The picture was found by David Evans of Shrewsbury while clearing the house of Welshpool's Myfanwy Morris after her death.
As a young Miss 'Van' Jones she had served in the wartime ATS – Auxiliary Territorial Service – and seems to have struck up a particular friendship with one of the airmen.
And in trying to find out more about the photo she had kept for all those years David had a clue, as names were written on the back – bomb aimer Jock Doyle, then an unknown man, navigator Johnny, pilot Don, and last but not least, rear gunner Sammy.
That was enough for Rob, a researcher who has set up a massive Bomber Command database, to do some digging to see if he could come up with a match.
With such sparse information, and with the common use of nicknames among service personnel, Rob is making no claims to have solved the riddle.
"I can only find a very loose match for the names in the photo," he said.
"There are hundreds of other possibilities and with the source information so thin I can't identify them. I'd comment that the airman on the right is an officer and they are wearing battledress, but not dressed for immediate flying."
He says the best he can come up with is the crew of a Halifax bomber of 432 Squadron, which was a Royal Canadian Air Force squadron, based at East Moor airfield, near York. Intriguingly, Van served in York during her wartime ATS service.
The bomber took off on its fateful last mission on April 27, 1944, tasked with bombing railway yards at Montzen.
The crew that night was pilot, Pilot Officer H H Whaley; flight engineer, Sergeant A C Phillips; navigator, Flying Officer John Woollatt Burrows; bomb aimer, Flight Sergeant K J Doyle; wireless operator, Pilot Officer D C MacDonald; mid-upper gunner, Pilot Officer D A McCoy; and rear gunner, Pilot Officer Paul Edward Driver.
The bomber crashed not far from Liege and if the bomb aimer Flight Sergeant K J Doyle is the same Jock Doyle in Van's photograph, the good news is that he evaded capture, along with three other crew members.
The navigator and rear gunner were killed, and the flight engineer was taken prisoner.
However, the mystery remains unresolved, as there are things that don't sit well with Van's picture, which only shows five aircrew, whereas Halifaxes and Lancasters had a normal crew of seven.
Rob said: "Five airmen and one as a rear-gunner suggests a Wellington or Whitley bomber. And I can't see any 'Canada' flashes on the upper shoulders of the battledress, and East Moor – I've done an 'overnight' in the watch office (control tower) there – only operated Halifaxes."
He says the picture might, then, show a crew at an operational training unit, before they acquired a flight engineer and second air gunner.
Incidentally David Evans' connection with Van, whom he refers to as his mother or stepmother, is that she married the cousin who brought David up after his father died when he was aged two.