And then of course, WWII night fighter pilots ate lots of carrots to improve their night vision. Nothing to do with the special top secret radar sets, now was it? My Dad laughed when he told me - he was a W.O. in the RAF, but then he died in 1969, and some of those secrets were still more or less 'secret' up till then, and many people took their secrecy oaths seriously in those days...