I have a second hand copy of “The Bristol Beaufighter Crash log” compiled by David J.Smith-I found it second hand in MAMs bookshop. Interestingly this does not include this incident though it does record over 800 other accidents FF incidents to the Beau in UK. Jerry Scutts Crowood book on the Beaufighter mentions Beaufighters T4637 NG-O, R2073 & R2136 as aircraft flown by Chisholm-perhaps a look at the AIRBRITAIN RAF serial number books would give a clue (I think these were compiled from the aircraft record cards.