Layover at JFK

Please excuse my ignorance, but for such a short flight, why wait 3-5 hours at JFK, rather than take some sort of surface transport?

Not sure what you are looking for. Some things to consider at JFK, what terminal will you be flying into, out of? It will take time to move from terminal to the other. If you are in the same terminal, the 3hr layover would be fine. If you need to pick up bags, move to a different terminal, go through security again, that would be a lot.

It may be quicker to drive Newark and take an international flight from there, have you looked at that? If you reserve, $12/day, $16.50 otherwise. I don't think I would drive from Philly to JFK, getting from NJ over to Brooklyn/Queens can be a nightmare. It would depend on the time of the year & day. One good Friday, it took me 4hrs to get to NJ from Queens. You may be able to reach Newark airport by train a lot easier than JFK as well.

Mary

Especially for JFK, you really need to tell us what your itinerary is, what airline(s) and even better what terminal(s) at JFK you are considering -- it makes a big difference whether you have to change terminals at JFK, which are almost independent fiefdoms in and of itself. This is not a question that can be answered in generalities.

I'm with Joe here...why wait around JFK for 3 or 5 hours on the way home when you can just take Amtrak? This service will take you to Penn Station from JFK: https://www.nycairporter.com/schedule/pennstationtojfkairport/. And then Amtrak takes about 1.5 hours to Philadelphia.

British Air has flights that go from Edinburgh to London to Philadelphia. That might be another option for you, unless you're committed to fly a specific airline.

The inexpensive way to get from Edinburgh to Philadelphia would be to take Norwegian Air Shuttle into Newburgh, NY. You can catch a bus directly to the 42nd St. Station in Manhattan and then take Amtrak into Philadelphia.
The preferred option would be to rent a car one way dropping it in Philly about 150 miles south.. You will most likely be missing rush hour.

If you decide to do JFK to Amtrack- you can take the airtrain from JFK and connect to the LIRR to Penn Station, where you get Amtrack.

The inexpensive way to get from Edinburgh to Philadelphia would be to
take Norwegian Air Shuttle into Newburgh, NY. You can catch a bus
directly to the 42nd St. Station in Manhattan and then take Amtrak
into Philadelphia.

I would not recommend this as the buses do not leave often enough from Newburgh and it's a long trek to 42nd St especially if it's bumber-to-bumper traffic even before getting to the northern tip of Manhattan like on the Thruway, the Tappan Zee or the Bronx. Then from 42nd St, the OP needs to walk about a 1/2 mile to Penn through tourist-packed streets. The fresh air is a nice touch, however.

Pat, you don't want to do a layover at JFK if you're destination is Philadelphia ESPECIALLY if the layover means changing terminals. If you can't fly directly into PHL from EDI, do this:

1. Fly to JFK

2. Take Airtrain to Jamaica

3. Take LIRR (Long Island Railroad) to Penn Station

4. Take Amtrak to Philadelphia

Exception: If you have a 3 hour layover at JFK in which you STAY IN THE SAME TERMINAL to catch the flight to PHL, then do that over taking Amtrak. This should be faster than taking the train into Philly.