In reality RAF aircraft with homogenous armaments could not fire half the guns, they were all or nothing deals. Spitfire Mk Is, Hurricane Mk Is and Mk IICs, Typhoons and Tempests fired all of their guns when the trigger was pressed. RAF fighters with mixed armaments, such as the cannon and machine gun Spitfires and Mosquito FB.VIs, could fire thier cannon, their machine guns, or all guns.