Concorde fleet have been grounded, drained of hydraulic fluid and their airworthiness certificates withdrawn. Jock Lowe, ex-chief Concorde pilot and manager of the fleet estimated in 2004 that it would cost £10–15 million to make G-BOAF airworthy again. BA maintain ownership and have stated that they will not fly again due to a lack of support from Airbus. On 1 December 2003, Bonhams held an auction of British Airways Concorde artefacts, including a nose cone, at Kensington Olympia in London. Proceeds of around £750,000 were raised, with the majority going to charity. G-BOAD is currently on display at the Intrepid Sea,
Concorde quoted as saying, "It is certain on present evidence and calculations that in the airport context, production Concordes will be no worse than aircraft now in service and will in fact be better than many of them." Concorde produced nitrogen oxides in its exhaust, which, despite complicated interactions with other ozone-depleting chemicals, are understood to result in degradation to the ozone layer at the stratospheric altitudes it cruised. It has been pointed out that other, lower-flying, airliners produce ozone during their flights in the troposphere, but vertical transit of gases between the layers is restricted. The small fleet meant overall