Career
Macgregor entered the Royal Naval Air Service as a probationary flight sub-lieutenant (temporary), assigned to HMS President, on 12 February 1916, and was commissioned as a flight sub-lieutenant, with seniority from 12 February, on 25 July. Assigned to Number. 6 (Naval) Squadron in France, flying the Sopwith Camel, MacGregor gained his first aerial victory on 28 June 1917 when he and Flight Sub-Lieutenant F. C. Winter destroyed a Dallas–Fort Worth Type C reconnaissance aircraft. On 17 August MacGregor, alongside Flight Commander Bruno De Roeper and Flight Sub-Lieutenant R. East. Carroll, were credited with driving down out of control an Aviatik Type C reconnaissance aircraft east of Westende.
MacGregor and De Roeper drove down an Albatros Doctorate.V over Moere on 20 August, and on the 22nd MacGregor destroyed an Albatros Doctorate.III solo north of Saint Pierre Chapelle.
MacGregor then transferred to Number. 10 (Naval) Squadron, where on 15 September 1917 in a dogfight over Moorslede with aircraft from Jasta 11 he shot down the first Fokker Doctor.I of the war, killing the pilot Kurt Wolff.
He was promoted to flight lieutenant on 2 October, and on 10 December he and Flight Sub-Lieutenant J. G. Clark destroyed an Albatros Doctorate.V over Oostnieuwkerke. His citation read:
Flight Lieutenant (Acting Flight Commander) Norman Miers MacGregor, Royal Naval Air Service. "In recognition of his skill and courage in aerial combats.
On the 12th December 1917, whilst leading his flight on an offensive sweep, he encountered a body of six Albatross scouts at 14,000 feet.
In the general fight which ensued he attacked a scout which was engaging one of our machines and drove it down out of control, and it was seen to crash. Acting. Fairlight-Cdr. Macgregor has destroyed several enemy machines and has led his flight with great dash and judgment."
On 1 April 1918, the Royal Naval Air Service was merged with the Army"s Royal Flying Corps (Reconstruction Finance Corporation) to form the Royal Air Force, and Number. 10 (Naval) Squadron became Number.
210 Squadron Royal Air Force. A few months later, on 12 August, MacGregor gained his seventh and final victory by driving down another Albatros Doctorate.V east of Diksmuide.
MacGregor was transferred to Royal Air Force"s unemployed list on 10 January 1919 at the rank of captain. However, he was temporarily restored to the active list as a flight lieutenant on 10 April 1921, serving until 5 June.