Originally Posted by
FWAAA
The 43X designation should be reserved for internal use; publicly, it should be called 43. The 43X is relevant to pilots, ground crew and AA's operations personnel who schedule gate occupancy, but if you're inside the terminal, it's just gate 43.
You are right. If you happen to look at the ground when taxiing or pushing back from gate 43, you should see two yellow directional paths, and one will be marked 43X. These two paths guide the aircraft into the gate at a different angles. I am pretty sure that a 777 can't safely be parked on 43 due to its wingspan. They are designated differently so the pilots and ground crew don't pull in to the wrong spot, but passengers should only be told 43.
There are actually lots of airports that have this kind of different markings. JFK has a few gates like that from my experience.
AA does use remote gates (especially now with the fuel line project closing two gates), usually something like 210/212. I left from 212 today (47B, bused to 212). We were a 738, and there was an MD80 at the adjacent spot, so two flights were remote parked around 4:30-5 today.