 Johnson was given a permanent commission by the RAF after the war (initially as a squadron leader, although retaining his wartime substantive rank as wing commander, and later confirmed in that rank), becoming OC Tactics at the Central Fighter Establishment. After an exchange posting to the USA, he flew North American F-86 Sabres with Tactical Air Command and went on to serve in the Korean War flying the Lockheed F-80 Shooting Star. Johnson did not leave any written record of his experiences in the Korean War. It is believed he saw action against enemy aircraft. For his service he received the Air Medal and Legion of Merit from the United States.
