Roy Chadwick / Bill Thorn plaque – RAFM Hendon

I wonder if any future visitors to the RAFM at Hendon could answer this question for me.
On July 6, 1976 a plaque commemorating the genius of Roy Chadwick and Bill Thorn (Avro’s Chief Test Pilot) who died when flying in the Tudor II in 1947 was unveiled by Sir Ralph Cochrane.
The plaque was placed on the floor below the nose of the RAFM Lancaster PO-S, Sugar.
The event was attended by members of the Chadwick and Thorn families as well as Lord Elworthy, Sir Barnes Wallis, Sir Arthur Harris, Sir Harold Martin, Group Captain Leonard Cheshire VC and many former members of Bomber Command including representatives from A V Roe and Rolls Royce.
This was a big event which included lunch for the invited VIP’s and was followed by a short display by the BBMF Lancaster, PA474, flying from Coningsby.
Can someone tell me if the plaque is still there?
Many thanks,
Ed