from TrimStab;
"I discovered recently on looking at the Canberra at the Solway Museum at Carlisle airport that the leading edge of the fin is wooden. This was apparently so that it could be more easily trimmed during initial testing. It would thus be relatively easy to add a bit to the leading edge of the fin if necessary."
My first job after Uni was with the Radar Research Squadron based at Thurleigh, it had just moved from Pershore. I was told that the person responsible for the wooden leading edge of the fin was the head of RRS at that time, Bob Rumsey, and that it was used to cover an antenna (possibly Decca?).
Years later I found myself joining MRF and working on Hercules XV208, finishing retiring from FAAM and the 146. Best job in the world for many enjoyable years.
Jim