I think it's fair to say that until recent times, beyond that 10-mile limit, which doesn't necessarily have a deep scientific basis, typically there were not issues because the aircraft were at sufficient altitude that the noise hadn't been an issue. That may be part of what's changing, with increased sensitivity. And the recent experience of Nav Canada has shown us that.
But today I don't think we have anything in place to deal with the noise beyond those airport responsibility limits.