 Complete the following phrase:  Marshal of the Royal Air Force Samuel Charles Elworthy, Baron Elworthy, 23 March 1911  4 April 1993 was a senior officer in the Royal Air Force. He served as commander of a squadron of Blenheim bombers and then as a station commander during the Second World War. He became Chief of the Air Staff in the mid-1960s and implemented the cancellation of the TSR-2 strike aircraft and the HS681 military transport aircraft programmes. He also became Chief of the Defence Staff in which role he oversaw the evacuation from Aden in November 1967 and had to respond to the growing 