An extension to the RAF Museum in Hendon, north London, will be opened by the Queen on 17 December, the centenary of man's first powered flight. It will house the key aircraft of the past 100 years. The £7.2m building, which has an area of 3000 m2 was designed by Feilden Clegg Bradley Architects with a simple barrel-vault and a series of internal mezzanine levels. Norwest Holst was the contractor, Buro Happold was structural and services engineer, Edco Design was landscape architect and Turner & Townsend was quantity surveyor.