Probably find it in something like \Data\CFG\airstrike.cfg or something similar, the game ignores different aircraft types and just assigns range to all airbases. You can see the range rings in the mission editor, for version 1.4 the file is \Data\Campaigns\Campaign\Jap_AirCover.mis, dunno what the friendly airfields in 1.5 would be.
Word about "range" the devs missed - the FW 200 Condor was the longest range aircraft the Germans had, max range about 2200 miles. In real life the military used "combat radius" instead of range, meaning how far a given plane could fly, spend 20 or 30 minutes running high speed in combat, then return to base. Obviously that makes more sense, if the max range is 2000 miles you wouldn't send it out for 2000 miles and let it crash when it ran out of gas.
So 2200 miles range actually meant about 1000 miles out to sea and back, more like 500-700 miles if they did any kind of search pattern. Our PBYs generally flew out on an assigned heading, turned and flew an arc, then returned to make a pie wedge. That's the main reason the frequency of air attacks in the original game was so silly, the Japanese simply didn't have that many aircraft with the necessary combat radius.
In real life same applied to the Luftwaffe, between 1937 and 1945 they only built 276 Condors. Donitz was constantly complaining he wasn't getting enough recon cooperation from the Luftwaffe, but they just didn't have enough long range planes.