Originally Posted by
gcuk
I'm not sure this info relates to LAX. American operate out of T4, T5 and the satellite terminal commonly referred to as Eagle's Nest. The occasional domestic flight also operates out of TBIT. Ignoring the latter, there is an underground tunnel connecting T4 and T5 which takes no more than 5 mins to walk through. There is no tunnel or long walk to the satellite terminal. Shuttle buses from T4 and T5 take you to the Eagle's Nest. If your flight is on American Eagle (CRJ or E170) it will leave from the Eagle's Nest. American mainline will leave from T4 or T5 (or rarely, TBIT).
You're absolutely right - the walkway under the runway connects to T5; the "Eagle's Nest" satellite requires a bus transfer. The first digit of a gate at LAX indicates the terminal, so Gate 49 operates from T4 and Gate 50 operates from T5. Don't be fooled into thinking Gate 49 and Gate 50 will be close together - it's a longish walk from the T4 lounge to gates in the 50s.