t definitely had Royal Ordnance Factory derby on the side. I saw it. You do not need to be critical of our Observer. He was on the Flight Deck after all. He also found and nailed an Argie sub and helped rescue 16 SAS from a glacier - and all he got was a mention in despatches!Possibly the bomb was encased in Sheffield Steel, but assembled in Derby?
My commanding officer mistook Skyhawks for Harriers - maybe an Observer wasn't as observant as the job title suggests
I'd guess one of the guys getting an MiD whilst handling the bomb's disposal probably got a better look at it than a person unlikely to be employed in a damage control team.