Thanks very much for that - I have little concept of speed as I've not piloted for half a century and then only in gliders and a hot air balloon!
It must have been a nail-biter though the two personal accounts I've read of the journey before the shoot-down made it sound relaxed. I think after that it was by night and I wonder how they navigated other than dead reckoning or why, if night flights were possible, they ever did it by day. As the shoot-down was at 07:35 and about three hours into the flight it must have been a dawn t/o.
Thanks again, Colin