Passur's airport monitor has the radar track of his Cirrus SR20 departing Teterboro, and then about ten minutes later has an aircraft going up the East River and turning around, then disappearing.
Go here:
http://www4.passur.com/teb.htmlSet the date to October 11th and the time to 14:30. The first aircraft that appears just north of TEB is the Cirrus. Click on it to see the tail ID on the right.
If you expand the view to 20 miles, you can see the aircraft turn down the Hudson river, then disappear (which is really the radar temporarily losing the aircraft due to the low altitude). You then see a "General Aviation" aircraft about the same position, presumably the same aircraft, track down around the Statue of Liberty and up to the entrance of the East River.
There are some confusing moments where aircraft targets appear and disappear, but around 14:39 or so, you see an aircraft going north up the East River, then turn around and disappear. The target never reappears.
