Originally Posted by
Moomba
Not just flights from London. Any transatlantic flight on AA including the ORD-DEL route.

ISTR that restriction was once US/UK only.
AA.com indicates the following:
- British Airways' transatlantic flights to/from the U.S. are not valid for AAdvantage mileage accrual or redemption.
[edit]
OK, it seems BAEC is far more restrictive with Transatlantic earnings on AA flight numbers than AAdvantage is on BA flight numbers: (
http://www.flyertalk.com/forum/8172634-post15.html)
One very important point - you cannot earn miles or Tier Points, or redeem miles when flying on AA transatlantic except on the (few) flights where BA codeshares with them to/from MAN. This is the same for AA people, they can't earn miles or redeem miles on BA services between the USA and the UK. However, they can on BA flights between the UK and Canada or Mexico. This is due to UK/US government restrictions.
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