JFK terminal 5 to 7
 

How long would it take to trasfer from Terminal 5 to terminal 7 at JFK? I will arrive from Washington at 720am and leave for London at 930? IS this possible??

There's an AirTram service that links all the terminals - the trains run every 3 or 4 minutes. Once on the tram, the ride between terminals will take less than 8 minutes.

FYI - the tram is outside the secure area so you'll have to clear the TSA checkpoint when you get to terminal 7.

You have 2 hours between flights, that's plenty of time. It should take you no more than 20 to 30 minutes from the time you deplane in Terminal 5 until you get to the TSA checkpoint in Terminal 7. This assume you are doing only carry-on or your luggage has been checked through to London and you already have your boarding pass for your London Flight. If you need to claim and recheck your luggage and/or get your boarding pass for the London flight it will take you longer but it is still doable in 2 hours.

I think that the OP has given us a bogus question. If OP were arriving at T5, that would be on JetBlue, and JetBlue does not have any arrivals from either Washington airport at that hour.

If in fact OP were arriving on JetbLue at 7:20, the connection would be far more problematic than RoamsAround suggests. I don't believe that JetBlue and BA have an interline agreement, so OP would need to wait for and collect any checked luggage, then take AirTran (not AirTram) from T5 to T7. And, the walk from the JetBlue terminal to the AirTran station is l-o-n-g and can easily take 10 minutes with luggage. So, while doable, if the inbound flight is on time, it's still cutting it close.

But all of that is moot, as I suspect that OP is in fact arriving at T8, on American, and not at T5. In which case the connection is a slam-dunk, because AA and BA do have a baggage agreement, so bags can be checked through.