One of my knowledgeable friends, Jean-Pierre Dubois, tells me that "this is one of the Lancasters overhauled and modified for anti-submarine warfare and maritime patrol
under a Western Union scheme and delivered to French Naval Aviation (Aéronautique navale) circa 1952"
Another piece of info that he forwarded is the following :
"The Lancaster was a Mark 1 LL864 "A4-H" which took off at 0027 from RAF Witchford, Cambridgeshire to destroy a communications target at Chevreuse. It was shot down by a night-fighter and crashed 150-200 metres of the Giverny
to Vernon road at Giverny where the crew are buried in the local churchyard..
This was one of six lost by 115 Squadron that night, all shot down by night-fighter, all making for the same target. Bomber Command overall lost 36-37 aircraft that night.
Bill Chorley, the acclaimed air historian, whose book "RAF Bomber Command Losses of the Second World War" Volume 5 (1944) this information is taken from, also adds a note:
'It was to Giverny that the celebrated French impressionist painter Claude Monet moved in 1883. Today, his famous garden is synonymous with his life and work, which many regard as the ultimate experience in this genre.'
And I have to say thank you to all the other anonymous contributors who have enriched this post and made this encounter of mine a very special one indeed.