If the service number is from 1949 then surely this bag wouldn’t be anything to do with transporting RAF personnel to the Far East.

For information only, HMS Vengeance was refitted from August 1951 as a troop ship, departing Glasgow on 21/1/1952 with aircraft and men for Singapore. In June 1952, after refitting (again) as an aircraft transport, it left Portsmouth carrying aircraft to…Malta.
http://www.hms-vengeance.co.uk/vengitin2.htm

Displaying my ignorance, but knowing that some French aircrew adopted different (English?) names so as to avoid their families being the focus of the attention of the occupying Germans…might there be the chance of a Dutch pilot going for this as well?
If this was the case it might make things a little difficult, if it was not well publicised.

Twin engines?

In service pre 1950?

http://www.ww2aircraft.net/forum/album/unsorted/p8936-avro-lancaster-b-mk-ii.html

I am well aware of the (relatively few) Lanc mkII, just as there were (a lot more) Melin powered Halifaxes, but in the wider world the vast majority of enthusiasts picture a Lancaster with Merlins, not Hercules.

(Pedantic hat on) Thats not a Ju52… Its a Ju52/3m (the three engines are a bit of a give away!)

I’m wondering if the JMTU used any Valetta T.4 that was available.

The monograph gives it as the Javelin Mobile Conversion Unit (JMCU), a component of 228OCU, with ‘a simple Javelin systems simulator, servicing equipment, and some ground crew‘ loaded into a Valetta C1 and the rest of the team travelling in the Valetta T4. From that I’d say you’d have a better chance of assuming the C1 was dedicated to the JMCU and the T4 being whatever was available.

Without wanting to drag the thread off its interesting course the chances are that the vast majority of ‘missing’ aircraft went down in the seas around Britain. That being the case then there are many opportunities for inclusion in this thread listed on the Runnymede memorial.