Tmmorris - my apologies, the 3 pints of Kingfisher meant that I had thought Chevvron had given the explanation!
Chevvron - no, not a WSO. There was an OC and and ex-OC on the squadron both wearing a VRT scraper. Not really interested in a 'witch hunt', it's just that your comments didn't accord with what I had seen. Anyway, all gone now.