six7driver, you obviously failed to read the preceeding threads...It is untrue that American authorities were opposed to allowing the plane to land on their territory.
Let me try to explain because some people are having a hard time wrapping their head around what six7driver said. He never said that the US refused clearance.
He stated that since no US airline can fly to Cuba, and this was a Canadian plane coming from Cuba, if it WOULD have landed on US soil, a potentially very messy situation for AT could have happened. Given the relation between Canada and the USA at this point, i would not have been surprised if they would have confiscated the plane, I'm not kidding.