Sorry to drag this one back after a couple of months, but for those who aren't familiar with LAX, a bit of assistance please: my father is flying LHR-LAX (BA) then connecting LAX-SAN (AA) on Saturday. It's one ticket, but he is fully aware that he has to clear immigration (and from above US Customs) in LAX.

From there is it the usual route of dropping bags immediately after customs at some kind of 'recheck' area with AA? What then for security? (I've seen some nightmare TBIT photos online with regards the TSA).

Assistance on this one is very welcomed.