An example of the queries that comes to the web site about once a month
...and some of the replies our members send back.

Many thanks to all concerned.

"I am writing the history of the British Air Traffic Control Service"

~~~~~~~~~Any additional information is welcome~~~~~~~~~

27/01/2009 18:34

Hello there.

I am writing the history of the British air traffic control service.

I am currently researching the war years and it has become clearly apparent
that the ROC played a major part in helping crews who were either lost or in
trouble to find a place to land.

I would like to include the important part that the ROC played.

Do you have any advice or contacts for me who could add to the story?

Thank you.


From: Roy…
Sent: 09 February 2009 13:39
To: John...
Subject: Re: ROC

Dear John,
Sorry it has taken so long to fololw up on my acknowledgement of your enquiry.
I will forward this email to my usual contacts and also to three retired
air traffic control people who are known to our members.

09/02/2009 17:17


If you have three ex-Flying control officers on your books, I would kill to
have a word with them as they are the only ones I have found to date.

The R.O.C. played a major part in saving aircrew lives during WW2 and I want
to acknowledge this ignored part of our effort.

Thank you so much.


13/02/2009 08:16

Dear John,

I expect others have pointed you in the direction of Derek Wood's Attack Warning Red history of the ROC.

Another good reference source is F T K Bullmore's The Dark Haven which charts the development of flying control from 1939 and the part that ATC and the ROC played in saving many lost aircraft and their crews.

 Best wishes


03/03/2009 13:12

It was good to see you last night. I'll keep my eyes open for you when cycling Jubilee River next time.

Just to let you know my response to John...'s enquiry re the assistance given to aircraft lost and in danger by the ROC in WWII.

I suggested three sources of information. A brief reference in the DVD "Sentinels of Britain" and I scanned a page entitled "Flying Control and the ROC" from the book "Observers' Tale."(see below)

The bulk of the info was from "Attack Warning Red" so I scanned pages 66 and 67 and then pages 148 to 153 inclusive. John acknowledged all this but I don't know if there will be any further contact with him. He's currently in hospital for eight weeks.

He would love to talk to anyone left who was a Flying Control Officer or WAAF in a control tower in WWII. I wonder if any ROCA member might know of such a survivor?


12/02/2009 15:24

Dear John,
I note that you are writing the history of British Air Traffic Control Service. Interestingly my neighbour’s first and second husbands were both Air Traffic Controllers at Heathrow. Both now are deceased.

The Royal Observer Corps did indeed play a large part in helping crews lost or who were in danger of flying into high ground in WWII and beyond. I send you as an attachment an article called “Operation Granite” which explains how the ROC was used to stop RAF aircraft from flying into high ground.

ROC posts were also issued with HF radio, called Darky, for use in helping aircraft lost or in distress. Some ROC Posts were issued with searchlights for directing lost aircraft to the nearest airfield. Rocket flares called Totter were also issued to some posts mainly in the south east of England for directing fighters on to the tracks of enemy aircraft or V1s.

The ROC bible ‘Attack Warning Red’ by Derek Wood is a good source on al ROC matters. Another good book dealing with helping damaged or lost aircraft is ‘The Dark Haven’ by F T K Bullmore.

If you need any more details come back to me.

Yours sincerely

Attachment to the above email from Lawrence…



This is the story of the measures taken by the Royal Air Force and the Royal Observer Corps to prevent aircraft flying into high ground. The article appeared originally in the magazine AERONAUTICS.

The Granite scheme, or as we call it “Operation Granite” is not so well known amongst those whose posts were situated in the non-hilly regions of our Island, and this account of it will serve to illustrate one other aspect of the ROC’s varied war-time tasks. To those who have worked the scheme and know all about it, there will be the satisfaction of seeing just how valuable their long weary watches really were in the matter of saving lives of members of aircrews, and in saving aircraft.

The story shows that the experience gained in its use may well mean the revival of this operation or something very much like it, if the Royal Observer Corps is again called to “action stations”. Operation Granite will eventually be brought within the scope of the training plans of the ROC.

During 1946 many civil and service aircraft were lost through flying into high ground, and the public naturally asked what was being done about it. The only official answer was to the effect that experiments with radar as a means of warning aircraft that obstructions were ahead were under way, but they had not been perfected.

During the late war large numbers of aircraft were lost each year in the British Isles through flying into high ground, but the Royal Air Force were eventually in a position, with the help of the Royal Observer Corps, to combat this menace with a scheme known as “Granite”. The idea was to light powerful red ground flares in the path of an aircraft observed to be flying towards high ground, so that the necessary avoiding action could be taken by the pilot.

In above two diagrams high ground of 300 metres (1000ft) or more is indicated by the shaded areas. In the shaded area left, it will be seen that there were 10 high ground accidents. After Operation Granite had been working for a period, no high ground accidents occurred between 1 January and 31 December 1944 right. The two charts give a good example of the deployment of the Royal Observer Corps posts.

The Royal Observer Corps, through the medium of their observer posts, were ideally situated to see when an aircraft was running into trouble, and those posts in the vicinity of hills and high ground were issued with a quantity of red flares (Flare, ground warning, Mark 1), which would burn for about three minutes. One flare was lit at night, but in order to get the same degree of brilliancy by day, it was found necessary to light four. They were arranged in the form of a rectangle 9 by 1 meters (30 by 3 feet). They were replenished with new flares as long as they were required.


These two illustrations cover the North Wales area. Before Operation Granite high ground accidents were common in this area (left). Afterwards they were markedly reduced (right).

At the start of Operation Granite, which was in full swing at the beginning of 1944, the regions of high ground in the following areas were included in the scheme :-

North and north-west Wales.
The east boundary of the Welsh hills.
The east and west sides of the Pennines.
The Lake District.
South-west Scotland.
The Isle of Arran.
The hills north and west of Montrose.
The Ochill hills.

The following number of ROC posts were equipped with flares in their respective areas :- Derby area 16, Manchester 6, Leeds 20, York 17, Wrexham 19, Shrewsbury 18, Caernarvon 13, Lancaster 15, Durham 11, Carlisle 21, Ayr 20, Glasgow 4, Dunfermline 13, and Dundee area 13.

The Granite scheme was gradually extended to cover all the hilly districts in England, Scotland and Wales. This brought in the Exeter area, which had 16 ROC posts equipped with flares. There were no Granite posts in Cornwall. By the 26th of April 1945, 340 ROC posts were ready to take part in Granite.

The procedure necessary to bring Granite into operation was as follows :-
When by day the observer at an ROC post from which the 300 metre (1,000 feet) contour of nearby hills was visible, saw low cloud down to this contour, he informed the ROC centre, who in turn instructed all posts in the area concerned to report all aircraft movements, and all posts equipped with flares to have them ready for immediate use.

By night it was the responsibility of the Flying Control liaison officer at the appropriate Fighter Group to instruct the ROC liaison officer to order Granite to be put into operation through the appropriate ROC centre.

Granite was also put into operation when an aircraft was known to be moving towards high ground at such a height and on such a course that the pilot did not obviously intend to land at any airfield in the area, and might be in danger of flying into high ground. A red flare or flares would be lit at each post within 16 kilometres (10 miles) in front of the aircraft, and 16 kilometres either side of the track.

As can be seen from the diagrams above, the posts were located close together so that a pilot would be warned by many flares while approaching high ground. Observers were allowed to light flares on their own initiative if it was a matter of saving time. During flight briefing prior to take-off, pilots were warned to turn on to a reciprocal course as soon as they saw the flares. It was not sufficient to turn to port or starboard as dangerous high ground might still lie ahead of the aircraft.

Scores of instances were recorded of aircraft taking action when the flares were lit. On the 7th of April, 1945, at 09.43 hours, a Fortress north-west from Hucknall flying at 600 metres (2,000 feet) increased height to 1,500 metres (5,000 feet) and continued on course. On the same day at 13.59 hours another Fortress flying at 150 metres (500 feet) changed course to southeast, and at 14.05 hours a Fortress at 240 metres (800 feet) climbed to 300 metres (1,000 feet) and continued on course.

Between 09.14 and 10.05 hours on the 12th April, 1945, of six aircraft, five increased height and one turned on its reciprocal course and on the 26th of the same month, of twelve aircraft, five changed course and seven gained height and proceeded on their course.

A large number of positive results were noted from the flight reports of pilots. One worthy of notice occurred in the Pennines area in March, 1945, when a Hudson with a V.I.P. on board climbed steeply from 300 to 1,200 metres (1,000 to 4,000 feet), a safe height in this area. Another case occurred the following month when a Wellington from Dalcross flying south-east towards the Grampians at 600 metres (2,000 feet) subsequently increased height to 2,000 metres (7,000 feet) and returned to Dalcross. On this occasion four flares were lit. Satisfactory results were recorded when observers at ROC posts lit flares on their own initiative.

At 13.48 hours on the 10th of October, 1944, an observer seeing a Domini flying at 90 metres (300 feet) towards high ground immediately lit a flare. The aircraft was seen to turn on to its reciprocal course and was traced through other observer posts to its base. The pilot afterwards reported that he had seen red flares and realised he was flying into high ground due to bad weather and changed course. On another occasion earlier in the same year an observer lit a flare when he spotted an Anson at 90 metres (300 feet) flying towards high ground. The aircraft immediately turned eastwards and increased height to 600 metres (2,000 feet).


The area containing the Pennine Chain south-west of Newcastle and the high ground south of Carlisle are shown here. Most of the accidents in this area between the 1st of January 1943 and 1 December 1943 occurred in the hills south of Carlisle, in Cumberland, where Skiddaw, 1,030 metres (3,054ft) and Scarfell 1062 metres (3162 ft) are situated. There are 13 high ground accidents shown in the left diagram and three in the right. By March 1945, 91 observer posts equipped with flares were established covering the Pennine Range area. The high ground accidents shown befell RAF aircraft only. Casualties to United States Army Air Force aircraft are not included in any of the diagrams illustrating this article.

Up to the end of March, 1945, flares had been lit on 521 occasions and 261 aircraft had been observed to take various forms of action. Details are shown in the table at the end of this article. The aircraft not accounted for in the figures shown probably did not come into the visual range of the observer posts, and their actions could not therefore be recorded.

In the diagrams shown on pages above the contours enclose high ground of 300 metres (1,000 feet) or more. These illustrations are typical of the Granite scheme for the rest of the country, and they show a marked drop in high ground accidents. The periods covered are from the 1st of January 1943, to the 1st of December, 1943, and the 1st of June, 1944, to the 31st of December, 1944. (The figures from the 1st of January 1944 to the 31st of May 1944, are not available). Eleven months against six may not be considered a fair comparison, but the number of aircraft airborne during the shorter period is said to have been twice that for the same period in the previous year.

The Royal Air Force were not content that Granite should be the only means of warning aircraft of danger ahead, and from time to time they introduced other methods to augment the scheme. The most important of these other aids was the installation on high ground of a wireless transmitter which emitted a note lasting half a second, every six seconds, on the common 6,440 kilocycle Darky frequency. A pilot on hearing this signal would be warned, and would exercise extreme caution and take the necessary action.

In the Scottish area mountain warning beacons were established at Auldgirth, Porton and Bargrennan. In the north-west and Caernarvon areas, beacons were installed at Snowdon, Overton, Llanymech, Llanfairfechan and Portmadoc, and others were placed at Broughton, Kendal, Staveley, Ripley (Derby), Dalston, Allonby, Scawfell, Skiddaw, and in the Isle of Man.

The maintenance and servicing of these transmitters was done by the appropriate group in whose area they were installed. Those in the Scottish area, for instance, were maintained by 33 Group. Some ROC posts were also fitted with R/T transmitting sets, so that observers could pass warnings to aircraft where possible.

Flying Control liaison officers at fighter groups would also try to contact aircraft in danger by passing warnings on the Darky frequency, by instructing rockets to be fired from airfields, or by ordering the searchlight homing procedure for lost aircraft to be put into operation.

The Granite scheme was dependent for its success on the co-operation of the large personnel of the ROC and when this organisation was disbanded at 17.00 hours on the 12th of May, 1945, Granite died.

If such a scheme could be revived in England and adopted by other countries, it would go a long way towards eliminating high ground accidents. The Granite scheme required a large number of people to operate it, and even if it could be reestablished in a modified form with, say, 250 observation posts instead of the 340 that were partaking in the scheme in April, 1945, it would require four people at each post to ensure a twenty-four hour watch. This would mean 1,000 people employed, and if they received £5 a week each it would mean an outlay of £5,000 a week in salaries alone. This may be considered too high a price to pay for the results that would be obtained. An alternative method might be devised which would incorporate the use of powerful red neon lights in place of flares.

They could be illuminated in groups and operated from key observation posts. In the illustration on page 1, for example, the 28 posts could be divided into four convenient groups. The substitution of neon lights for red flares might also prove more economical. It is not known whether the Ministry of Civil Aviation has given the matter any consideration, but it may be worth their while to investigate the possibility of reviving the Granite scheme until a better one is found.


This table gives an analysis of the action taken by pilots as a result of the lighting of 521 red flares at Royal Observer Corps posts up to the 31 March 1945. It is a progressive table, and it will be seen that the greatest number of flares were lit in the dangerous winter months.

no Action
 and Climbed
To 30th April 1944 92 24 31 22 15
To 31st May 1944 100 27 34 24 15
To 30th June 1944 116 31 37 30 18
To 31st July 1944 132 35 44 32 21
To 31st August 1944 143 38 47 37 21
To 30th September 1944 170 46 54 43 27
To 31st October 1944 235 54 63 59 30
To 30th November 1944 250 56 64 65 32
To 31st December 1944 289 64 65 75 36
To 31st January 1945 336 71 69 92 42
To 28th February 1945 450 149 90 104 45
To 31st March, 1945 521 176 99 115 47


1. An Observer's Tale - the story of 17 Group ROC - Page 37 - Printed by Roland Bros 1947 by Chief Observer C H Gibbs-Smith(?).

2. The Observer Corps was formed...

3. A Granite post at Brassington

4. Note: Many years ago John... and Colin… worked together at West Drayton ATC.

5. Not all replies are were copied to me. Roy

[03jun09 00:40]