You should look at the airfields much more closely as they are hardly identical on Kashan or Qinling.
Granted that yes, they are very similar but no where near identical, Qinling even has two separate plane stand and taxiway models, one for each base.
ledo1222 wrote:Would you rather have the attacking force have a make shift Base.
Example* On kashan when the US Army is invading the runway would not be a real runway but on built like Bulldozers came in and quickly set it up so the jets could land.
Modern day fighter jets would never take off or land on anything that wasn't solid concrete. It would be very unrealistic for a fighter jet to take off from a dirt runway.
The only "make shift airbase" that would be some what realistic would be the use of a strait, flat, long section of road with no obstacles next to it but really there are going to be very few roads that fit that bill for anything other than STOVL aircraft which have very short take-off and landing requirements (hence the name, STOVL

)
ledo1222 wrote:I also know sometimes they can take and abandon one, but when have you ever seen 2 Military Air fields 4km that close, and other wise abandon?
No but we have to work in the constraints of BF2 which is the maximum sized map is 4km and as such, if we want both sides to have jets, we need airbases within 4km of each other, which yes dose suck since that is unrealistic and we know it but having jets on the battlefield outweighs the unrealistic side we feel.
Also don't worry, newer maps will address these issues more
EDIT:
ledo1222 wrote:When the US was taking back the pacific they build dirt Runways for there bombers to land. And that was after they retook the island.
WW2 aircraft didn't need to get up to such high speeds as modern fighter jets do to take-off.