By William Preece

updated 7:47 p.m. ET March 26, 2008

As BA transfers more than 70 percent 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 and by the launch of Continental, Delta, Northwest and US Airways transatlantic services at Heathrow as the "Open Skies" treaty between the U.S. and the European Union comes into effect on 30 March. Previously, only a few carriers could fly between the U.S. and Heathrow.

Terminals organized by airline alliance
The airport is being reorganized 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, seamless connections and to reduce costs and share facilities such as check-in and lounges.

Star Alliance airlines (including bmi, Lufthansa, Singapore, United and newcomer US Airways) will move to Terminal 1 (T1).

Terminal 3 (T3) will host Oneworld members (including American, Cathay Pacific and Qantas), as well as Aer Lingus, Virgin Atlantic and those BA flights that can't yet be accommodated at Terminal 5.

Terminal 4 (T4) will serve SkyTeam members (including Air France, KLM and newcomers Continental, Delta and Northwest) and non-aligned airlines.

Terminal-transfer timetable
The transfer timetable is complex and passengers will be well advised to double-check their departure (and arrival) terminals very carefully before travel.

The two train services from Heathrow into central London, the non-stop Heathrow Express and the multi-stop Piccadilly Underground service, share a dedicated subterranean rail station at T5.

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After T5 opens, Heathrow Express will serve terminals 1, 2, 3 and 5 every 15 minutes from Paddington, linking from the other terminals to T4 with a half-hourly shuttle service. A new service on the Piccadilly Line will provide direct service between the airport's central T1, T2 and T3 complex and T5, bypassing T4, while the existing service to T4 will be unchanged. So, again, check your terminal carefully before travel.

The existing terminals at Heathrow have been operating far above their intended capacities for years. But, with the opening of T5, 26 million fewer passengers a year will be using these dingy, overcrowded facilities by mid-summer. This will provide unloved airport operator BAA with room to start a much-needed overhaul, but it will be many years before all of Heathrow's terminals are world-class.

T3 is already in the middle of a $2 billion improvement program to bring it up to standards similar to T5, and T4's check-in facilities and departure lounges are also to be extensively refurbished by 2009.

T2 to be demolished
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.

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So, for passengers not traveling through 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.

Passengers will bear the brunt of the re-building bill following a UK Civil Aviation Authority ruling that airlines using Heathrow will have to pay higher landing fees. This will be reflected in a $6 fare rise for passengers from 1 April.

BAA, majority-owned by Spain's Ferrovial since August 2006, has been trying to raise GBP 11 billion ($22 billion) to repay existing debt and fund its capital expenditure program by securitizing its three London airports. But the global credit crunch has made this impossible for BAA and its only sure way of avoiding running out of cash is to charge captive passengers more, a tactic likely to be repeated over the next five years.

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