So I went down to the UK National Archives in Kew today, armed with my list of potentially interesting files, as posted by overscan, and added to through some of my searching of the index.

As suggested, this was most certainly not a wasted trip. In the limited time I had available, and taking into account time wasted while waiting for files to be retrieved, I still got some fantastic information from previously secret UK files.

Some highlights...
1. Confirmation that UK and USA secretly shared knowledge on advanced armour development in the 1960s. The UK began sharing its knowledge of Burlington/Chobham armour with the US from 1964.
2. Suggestion that the US was not particularly interested in UK development of Burlington for most of the 1960s. UK officials took this to be a result of pre-occupation with Vietnam and MBT70 project.
3. Sudden resurrection of US interest in 1969 with request for possible full MOU. By this stage though the UK, seeing the failure of MBT70, was less than keen to cooperate with the US on armour development.
4. UK instead looked to Germany as a partner. After some worrying about German propensity to leak information eastwards (not entirely unfounded - see Markus Wolf's memoirs, for instance), eventual decision taken in March 1970 to share the Burlington secret with Germany. Aim appears to have been to get Germany to use Burlington in future MBT - Leopard II (then expected to be in service by 1975).
5. UK was at that stage looking to incorporate Burlington on a Chieftain chassis, to also enter service in mid-1970s. This project was (deliberately misleadingly) codenamed Chieftain Mk5/2. Advice was that UK could not afford to wait to develop an entirely new MBT to mount Burlington - so unsure were they about how long the secret could be kept.
6. Confirmation that Burlington offered superior protection against all known HEAT charges in 1970, and did not offer any less protection versus AFPFDS and HESH weapons than an equivalent mass of steel armour.

I am starting to upload the images I took with my shaky camera phone. Hope they provide useful information for all Tanknetters!

http://www.flickr.com/photos/30580098@N06/...57607331121461/

A fascinating glimpse into the development of Western compound armour! Thanks very much for sharing the information with those of us who live too far from such archives to do digging of our own.

(I particularly liked the reference to the S-tank's glacis array - already known to be present in 1970, but no details on the bar configuration yet...)

Interesting. They anticipated Bill-like downward-firing HEAT warheads for ATGMs.

Thanks for sharing. Fascinating.

Don't go away - it gets better!

Have uploaded another batch of photos onto the flickr site linked above...

still more to come as my time allows.

Thanks Jake! Christmas on September. I will wait when the whole set is uploaded. Fascinating information for a non/ill-informed civvie like me.

God bless Philippe Kahn and his phone cameras!


Great stuff, jakec! Many thanks for sharing. Internet is cool, books are interesting, but the sources are the essence.

DEFE48/240 'A study of future main battle tank options to replace Chieftain' is also well worth a look. Lots of different options were looked at, including the Anglo German tank project (which scored at the bottom of the list of options interestingly).

Incidentally, the ability to order documents for scanning is something I found very useful. I highly recommend their service if you cant make it down to Kew.

Have uploaded the last photos taken on my trip. I'm afraid one is blurred, but the rest are OK.

Plenty for the 'armour scientific' crowd in this tranche, including the planned array profile.

If I was a student/retired/unemployed I could spend days at the Archives. But sadly still have to earn a crust so will try to get back at some point in the future. Must work out how to game the laborious file retrieval system to get the most value out of my time there.

You know, I presume, about the pre-ordering facility (up to 3 files).

Otherwise, the main thing to do is to go to the card readrer screens or ordering computers about 25 minutes (or earlier if the place is not too full) and check your order status - as soon as your order is "on the floor" order your next batch. With a bit of luck you will keep gaining files instead of waiting for new ones.

If you are coming back the next day instead of handing your unread files back at the end of the day you can have them kept in your locker overnight.

I know it can be really frustrating if you order up three files expecting at least one of them to keep you busy for most of the 30-odd minutes til the next batch and finding them all to be only a few pages long.

.

Interesting.......

Aluminum/plastic framework with steel worked in.....kinda like the T72B turret armor...........

Davout

"Obsolescent M48's" indeed!

Oh, I forgot - they have changed the "bulk order" rules, and they MIGHT help :-


"You must order a minimum of fifteen documents from the same department and series of document up to a maximum of fifty documents if the numbers run consecutively, or thirty if the numbers are non-consecutive. However there is no guarantee that all of the documents ordered will be available. If you require large documents the number produced may be reduced in order to allow viewing in the reading room. "


.

Suprised to see that the classification has not been removed as normal

I think we are talking Chieftain 900 here as that was a Mk5/2 destined for persia but pulled from the line to be used as a guinea pig.

did i read this right?

"soviet secondary tank gun and artillery is anti-armour ammunition is fitted with HEAT warheads.
one possible way of increasing their effectiveness against BURLINGTON would be to develop a double-acting warhead.
such a development would take many years."

does this mean dual-warhead RPGs are effective against the passive chobham arrays?

I think that they thought it might be a possibility but I doubt that a small precursor warhead would do much.

Yes, I think they are alluding to full caliber charges in tandem arrangement. No such warhead exists to the best of my knowledge. I'm not sure if it ever has been seriously tried. The manufacturing process would be terribly demanding.

A nice touch to me was reading about the involvement of General Schnez. I was living next door to his grandson at university for a couple of years.

Well, strictly speaking the rearmost charge (2nd charge to go off, right?) is only 1/3rd of main charge diametre.........

Interesting to note, mention of 110mm cannon to possibly replace current 120mm. Stuart Galbreath has brought this up a few times in the past (your memory is not failing you mate ).

Excellent research Jake.
Thank you for sharing.

Charles

For once that is. We seemed to be seriously trying to get the Americans on board with it, but when they seemed more interested in the German 120mm smoothbore, we seem to have given up on it. I vaguely recall reading that there may actually have been 2 guns, one a smoothbore and one possibly a rifle. By 1976 they appear to have acknowledged that a new 120mm rifle was a more likely proposition. The 110mm is repeatedly mentioned in DEFE48/240 though, since the data for the wargaming results by West Byfleet was based upon it. Incidentally, document 48/1078 (comparison of comparative costs of MBT80, Chieftain and Challenger) not only gives the figures for the armour thickness in RHA of Challenger1 and MBT80, its gives the estimated effectiveness of the OE round (Operational emergency?) against T72 and T80. I really want to see that one in full.

Very many thanks for posting this up, though the excellent photographic quality of it made me feel a little like Kim Philby. Bob brings up the ChieftainMk5/2 as probably being Chieftain 900, would anyone be interested in me posting up the sales brochure?

Yes please.

Charles

Sorry ive taken to so long to scan, Ill try and get it done this weekend.

Been looking at the photos again (I didnt realise, there are actually 56 photos, and not 23 as originally thought!) and I notice the line drawings of the proposed Chieftain. is it me, or doesnt it look more like FV4211 instead of Chieftain 900?

The side drawing of the armour array is interesting. Looking at at the base turret, it looks similar to that of Challenger1.

Nevermind, found the 56!

Amusing how the proposed armour array in annex 3 resembles Leopard2A5 isnt it?

Note that they also propose fitting the no21 II commanders cupola. Interesting they also state a II gunners sight as desirable.

Interesting also the armour is concentrated on the hull glacis, rather than the bow area. Just like Challenger.

Great find and a great resource...thanks for posting the documents. TankNet does it again...

I'm a bit surprized the classification markings haven't been altered in the Archive version as well. Anyway, for me, the whole "...physical characteristics of the necessary components of the armor in order to enhance the efficiency of each of the numerous mechanisims, which acting simultaneously and/or in sequence, enable the armor to attack the leading part, the center, and the rear of the longating jet," is one of the most interesting passages.

For an interesting comparison with the Archive Burlington armor drawings, here's a diagram of Khafji armor: hmmm...


Shot at 2008-09-26

What is Khafji armor? T-55Enigma?

Yes.

Here at the pages converted into PDF.
http://rapidshare.com/files/151159856/Burl...mbined.pdf.html

Once again, very many thanks to the original contributor.