Air Marshal Ian David Macfadyen, CB, OBE, RAF (born 19th February 1942), is a British retired Air Marshal who was the Lieutenant Governor of the Isle of Man until 14 October 2005. He was appointed following a successful career in the Royal Air Force.
Born the son of Air Marshal Sir Douglas Macfadyen, Ian Macfadyen was educated at Marlborough College and entered the RAF College Cranwell in 1960. He became a flying instructor and a member of the Poachers formation aerobatic team at the Royal Air Force College Cranwell in 1970 and was appointed Officer Commanding of No. 29 Squadron in 1980, with whom he saw operational service in the Falkland Islands, and Officer Commanding of No. 23 Squadron in 1983. He went on to be Station Commander at RAF Leuchars in Fife in 1985 and Commander of British Forces in the Middle East in 1990. Macfadyen served as the Assistant Chief of the Defence Staff, Operational Requirements (Air Systems) from 1991 and as Director General of the Saudi Arabia Armed Forces Project from 1994. He was promoted to Air Marshal in 1994 and retired from the RAF in February 1999.
He was appointed Lieutenant Governor of the Isle of Man in October 2000.
He was the National President of the Royal British Legion from 2006 to December 2008 and is now the Honorary Inspector general of the Royal Auxiliary Air Force. Macfadyen was appointed Constable and Governor of Windsor Castle in succession to Surgeon Vice Admiral Ian L. Jenkins with effect from 10 August 2009.