Royal Navy carriers entered the war short of aircraft

Could Royal Navy carriers in 1939 have carried more aircraft if the aircraft existed?

Yes; several sailed at about half their potential air-group strength because the Fleet Air Arm lacked enough aircraft at the start of the war.

Carrier capacity on paper did not guarantee an available air group at mobilization. Ships capable of operating around sixty aircraft sometimes sailed with roughly thirty in 1939. The shortfall reflected peacetime production and the time required to expand Fleet Air Arm units. As wartime output increased, the same hulls could use more of the capacity already designed into them.