cj241101 in India at the moment but will look in the suitcase under the bed- might have a photo of 'YSI that Sunday afternoon. Also remember a Super Connie (Rugby supporters for the Five Nations) and Channel Comet that day.
"707s were practically unheard of"
Maybe but like me surely you remember the odd 1970 Saturday afternoon Palma by British Midland- was it regular or a One Eleven replacement - can't remember
And your memories of the YSI colour scheme were correct. Do you recall it was the first aircraft in the new BY livery- when we sneaked a look through the door to H86 from "spectators" we wondered what all that red was about.