Originally Posted by
LTN Phobia
No passport control as you are not entering the UK, but I am fairly certain that you will need to go through security at T3.
Indeed that's definitely the case, there is a Flight Connection process - just follow the purple and black signs - which involves a security screen but no passport checking.
You must check in your luggage, which at JFK they will do willingly, even on 2 PNRs. If you have to recheck your luggage at T3 I doubt you would make it. Or travel without checked luggage.
Note you will almost certainly be taken by bus from the T3 gate to the Prague plane, so you definitely want to be at the gate for 7.20 at the very latest.
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