No. 9 Air Gunnery School was the first tenant of the base when it opened at the end of January 1941. It was equipped with Armstrong Whitworth Whitley bombers and Avro Anson training aircraft. Two days after flying commenced, the airfield was attacked by a single Junkers Ju 88 bomber that strafed the airfield, damaging one Whitley. Airspeed Oxford trainers from No. 11 Service Flying Training School were deployed to Llandwrog in mid-1941 to complete its students' night flying requirements. The following year, three of its Whitleys were deployed to RAF Driffield to participate in the first "Thousand Bomber" raid on Cologne, Germany on the night of 30/31 May 1942, although one aircraft failed to return.