[Observer1940]

Hello Richard

I did a search of TNA, Kew Catalogue under "Rolls"; also "Royce"; plus "R.R."; "RR"; engine*; "Merlin"; "Rolls AND Royce" aircraft manufacturer and I; II; III; - X - etc., etc., and I recall getting a fair list of files to go at.

Also the Aircraft handling trials in AVIA 18, e.g. a search "Whitley" and the other aircraft types etc. I know the Whitley has an accident where the engine burnt out while under trail, setting fire to the aircraft.

Try Accident Cards at RAF museum for the RAF numbers given the engine, usually an engine failure with forced a landing was an 'L17' Cause and many A.M.1180 cards record the RAF number too. Can't get many engine numbers for my Whitleys of interest though!
You need to try under AIR, AVIA, SUPP (Ministry of Supply) and I think DEFE, or leave the Series blank.

The Whitley V with Merlin X engines is an interest of mine and I could never get any response from the R.R. Archives at all. Although I had heard that researcher/s were getting access to a massive engine Card Index somewhere. Rolls Royce failed to reply.

However, what I did discover was:-
i) Merlin X was overheating during early to mid WW2 due to loss of coolant and then the engine was catching fire, some of which were attributed to a faulty block (internal coolant circulation ways) and some of the other failures being thought due to the coolant system not being filled fully, with the suspicion that the Whitley coolant levels had been checked / topped up on sloping ground.
ii) I also noted that not all Pxxxx Whitley A.M.78s record the engine numbers given them by the RAF and I see Andy above has discovered this problem too.
iii) Jerry is quite correct above, that the engine serial number given by Rolls Royce was different to the number given the same engine by the Royal Air Force.

I have managed to find lists for the Whitley Merlin for January, February and March 1943 which gives both (R.R. and R.A.F.) engine numbers, with an RAF aircraft serial too, along with hours flown and when the block was changed, date of pressure tests and block change and whether done by Service; R.R. Crewe or R.R. Glasgow.

I found some other stuff in one of the TNA, files, a massive file (so big you had to take a long time to turn over the pages carefully) which included correspondence from MAP, along with some occasional references to crashes where the engine was thought possibly to be the cause.

It was Air Ministry Regulations that both the Engine and Airframe Log Books were to be retained permanently. But so far I have only been able to find A.M.78s.

PM me your email and I will forward some scans (6-7Mb) to start you off.

Mark