority given for women to join the Royal Observer Corps with the same rights, status and on merit the same rank as male observers.

1941 September

Members of the Radio Security Service were allowed the wear ROC uniform as ‘cover’ for their secret radio listening watch.

1941 December

Agreed that RAF two-piece blue battle-dress to be issued to all male and female observers.

1942 August/September

Satellite posts established near the coast to give better coverage against Fock-Wulf Fw-190 hit and run raids. They also gave air raid warnings to coastal towns. Coastal ports were also issued with ‘Totter’ rocket projectiles to alert AA gun crews and any nearby fighters as well as local residents that a German attack was approaching the area.1942-October- 45 ROC posts (London locally) were equipped with TR9D high-frequency short-range radio sets, with a range of about ten miles. Under the code word “Darkie”, damaged or lost aircraft could call up on the TR9 and the post would give them the bearing and distance to fly to the nearest diversion airfield; in the case of London it was RAF Coltishall who would turn on a canopy of searchlights to guide the aircraft to them. Other posts were equipped with searchlights to point towards the diversion airfield closest

1942 November 15th

Ten posts equipped with gun laying (GL) radar sets (Locally: Brundall, Docking, Melton Constable, Halesworth and Orford Posts) to enable ROC to pick out enemy aircraft in returning bomber formations, aiding RAF night fighters.

1943 July

Coastal posts were to report any carrier pigeons heading out to sea that may have been released by enemy agents

1943 November

ROC posts requested to report any dangerous low flying RAF pilots and include unit markings and the time of the incident

1943 December 12th

The first Master Test was held. Observers had to score 180 out of 200 in aircraft recognition tests to pass

1944 April 22nd

ROC took over all Red, Purple and White air raid warning in the UK. The Corps were not allowed to sound the air raid warning for single aircraft because the government considered it better to suffer slight damage than disruption in factories, offices etc.

1944 May/June/July

ROC ‘Seaborne’ Observers, with the naval rank of Petty Officer, served on board some ships taking part in the D-Day invasion. These 796 men controlled the AA guns, their ages ranging from 17 to 70 years old. US and Royal Navy personnel relied on the observer’s knowledge of aircraft recognition. Two observers were Killed In Action

1944 June 13th

Under the codeword ‘Diver’ the first V-1 flying bomb was correctly identified and plotted. Thousands more V-1s were to follow the first. Some coastal ROC posts were equipped with “Snowflake” rockets to show the track of the V-1s within two miles of their posts to help patrolling fighters. Further inland, towards London, other ROC posts were equipped with Red Star rockets to warn fighters chasing V-1s that they were approaching the Balloon Barrage

1944 September 8th

The first V2 rocket impacted at Chiswick. About 1054 were to follow until 27th March 1945. The ROC were unable to give any warning to the public, but if post members saw the trail of the rocket as it took off from the continent, the post was required to give its bearing and angle; with other posts doing likewise the launch-site could be pinpointed and attacked where possible.

1945 20th March

Final Luftwaffe air raid.

1945 8th May

VE-Day. The ROC was stood down for four days later at 17:00 hours. Between 1943 and the end of the war, the ROC played their part in saving over 7,000 aircraft and crew using the ‘Darkie’ TR9D radio, along with 340 ROC posts equipped with ‘Granite’ flares; these warned pilots that they were approaching high ground and if they kept heading in that direction they would crash To help further 15 high ground posts were equipped with ‘Augmented Granite’ being a special radio on 6,440 KHZ which gave an audible warning to the pilot. It was known as the ‘Mountain Warning’ beacon.

1947 January 1st

The Royal Observer Corps was officially reformed, to become part of Britain’s Air Defences. Training started afresh as did visits to RAF stations.

1947 September

No’s 1 and 2 Groups, Maidstone and Horsham, were put on an operational footing with all their posts and centres operational within four hours. Jewish Terrorists of the Stern gang threatened to drop explosives from light aircraft onto London. The ROC proceeded to track all aircraft, in co-operation with No II Group Fighter Command and their standing patrols of fighters. The emergency came to an end within a day when the Terrorists were captured in Paris


Annual Summer Training Camps established. First Camp at RAF Thorney Island


Trials held with the ROC being equipped with AMES TYPE 6 MK 8 radar sets, and the American AN/TPS2 mobile radar sets. Both were rejected as the MkI eyeball was better! It was several years before the RAF had decent radar coverage, in fact during the 1948 air defence exercises, Chain Home Extra Low (CHEL) radar stations only detected 2 out of 19 low-level raids. All raids however were detected by the ROC.

1950 April 11th

To mark the Silver Jubilee of the ROC, HM King George VI became Air Commodore-In-Chief of the Corps. The ROC long service medal (12 Years) was issued, and the shoulder flash replaced the breast badge on the battle dress with the group number indicated below.

1952 – 1955

Between 1952 and 1955, the ‘Orlit’ prefabricated concrete aircraft reporting post replaced many earlier structures. At this time the RAF had more than 6,300 aircraft.

1953 June 1st

HM Queen Elizabeth II became Air Commodore-In-Chief of the ROC. Nine Group Headquarters closed down, (Locally Bury St. Edmunds) other groups taking over their posts with new borders


ROC posts were asked to plot “Unidentified Flying Objects” under the code name ‘Pheno’. There were at least three known incidents in the No.6 Group, Norwich Area.


The ROC was given a role by the Home Office, that of reporting radioactive fallout from nuclear weapons. To allow this, the ROC was also given new equipment to allow bomb burst positions, heights and powers to be calculated. The ROC was to become part of the United Kingdom Warning and Monitoring Organisation (UKWMO). The 1945 Atomic Bomb dropped on Hiroshima was 20 KT, (20,000 tons of TNT). An American Hydrogen Bomb tested in March 1954 had the power of 15M (15 million tons of TNT; The Russians were also testing such weapons, and just six years later, in 1961, the Tsar Bomba (Tsar Bomb) was tested in Russia, which had a yield of just over 50 Megatons of TNT, though it was estimated by leading scientists that the yield could be 100Mt if needed. It is still the largest nuclear weapon ever detonated. The largest US bomb ever was only capable of 25Mt. All explosives used in The Second World War, including Nagasaki and Hiroshima Nuclear detonations, is only estimated to have added to 3Mt, to give a sense of scale.


All ROC posts and many Group Controls/Headquarters were built underground, although the one at Windsor Castle was a much modified coal cellar
In total 31 Group Controls were constructed and ranged in design from semi-sunk (12); surface (13) or existing buildings (6). [PFTC p93]


United Kingdom Warning and Monitoring Organisation [UKWMO] established


Aircraft reporting became a secondary role; priority went to the reporting of nuclear bursts followed by reporting fallout.


Post issued with hand sirens and maroons to warn the public of air attacks and fallout, via the carrier recover and the Ballistic Missile Early Warning Station (BMEWS) at RAF Fylingdales.


Teletalk replaced the head and breast set telephone.

1966 June 24th

Silver Jubilee Royal Review of the Royal Observer Corps at Bentley Priory, when the Queen presented the Corps with its banner. [WOTBA p110]


Complete rebuilding of group controls and reorganisation of communications throughout the UKWMO to incorporate high speed teleprinter and telegraph links, provision of radio links to supplement line communications, posts given better rations and tommy cookers, improved lighting, batteries and a petrol generator.


The 1968 Re-organisation: The Civil Defence Corps and Auxiliary Fire Service were disbanded. Fight and Bomber command merged into Strike Command. 686 ROC posts closed along with two Group Controls


Links forged with the Royal Danish Ground Observer Corps. Data transmission introduced.


New style uniform issued to all observers replacing the mid-50’s Battle Dress


50th Anniversary of the formation of the corps.


Low-level aircraft reporting and plotting trials held in the Eastern Counties.


Installation of new communications network begins, computers replacing the teleprinters.

1981 September

All Posts lost their alphabetical designation and were known simply by a number. All Master Posts, the designated senior post in each cluster, had numbers finishing with either a nought or a five, whilst the Clusters where known by Master Post number. [WOTBA p173]


60th Anniversary Garden Party.


Royal Observer Corps Association [ROCA] established


Final Annual Summer Training Camps held at RAF Watton

1991 July 25th

Review of the Royal Observer Corps by HM Queen Elizabeth II accompanied by the Duke of Edinburgh at RAF Bentley Priory.


Stand down of the Royal Observer Corps, although a few hundred ROC members continued until 1995 operating as Nuclear Reporting Cells (NRC’s) for the armed forces until they too were stood down.