Originally Posted by
Austin787
Two big advantages of WAS-PHL-Europe over WAS-LHR-XXX is avoiding a connection in LHR, and only having to go through airport security once instead of twice.
From a passenger point of view, sure, but less so from the airline's point of view: only to the extent that they lose passengers or revenue because LHR is the better option. I suspect that extent is fairly small, certainly small enough to justify a reduction in DCA-PHL capacity that has historically been used for WAS-Europe traffic. And, of course, HPdbaAA can sell WAS-LON nonstops for the London traffic, which pmUS couldn't.
(From a passenger point of view, if it's a 1-stop flight either way, flying out of DCA over IAD makes a bigger difference to me than transferring in LHR vs PHL.)