National Archives technical info on the Merlin

The National Archives have a lot (and I mean a lot) of specifications, maintenance guides, failure mode reports, etc, for the Rolls Royce Merlin 100-series and earlier, some of which might actually still be classified.

I've obtained a few of these documents, by requesting scanned copies, but it's going to be pricey getting those that are released. National Archives is cheap, but the last file I grabbed (AIR10/4872, released to the public in 1979) had 113 pages.

Has any author actually obtained and compiled the publicly released files somewhere? There's a lot of really good stuff in there, but the cost of getting all the material is prohibitive.

Far as I know, the Rolls Royce Heritage series does not include information from these files, but I could be wrong, that happens a lot.

Hi imipak, welcome aboard.

I have not run across any concentrated online source of such documents over the last 20 years that I have been crawling along the web. I have run across occasional individual records from people who have visited the various archives.

You could maybe try Calum Douglas at his website. He has spent a fair amount of time in various archives and might be willing to trade info.

PS If you do order any files from the archives, would you let me know what the approximate costs are for a couple of them, maybe for a smaller file and a larger file? I am planning on ordering some files myself and am looking for intel.

Whoops! Just noticed that Tony Kambic suggested you check out Calum's book in the other thread you started "Curiosity question on WW2 piston engine designs".

In another thread, Calum stated he uses this service to get copies. The costs are on the page.

ThomasP said:

Hi imipak, welcome aboard.

I have not run across any concentrated online source of such documents over the last 20 years that I have been crawling along the web. I have run across occasional individual records from people who have visited the various archives.

You could maybe try Calum Douglas at his website. He has spent a fair amount of time in various archives and might be willing to trade info.

PS If you do order any files from the archives, would you let me know what the approximate costs are for a couple of them, maybe for a smaller file and a larger file? I am planning on ordering some files myself and am looking for intel.

Whoops! Just noticed that Tony Kambic suggested you check out Calum's book in the other thread you started "Curiosity question on WW2 piston engine designs".

Click to expand...

It costs £8.40 to do a page check (ie: to see if the information requested is present and how many pages are involved).

Digital copies are then £1.20 per image for A3 size, £8.45 if extra-large (which usually won't apply here).

Paper copies are £1.35 per page (B/W), £4.95 per page (colour).

The 113 pages I downloaded from that file cost £128.40 for the scans, in addition to the £8.40 page check.

I would prefer it if others didn't have to put down such a chunk of change for files I already have, and I'm sure the National Archives would rather not scan in so many pages vast numbers of times, but it would look like they're under crown copyright until 2071.

It might be possible to request the files be released under open government license, as they are historically interesting and likely valuable to those studying WW2 engines.

There's 497 files in the archives relating to Merlins, 50 of which are post-1950 updates. This is a treasure trove of information, here's a selection:

AIR 51/373/19 - Merlin engine policy
AIR 10/2524 and AIR 10/2526 - Merlin XII Aero-Engines
AVIA 38/676 - Machine tools: Merlin engines
AIR 10/2539 - Merlin Mk 60 & 61 with addenda for Mark 62 and 63 Schedule of Spare Parts
AIR 10/2547 - Merlin 76 with addendum for Merlin 77 amendments only
AIR 14/2259 - Merlin engines: tests and trials
AIR 10/5157 and AIR 10/5158 - Reconditioning and salvage: Merlin engines
DSIR 23/7187 - Water injection experiments

Frankly, if someone tried to order 497 files, some of which will again be 100 pages or so, the country would go broke under the quantity of caffeine the poor secretaries would need.

I'll try ordering a smaller file, but the sheer quantity of data is terrifying.

Simon Thomas said:

In another thread, Calum stated he uses this service to get copies. The costs are on the page.

Document Copy Service

Independent research undertaken at the British National Archives (TNA) and document copying service. Specialising in military history, family history and Genealogy.

www.arcre.com

Click to expand...

Thanks, that's a lot cheaper than the national archives, for the volume of documents they have. As I've noted above, they have a lot of stuff.

I'm a little concerned, because the Merlin and Mosquito files seem to be crown copyright rather than OGL, but I'll talk with Calum and see what the status is.

imipak said:

it would look like they're under crown copyright until 2071.

It might be possible to request the files be released under open government license, as they are historically interesting and likely valuable to those studying WW2 engines.

Click to expand...

Hi Imipak and welcome to "information central".

There is great info here though, as with anything on the net, you will have to filter it. Your input already shows you will be a valued member.

I strongly request a forum member who has UK legal training read The Copyright, Designs and Patents Act 1988 as amended and the information contained on Archives page OL framework to confirm or reject my belief that there is no copyright on any documents that the Archives reproduce. That page covers a number of other items.

My belief comes from this document which I downloaded from OGL at The National Archives.



There is more to the document.

I got an email this morning with a link to this source of mainly downloadable NON PRINTABLE RAFM Hendon manuals. Homepage :: Military Library Research Service

They do supply a link to printed copies available at Welcome to Caliver Books but I did not follow it.


There is a small selection of airframe manuals such as these

The Spitfire manual is on CD apparently and there is no indication of the quality (dpi) of the scans.


There is a large selection of weapons pubs such as these and they are under multiple headings in the side bar

Update:

AIR 10/4879 (Merlin 130,131,134 and 135: Modification and amendment lists) has 232 pages and costs a small fortune. Ordered it anyway and will just cut down on eating for a while. However, for anyone interested in the Merlin, this and the 113 pages I'd got from the National Archives first time round can be regarded as the definitive final state of the work on the wartime Merlin engines, I'd have thought.

DSIR 23/14063 (Twin-engined Hornet fighter aircraft nacelles: high speed wind tunnel tests) has 12 pages and seems to be identical to AVIA 6/10638, even though their descriptions imply that they contain different information.

Rolls Royce Heritage very kindly got back to me about the heritage information in the National Archives.
Peter Collins very kindly informed me RRHT is working in a project with AHUK (Aviation Heritage UK) on getting heritage information scanned in and made more widely available, but from the costs the National Archives are charging, it looks like this project may still be in its infancy. That isn't particularly helpful, I know, but it's all he was able to tell me.

Arcre never got back to me about my request, and their website doesn't seem to have any updates post 2022, so if anyone knows any more, that would be helpful.

Some info on the "other" Merlin.