> A flight which does not start or end in the USA rarely has the need to fly over it. Europe/Asia - Central America would and not much else -- and there are ver

> A flight which does not start or end in the USA rarely has the need to fly over it. Europe/Asia - Central America would and not much else -- and there are very few such direct flights, mostly only to Mexico City. How about Canada to Central/South America? There are nonstop flights from Toronto/Vancouver to several cities. There are also flights from Canada to southern Europe that pass through the US. Even flights within Canada (Toronto to Vancouver) pass over the US. And routes from Canada to Asia fly over Alaska.