Air Chief Marshal Allan Grant "Angus" Houston, (born 9 June 1947) is a retired senior officer of the Royal Australian Air Force and was the Chief of the Defence Force (CDF) from 4 July 2005 until his retirement on 3 July 2011. At the time of his appointment as CDF he was Chief of Air Force (CAF), a position he had held since 20 June 2001.