[1] He was promoted to flying officer on 15 December 1960,[4] flight lieutenant on 15 August 1962[5] and to squadron leader on 1 January 1969.

[6] A Qualified Flying Instructor, in 1971 Johns trained Charles III (then the Prince of Wales) to wings standard on the Jet Provost.

[17] Promoted to air marshal on 24 February 1993,[18] Johns's next appointment was as Chief of Staff and Deputy Commander-in-Chief RAF Strike Command later that year.

[23] Johns became Chief of the Air Staff (CAS) in 1997 and was advanced to Knight Grand Cross of the Order of the Bath in the 1997 Birthday Honours.

[26] He was succeeded by Sir Peter Squire as Chief of the Air Staff and Johns retired from the RAF in 2000.

[1] Johns became Constable and Governor of Windsor Castle in 2000: he was advanced to Knight Commander of the Royal Victorian Order on relinquishing that appointment on 17 December 2007.