LGA also has an FIS facility. If they didn't, AC would not be allowed to fly in even with pre-clearence. Alaska learned this the hard way when they had a flight in the air from YVR-SNA and they were told they had to divert to LAX. In a message dated 7/11/2005 3:13:17 PM GMT Daylight Time, edwardwallace@xxxxxxx writes: Air Canada flies into LGA and they clear US Customs in Canada before boarding.