Slow Biker (#210),
Not RAFG, but a similar occurence (Hawarden, 1942), recorded in my Post #2452 on "Pilots brevet", Page 124:
..."There was an amusing (for the bystanders) incident in which this Spit was involved. An armourer was tinkering with the firing button in the cockpit. A second airman walked past right in front of the aircraft when the cannons unexpectedly fired. As he was exactly in line with the nose, the rounds passed harmlessly either side of him and off to the Welsh hills. The gun camera (in the port wing root) still had film in it, it worked and this was developed. Seemingly, the prints clearly showed his hair standing on end!"..
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Danny.