Distance from John F. Kennedy to Penn Station?

The AirTrain doesn't go to Penn Station. It's just a shuttle that takes you from JFK to the nearest subway stations (the Howard Beach Station on the A train, and the Sutphin Boulevard-Archer Avenue station on the E train and the J-Z line).

The Howard Beach station is much closer to JFK (you'd only go to the Sutphin-Archer station if you need to take the E or J-Z). You can take the A train to Penn Station, so get off the AirTrain at the Howard Beach station.

Then take the Manhattan-bound A train from Howard Beach to 34th Street-Penn Station. The ride on the A train is about an hour to an hour and fifteen minutes. The AirTrain takes about ten minutes. So you're looking at about an hour and a half trip from the airport to Penn Station.