In late 1941 with Japan entering the war, the proximity of RAAF Evans Head to Brisbane made the base an important defensive asset in the event of an attack. As a defensive measure, 19 gun pits on the aerodrome equipped with .303 calibre Vickers machine guns were constructed. Aircraft from the base were also engaged in coastal surveillance duties. As many as 17 transportable Bellman hangars were erected on the base, and a substantial marine search and rescue unit operated from their own wharves in the nearby township. Other facilities at the base included accommodation for up to 1400 personnel, a hospital, garbage and sewerage services and recreational activities.