Concorde, the aircraft that until seven days ago flew faster than a rifle bullet, was yesterday consigned to the status of a museum piece after British Airways announced that it was too expensive to keep one of the supersonic jets airworthy.

The airline ended months of speculation and argument with those who wanted a Concorde to be kept operational for fly-pasts and special occasions by revealing that it was donating its fleet of seven of the aircraft for free as exhibits to museums and airports.

Three Concordes, valued at £1m apiece, will have perman-ent homes abroad at two mus-eums in the United States and the main airport in Barbados.

The other four will remain in Britain at locations including Filton, near Bristol, where the plane made its maiden UK flight, and Heathrow, where its final passenger flights touched down last Friday.

The decision ended hopes that one of the BA Concordes would be kept back by the airline in a joint venture with Airbus, which as Aerospatiale helped build the plane in the 1960s and 1970s, for ceremonial occasions and airshows.

Rod Eddington, BA's chief executive, said: "The technical and financial challenges of keeping a Concorde airworthy are absolutely prohibitive. Airbus has told us that they are unable to support such a project."

The airline said a feasibility study had found that the plane could only be kept airworthy with a permanent maintenance crew and fully-trained air crew. A safety document was due to expire at the end of the year and could only have been renewed at great expense, BA claimed.

Sir Richard Branson, who has led those campaigning for Concorde to stay airborne, called for an export ban to stop the jets leaving Britain.

In a separate move, the airline announced there will be a charity auction of Concorde memorabilia in December.