Originally Posted by
anabolism
Weird that IB flights from MAD to LHR use T4, so the poorer lounge, but BA flights use T4S. Obviously, UK is not a Schengen country regardless of which carrier operates the flight. I know there are comments that say you can't use the T4S lounge when flying from T4 because of a need to pass border control, but that doesn't match my recent experiences in using the shuttle, and seems confusing that flights to the U.K. use both terminals, so why would there be different processes depending on the terminal?
It actually is construed as a BENEFIT, and in some senses it is. The IB-operated flights to/from LHR are an exception to the rule about T4 being for Schengen flights only. When you fly IB to/from LHR, you arrive at T4 and there is a small separate section at the far end of T4 with an EU passport control station immediately adjacent to the gate area. Upon passing through that checkpoint, you are AIRSIDE in T4. So, you can head right to your connecting gate with no further security screening. The airport authority allows it because all passengers have been screened in the UK to EU standards already, so there is no need to screen again. BIG benefit....I once was connecting to AGP and the only way I made my flight was that I was able to go straight to the gate after passport control. I made it only a few moments before boarding began.
By contrast, the BA-operated flights to MAD arrive at T4S. All passengers arriving at T4S who are connecting onward MUST pass through hand baggage security x-ray and WTMD because they could have mingled with passengers arriving from outside UK/EU/EEA who might not have been screened to European standards.
That's how best I understand it.
The drawback, of course, is that UK-bound IB passengers are not eligible to use the far superior Velásquez lounge.
I guess one way to approach it would be to fly IB metal when flying LHR-MAD, but then fly BA metal when flying MAD-LHR!