Thank you for all the replies everyone - much appreciated.
The rear gunner of JD469, George Forster Cairns, was born in Longframlington, Northumberland. He was awarded the D.F.C., which was gazetted in the London Gazette on August 1st 1944. The citation specifically mentions this action:
"As air gunner, Pilot Officer Cairns has taken part in a large number of sorties and has displayed a high standard of skill and determination throughout. On one occasion he was a gunner in an aircraft detailed to attack Leverkusen. On the homeward flight the bomber was intercepted by 3 enemy aircraft. The first attacked from astern below but was struck by an accurate burst of fire from Pilot Officer Cairns's guns and fell to the ground, where it exploded. Almost immediately the second fighter closed in. Pilot Officer Cairns met it with a devastating burst, setting one of its engines on fire. The third enemy aircraft then flew off without attempting to attack. In this spirited action this gallant gunner defended his aircraft with exceptional skill. He has invariably displayed a high standard of courage and devotion to duty."
There's an account of the night's action here, written by the Navigator of JD469, Tom Maddock:
http://www.102ceylonsquadron.co.uk/memTomMaddock.html
Cairns also claimed a single-engined fighter over Berlin on January 20th 1944, flying with the same crew in Halifax HX153 DY-U. Time was given as 19.36 hours at 18,000 feet, heading 165º. The fighter was last seen by the Second Pilot
'diving below the Halifax in flames.'
Regards
Simon