Practically all the Americans I have had the pleasure of meeting would always arrive at Heathrow and use onward road or rail transport from there and doubt very much if they use internal air transport. Where is Manchester I was asked a number of times when the aircraft we were on diverted there because of bad weather in the London area. Where is Leeds - I think most Americans would think Leeds was something attached to a plug!
P.S. I am a Yorkshireman.