As BA transfers more than 70% of its London Heathrow Airport operations to Heathrow’s new Terminal 5 (T5) on March 27, a giant game of musical chairs begins. Some 50 of the more than 90 airlines serving the airport will move terminals over the next 10 months.

The changes will be intensified by the transfer of some BA and all American Airlines services from Gatwick Airport to Heathrow as the Open Skies treaty between the US and the European Union comes into effect on 30^th of March. Only a few carriers could fly between the US and Heathrow.

The airport is being re-organized largely around the three major global alliances of airlines. Most of the airlines serving Heathrow belong to one or other of these alliances. When completed, this co-location will allow alliance members to offer smoother connections and to reduce costs and share facilities such as check-in and lounges.

The demolition of T2 later this year will allow room to build the initial phase of a new facility, Heathrow East, for the Star Alliance in time for the London 2012 Olympic Games. After the initial phase of Heathrow East is complete, T1 will be demolished to make room for a second phase.

So, for passengers not traveling through the T5, the next few years will be testing and unpleasant as BA’s competitors try to run operations in old, dingy terminals alongside major building sites.