W/Cmdr W. J. Harper was born on 22nd July, 1916. He was a Sergeant in the Windsor Country School Cadet Corps in 1930.

William joined the RAF on 12th July, 1937, and on 5th September was given a short-service commission.
As an Acting Pilot Officer, William was transferred to the reserve list on 12th July, 1941.

He was posted to 453 Squadron on 6th September, 1941.

William joined 135 Squadron on 18th April, 1942.

He was posted to 92 Squadron on 20th January, 1943.

On 15th September, 1943, William was moved as Commanding Officer to University Air Squadron in Leeds.

William moved to the Directorate of Operational requirements at the Air Ministry on 1sy January, 1946. He took an extended service commission on 28th February, and on 1st July, was promoted to Flight Lieutenant and took a permanent commission.

He was promoted to Wing Commander on 22nd April, 1949, and was placed on the retired list later that year on 22nd September.