>>2027817That's what I don't get about this plan.
The closest sensible place to connect the two lines is the Otorii station itself, turning the two side platforms into island platforms with Tokyu line on the outside. But at that point you're less than 2km from the runway, so why not just tunnel under Kanpachi Doori all the way? Especially since every station on the joint portion will need to be rebuilt for separate platforms(see pic), which would be expensive because you're significantly widening 4 underground stations(Otorii, Tenkubashi, Haneda Terminal 3, Haneda Terminal 1/2). Sure, the terminus(Haneda Terminal 1/2) is 2 tracks 2 platforms so it would be getting rebuilt anyway, but I still think it makes more sense to go separately.
