Lordflasheart, nice one but HWs bone dome was a rear crew one without a visor or visor track. In the early 60s there was still the thought of not providing visors for rear crew in non-ejector seat aircraft.
Pontius - I wouldn't have made it up, I swear by my tattoo, but I will check with the erstwhile keeper of the noticeboard to see if I imagined it. LFH