Originally Posted by
Nyghtwing
Although the vast majority of BA flights operate in and out of T5, there are a few destinations that operate out of T3 due to aircraft type (757's) and the lack of containerisation for baggage on this aircraft. This makes them incompatible for advanced T5 baggage system at the moment. Destinations include Barcelona, Madrid, Helsinki, Lisbon, Vienna, Malaga.
I believe the BA joint venture routes are all in T3.