As far as i know,the real-airforce or whatever it's called mod is included in both GW and NYGM so you should see aircraft.Try checking the map for air-cover grids and go right inside them and see if you get bombed.
I also scarcely see aircraft ,but i am playing in 1939 currently (i want to pass the war from start-to-end
),so i get attacked once-twice on patrol by some little fighter-bombers that don't even damage me .