Christer Bergstrom BOB book

[Nick Beale]

Originally Posted by John Beaman

John, you are right. IIRC, Bletchley Park were just getting started, in any useful sense, with ULTRA, so any info on "the other side of the hill" was VERY sketchy.

They had a major break into Enigma just before Dunkirk (and then some retrospective breaks into older material) and were getting quite a volume of Luftwaffe material throughout the BoB. BP seems to have been constrained by staff shortages and lack of Bombe machines, so they were only breaking into a few networks. They did however manage to put together a pretty good order of battle and locate a large number of the units on it, with detailed strengths for some. With a typical 24-hour delay in deciphering, there weren't too many dramatic warnings but a lot of individual items that accumulated into a bigger picture. And the ULTRA material shouldn't be taken in isolation — take the case of Knickebein and X-Gerät where it was the combination if decrypts, prisoner intelligence, wreck investigation and signals intelligence that enabled the RAF quickly to understand how the beams worked, on what frequencies and where they were being directed each day.

Another frequent subject of the messages, incidentally, is damage inflicted (or not) by RAF bombers on airfields in France.