Firstly, SES, thanks for your feedback on the Air Ministry report. As mentioned previously, such reports are the best estimate of what Air Ministry Intelligence thought was going on and you have highlighted perfectly the pitfalls of using such material - it can be used as a starting point but all such information should be checked and validated against another independant source.
Anoher such example are the Operational Research Section estimates of cause of loss for missing Bomber Command aircraft on night raids (as contained in the ORS Interception Tactics Reports and Final Reports of Night Raids). Of course, these are based on reports by returning crews but even in March 1945, for example, 30-50% of losses at night are still attributed to flak. IMHO, this figure includes attacks by night fighters from below using dim tracer (and thus being described as light flak by returning crews).
However, some clarifying points:
The intrepretation by ADI of the captured Duisburg flak map was that it had the potential Oboe course lines marked on it, based on the positions of the Oboe ground stations. It was assumed that to correctly predict the course of an Oboe-equipped aircraft, the broadcasting stations being used would have to be known in order to know which course lines were being used. It was further assumed that this technique could be more accurate than straight plotting by interrogation. I am not saying this is neccessarily a correct assumption but only what the report is saying.
With regards to the late war H2S usage, the operational orders and Interception Tactics reports that I have for Jan-Mar 45 make it clear that signals silence was imposed up to the frontier so that H2S etc was only used in enemy territory. In March 1945, for example, the PFF was generally NOT laying ground markers for turning points (and I have confirmed this with ex-aircrews) and the radar signals ban equally applied to them. Of course, individual crews did break the rules and thus gave the Luftwaffe the opportunity to detect signals. In the main, many bomber streams, based on W/T sigint, were not clearly plotted early, or at least not until after they had passed through the mandrel screen and when the usual tactics of ,firstly, sending in a shallow penetrating force, followed by a deeper penetration force, both via France and/or Belguim, the latter force was usually not heard to be plotted until well over the frontier. The trend that followed is that if the initial penetration was shallow (i.e. to the Ruhr), losses where generally light as the night fighters could not get into position to intercept in time but when the penetration was deep, or took a deeper route, the first bomber stream often suffered heavy losses while the later stream had a comparitively easier time of it.
IMHO, some of the successful inflitrations of night fighters into the bomber stream in March 1945, owed just as much to fortuitous initial positioning of n/fs around beacons and/or correct analysis of intentions (based on repeated operational patterns of Bomber Command) as to early and clear detection of the bomber stream route.
If you are prepared to wait for the publication of Dr. Theo Boiten's 'Nachtjagd War Diaries', late next year, you will find some quite detailed descriptions of the course of some of these nightly air battles, including details of the moves by the fighter controllers.
For Jan,
With regards to ordering microfilm duplicates of ULTRA from DEFE 3 at the British National Archives, firstly, you will need to find the files that you are after in the online catalogue. You can either search or browse the DEFE 3 entries (of which there are many!). To search, for example:
http://www.catalogue.nationalarchives.gov.uk/search.asp
Word or Phrase: German
Year Range: the year range you are interested in
Department or Series code: DEFE 3
Such a search should bring up all the entries for that year so you need to find the correct dates. Beware, any reference you find must be under the "MAIN SERIES OF SIGNALS CONVEYING INTELLIGENCE TO ALLIED COMMANDS. BASED ON INTERCEPTED RADIO MESSAGES." - you can verify this if you open an individual entry and look under the 'Full Details' Tab.
Copies of documents, in paper, microfilm and digital format can be ordered via:
http://www.nationalarchives.gov.uk/r...e=ddmenu_shop3
You will have to register first to make a request for an estimate. The ordering system is easy to navigate and:
1. a request for an estimate for paper copies costs GBP10 (deducted from total payable if you go ahead and order). Copies from up to five different files can be requested.
2. a request for an estimate for microfilm costs GBP20 (deducted from total payable if you go ahead and order). With ULTRA, the microfilm original already exists and thus costs GBP1.80 per metre to duplicate (where no microfilm exists then it costs an arm and a leg to get a file microfilmed (GBP58 per hour) so whoever gets it done first pays and 'arm and a leg' while anyone requesting a copy once the microfilm is made will only pay GBP1.80 per metre!). Because the DEFE 3 ULTRA material is in roughly 3-day lots, it would pay to get material for
at least a week after an event you are looking for and even that is no guarantee that the material is there.
Once you make an estimate and payment is processed (by either credit card or cheque) it will take up to two weeks for the estimate to be completed. You will be e-mailed once it is done so that you can login to their ordering system to view the estimate. Then you can make the order and payment. Once you place an order and they have processed the payment, the target turn around time for duplicating the microfilm is 19 days.
'hope this is of assistance...
Cheers
Rod