ABG - Absolutely nothing to do with your specific enquiry, but as it's a quiet Sunday morning I thought I'd just share these thoughts.
I first flew LHR-NAS in September 1969 as a 13 year old, on a BOAC VC-10 with a routing of LHR-JFK-NAS-KIN. The 'in-flight' routing information was a piece of paper passed backwards through the cabin, on which the Captain had hand-plotted our route across the Atlantic.
As an aside the VC-10 we flew on, G-ASGN (I used to be a keen aircraft spotter), was the very plane that was blown up near Amman 12 months later, almost to the day.
At JFK we (my mother and I - we were joining my father who had just been posted to NAS) - along with just a very few other transit passengers were loosely escorted from 'arrivals' to 'departures' which, I clearly recall, involved walking along a public sidewalk outside of the terminal without having gone through any Immigration or Security. How easy it would have been in those days just to mingle with the crowds and disappear. How times change.
I flew the route many more times in the early/mid-70s; travelling to/from UK boarding school. By then it was BA 707s flying LHR-BDA-NAS. I shared one flight with Earl Mountbatten.
I last flew LHR-NAS non-stop in 1989 on a BA 747 on a business trip; by then the journey had lost a lot of the romance.
Anyway, I'm beginning to sound like my grandfathers (both long since departed) so I'd better stop this trip down memory lane and shut-up!