I wasn't aware of the WW flight by HRH, but that possibly explains why some years later when i was CFI there and we had an event due to be attneded by another flying Royal that the security people primed us to have a tiger moth and instructor available just in case - which was needed. Although they hadn't covered every angle, as apparently the security head walked into the office and asked how much longer we were going to be and was horrified when the answer was that they had no idea since we had no radio!