Some identified items: 3 – serial number plates

Peter’s suggestion regarding Air Ministry numbers has prompted me to send out a few e-mails to those who might be able to help with the radio/radar pieces. I have already had one response offering assistance but, as yet, nothing definite to report. Watch this space!!

“Just Jane” has been in the news over the last few weeks – on the BBC TV News and in the Sunday Telegraph. It therefore seems an appropriate moment to post a photo from the interior of NX611 taken on my visit to see her last year. What struck me (as seems to the case for everybody) was the comparison between the seemingly vast exterior of the aircraft and the cramped interior, where there was little room for movement – standing upright was virtually impossible except under the astrodome, and getting to the pilot’s seat by scrambling over the spar was not the easiest task, especially for my wife who was determined to sit in the position where her uncle had been seated all those years ago.

One of the photographs I took was with the help of torchlight shining down into the bomb aimer’s area. It shows the bomb aimer’s computer (at the bottom) with the rudder and elevator unit from the autopilot controls above. The aircraft was in the hangar and so light was a little restricted on an overcast day. How the crew coped at night with only tiny cockpit lamps to light their area gave some pause for thought.

This photograph is attached together with a picture of three of the serial number plates found amongst the wreckage. One of these is from the autopilot servomotor, and the others are from the Gee receiver and RF unit. The pieces of equipment themselves do not survive, or are unrecognisable amongst what has been found. Unless, of course, the Air Ministry numbered pieces I am trying to identify are parts from the Gee system.

A visit to the National Archives this morning was disappointing, but this did not come as a great surprise. The copy of AP 1086 available covered the initial issue in 1924 and the first 14 amendments, taking the record up to 1 July 1927. Neither I, nor the enquiry desk, could locate anything subsequently, so if copies do exist of versions of AP 1086 dated in 1943 or thereabouts (as seems likely), they would appear not to be at the National Archives. Someone, somewhere, must know something. Does anyone have any suggestions as to where one might be found?

I found AP 2893C on Oboe Mk.2 – Album Leaf, ARI 5582. This turned out to be quite a short document, so I copied it all, and now have this for reference, but it hasn’t helped with our mystery objects as it had no illustrations, just diagrams, and only brief details of the major components.

What was of great interest, was something not connected with the wreckage, but with the operation of ‘Oboe’ Lancasters which was something which I had also wanted to look at. There were lengthy exchanges of memoranda and some “Top Secret” Air Ministry correspondence. One note on 14 July 1944, just 6 days before ED908 was shot down, says; “As you know the P.F.F. have already carried out six blind attacks on two Crossbow [V1] targets with Lancasters and Mosquitos flying in formation, led by an ‘Oboe’ fitted Mosquito or an ‘Oboe’ fitted Lancaster. They fly in close echelon right or echelon left formation, the leader releasing his bombs with the aid of ‘Oboe’, and the remainder releasing theirs visually as they see the leader’s bombs go. They cannot fly in an ordinary vic formation as the aircraft on the near side of the ‘Oboe’ aircraft interfere with the beam.”

Consideration was being given to equipping a Pathfinder squadron with up to three Lancasters with ‘Oboe’ Mk.II. However, ‘Oboe’ could not be used in a Lancaster equipped with H2S, and so it was thought that it might be worthwhile equipping one flight of 617 Sqn which could not carry H2S because of its large bomb doors.

I believe that this proposal might have been put on hold after ED908 was shot down with, as far as I can tell, just one more ‘Oboe’ Lancaster led sortie shortly afterwards, until December 1944 when a similarly disastrous daylight ‘Oboe’ Lancaster leader attack took place against Cologne – again a combination of a 109 Sqn team in a 582 Sqn Lancaster. Flak and fighter aircraft resulted in two engines of the ‘Oboe’ Lancaster being set on fire, but the aircraft continued on the bombing run, dropping its bombs accurately, before it spiralled to earth. It is not difficult to find similarities between what happened at Cologne and five months earlier on a July afternoon at the Forêt du Croc. An account of the raid is set out in the Bomber Command War Diaries where it says that the 109 Sqn pilot, Sqn Ldr RAM Palmer, was posthumously awarded the only Oboe VC of the war.

Air Ministry equipment numbers

How wrong I was to assume that the existence of an Air Ministry reference number would lead to the ready identification of pieces found! However, after further research I have now established that the equipment ‘bible’ is AP 1086. It appears that I need Book 4 – Parts 1, 2 and 3. Radio, radar, telephone and telegraphic equipment. It is said that this is available at the National Archives, but I haven’t been able to locate it on the online index. The specific sections I need to identify the pieces we have found are apparently:

10AB – Miscellaneous radar equipment
10B – Radio and radar aerial and mast equipment and insulators
10H – Radio cable assemblies (connectors), disc indicating fuses, leads, plugs and sockets, holders and terminals

Does anyone have any further information about what can be found at Kew, or know how I can access these sections?

There also should, presumably, be an AP on Oboe, but I haven’t found a reference. Can anyone help please?

austernj673,

A little while ago (post #108) you asked for a link to the ordnance diagrams I had posted. I have since followed up a reference and come across the website below. You may have followed the same trail?

http://www.lexpev.nl/manuals/index.html

This is an index page with ordnance manuals from a number of countries. The only reference to copyright seems to be a request that the information is not to be used in any commercial product.

Somewhat counter-intuitively details of British Explosive Ordnance from WW2 is found not only under the heading ‘BRITISH manuals’ but also under the heading ‘US manuals’ because the US Navy Bureau of Ordnance produced a pamphlet on British ordnance in 1946 for its Bomb Disposal School under the reference OP 1665. This US pamphlet looks as if it covers most British ordnance used in WW2 – as might be expected if it was being used to for bomb disposal purposes!! Hope this will be of help.

………………..

Looking through the above manual, it is apparent that the ‘standard’ Target Indicator was 61.7 inches in length, and it was only the ‘specialist’ types – Multi-flash, Spot Fire, Photoflash, Skymarker and Seamarker – which were greater in length at 67.75 inches as mentioned earlier by Air Ministry (post #97). Another little loose end tied up!!

Reverting to my last post – there have been well over 100 views, but no comments. As far as I can tell, there were two types of ‘window’ – one was released in a long strip, and the other in bundles which were often released at appropriate intervals through the flare chute, because the motorised dispensers which were intended to be used proved unreliable?

The bit of a bundle of ‘window’, which is what we think has been found amongst the wreckage, seems to have a thin wire which might at one time have run through the hole that is apparent at the end of the bundle of strips, holding them together. Presumably there must have been some mechanism whereby, once dispensed, the strips were separated from each other to fall in a cloud – perhaps this was by using a small parachute (as for flares) and allowing the wind to do the work?

250lb TI Bomb casing diagrams

To add a postscript to the exchanges of the last two weeks, and with acknowledgements as previously, I attach two diagrams which appear to come from the same unknown original source. The first, on the left, shows the Mk I 250lb TI bomb (as before). The second, on the right, shows the Mk III version to which Air Ministry has referred, with its cast-iron weighted nose and tail fuze adapter. If both diagrams are scale drawings (as would be reasonably expected), then the Mk III version, with its lighter-gauge steel casing, is slightly wider in relation to its length than the Mk I version, which could explain some of the apparent slight variations in measurements which have emerged in our postings.

It is conceivable that the better preserved casing which has been found is the thicker Mk I version, and the more damaged one is the thinner Mk III version. However further speculation is unlikely to be productive – we seem to be agreed that what we have are two 250lb TI casings!!

Post-postscript: to complete the picture, I have just heard from France that there appears to be a collar on the piece to hold a tail plate, but no sign of rivet holes because of the corrosion. Très bien !!

TI Casing

Air Ministry, I have had a look at the narrative accompanying my copy of the TI diagram. As you say, assuming that we are looking at a TI 250lb casing with a tail fuze, the choice is between a Mk IC with a thick-gauge steel body, or a Mk III with a thinner body and weighted steel nose – do you have any more information about the thickness of the two casings? I have not managed to find anything.

I note also that the rivets holding the tail in place would shear when the bomb functions, and the tail plate would be forced off, so we would expect to find the casing without it. I cannot see any holes near the base on the photographs we have, but the rust from 68 years under the ground could well mean that the rivet holes are no longer readily visible.

You are still uncertain about the length of the surviving casing(s) for which we have no definitive measurement without the tail plate. I have therefore taken the TI diagram which I assume should be a scale drawing. If we assume the external diameter is 12.0 inches (your post #97), then the length of the casing to the point where it reduces in width on the diagram can be calculated as 31.5 inches or 80 cm (as shown on the attached), which is precisely the figure we have from France.

It should be mentioned that even the most intact piece is mis-shapen which will cause some difficulty in obtaining an accurate measurement of what it once was. In particular, the formation of rust on the surface would increase the circumference measurement to a little beyond the 95.7cm implied by a 12 inch diameter.

So, I would ask the question, if what we have is not a TI casing, then what other objects of about this size (with a diameter of approximately 12 inches and a rounded end) have a single suspension lug, a burster container with a flash hole, and a transit plug, which is what we seem to have?

Let us await further information from France.

austernj673, I found the diagrams on two different websites. Hopefully the following will take you to one image from which you can navigate to others:
http://uxoinfo.com/blogcfc/client/includes/uxopages/Mulvaney_Details.cfm?Ord_Id=FB70