“One Night in November” – Bletchley Park, Churchill, Coventry
Released : Apr 4, 2008
The Truth behind the Myth
“One Night in November” is currently showing at the Belgrade in Coventry. Playwright, Alan Pollock’s play is a fictional love story based on the premise that Churchill had the moral dilemma of having gleaned intelligence from Bletchley Park that Coventry was to be bombed but decided to do nothing and sacrifice the city. "I'm quite prepared for the ire of the Churchill apologists," says Pollock. "But my strong feeling is that when he knew the target was Coventry, he made a spur-of-the-minute decision that Coventry was expendable”. (The Guardian, Tuesday 4 March)
Historical fact is beginning to merge with fiction in the current media debates over this play.
To clarify historical accuracy and to distinguish fact from fiction, Bletchley Park Trust would like to convey the truth behind the myth. There are numerous examples of Churchill not hesitating to suppress valuable intelligence derived from Bletchley Park decrypts, when there was no other plausible source for that Intelligence, in order to preserve the vital secret that BLETCHLEY PARK was breaking the major German codes such as Enigma. The raid on Coventry on 14th November 1940 (Operation Moonlight Sonata) was NOT one of them.
Bletchley Park frequently played its part by providing warning of forthcoming raids, but unfortunately on the occasion of 14th November, though warning that a major raid was coming on about the 14th, BLETCHLEY PARK was unable to provide evidence that the target was Coventry as the codeword ‘Korn’ had not appeared in decrypts before and so was not recognised as referring to Coventry. It was the RAF who identified the target as Coventry at about 3 pm that afternoon from the German navigation beams, once they were set-up. The defences were immediately warned. Churchill was travelling that afternoon, and returned to London at about 4 pm under the impression that the target was London. He may not have learnt, even then, that the target was Coventry until that evening. He had ordered the strengthening of the defences of the Midlands some two weeks before, and this had been carried out. There was nothing he could have done to further strengthen the defences that had not already been implemented, had he known the target was Coventry earlier that day.
Background. At the time in the autumn of 1940, BLETCHLEY PARK and Air Ministry Intelligence had several ways of determining the likely target for a forthcoming Luftwaffe raid:
1) BLETCHLEY PARK’s Hut 6 had broken the Brown Enigma key (a Luftwaffe key) on 2nd September 1940. It turned out to be the key used by the German technical team who were directing radio beams for bomber navigation. Despite the few signals that were sent, Brown was mainly very easy to break. This team sent a message at about mid-day, on every day when there was to be a raid that night, stating the target for the night. Then, about two hours before the beams were due to be switched on, detailed instructions would be sent on beam directions, etc, for the raid of that night. At that time most raids took place soon after nightfall and the beams were set up some hours before the pathfinder bombers (of K.G. 100 group – the first pathfinder bombers) were due to take off. Within the Enigma messages the target identity would be disguised by a code-word or number which changed infrequently. In the autumn of 1940 Bletchley Park’s Hut 6 was giving priority time to these Brown intercepts in order to try to get the identity of the target out to Fighter Command in time to enable them to deploy their, then, limited night-fighter resources optimally.
2) The position of the beams, of the X-Gerät navigation system, could be detected by special RAF flights, once the beams were set up during the afternoon. The RAF learnt to fly along the beams until the target was found where they intersected.
3) Occasionally Luftwaffe careless signals would give away the target.
The Improvement of the Air Defences of the Midlands, and of Coventry in particular, had been ordered by the Cabinet early in November, and as a result, Coventry’s defences had been strengthened somewhat by 14th November. A special RAF counter-plan, ‘Cold-Water’, against the coming major raid, was implemented from 12th November.
Intelligence about the Forthcoming Raid. On 11th November an Enigma decrypt gave early warning that the Luftwaffe was planning an unusually large and important raid. The name ‘Moonlight Sonata’ suggested it would be a night attack near full moon. It gave a list of four targets and the code-name ‘Korn’ appeared in it. On 12th November a P.O.W. (it seems likely the cell he shared with a ‘stool-pigeon’ was bugged) stated that a heavy raid was planned between 15th and 20th November with Coventry and Birmingham as targets. However, from a captured map, Air Ministry Intelligence (of which Air Section at BLETCHLEY PARK was formally a part) deduced that the four targets were located in London and the Home Counties.
On 12th November a second decrypt gave the beam bearings for three targets which plotting showed to be Wolverhampton, Birmingham and Coventry. But similar signals had been decrypted before relating to Luftwaffe experiments, so this was not associated with ‘Moonlight Sonata’. Air Ministry issued rather general operational instructions, without naming the target.
On the morning of 14th November, the RAF alerted the Prime Minister, and Commands, to the coming raid, saying, ‘We believe the target areas will be … probably in the vicinity of London, but if further information indicates Coventry, Birmingham or elsewhere, we hope to get instructions out in time’.
At about 1300 hrs on the 14th, it became clear from Luftwaffe Wireless Transmitter traffic and beam transmissions that operations were to begin that night. Churchill was on his way by car to Ditchley Park, near Oxford, but he returned to London when he got the message about the raid coming that night, under the impression the raid was to be on London.
At about 1500 hrs, the RAF established that the beams intersected over Coventry. This information at once went to RAF Commands and other authorities. However, Churchill apparently did not learn this until he arrived back into Downing Street at about 1600 hrs. Writing in 1976, two senior members of his staff say he remained under the impression the target was London ‘for the rest of the day’, presumably until he read the 1500 hrs report from the RAF in his box that evening.
The Raid on 14th November. The defences of Coventry proved woefully inadequate, as they were virtually everywhere in the UK at that stage of the war. Ten Pathfinders from K.G. 100 led the raid, illuminating the target with flares. Some 500 bombers followed; 440 reached the target, but only one was confirmed as shot down. RAF beam jammers of X-Gerät were being used for the first time, but unfortunately there was an error in their tuning which made them ineffective that night. A firestorm was started which destroyed much of the square mile round the city centre. Some 60,000 out of 75,000 buildings were destroyed or badly damaged; 568 men, women and children were killed. Twenty-seven vital war factories were hit.
Simon Greenish, Director of Bletchley Park Trust, comments, “Bletchley Park was the wartime codebreaking centre where some of the greatest minds of the twentieth century gathered, not to make strategic military decisions, but to provide the Intelligence for Churchill and other Allied Leaders to do so. Throughout history, the morality of wartime decisions made by military leaders has sparked debate. In this case, Coventry was not identified as the city to be bombed until it was too late, as is clearly demonstrated by the records, therefore no such decision was made. I do, however, wish Andrew Pollock every success with the play which explores the morality of the reality of war.”
Sources. 1) Harry Hinsley’s ‘History of British Intelligence in WWII’, Vol I p 316 – 322, and Appendix 9 p 529 – 548.
2) R.V. Jones in his ‘Most Secret War’ chapter 18, pm 146 – 153
3) H. Hinsley ‘Codebreakers’ p 253
4) Details about the actual impact on Coventry can be found in many historical accounts. The figures used here come from the Appendix 9 listed as 1) above, others quote other figures.
4) History of Hut 6, National Archives HW43/70.