is there a way to modify the afcad and close rwy 13? I tried using FSX planner but no luck.
Yes, Flight1 AFX.
Good Luck! 
Thanks for the info. Will check it out.
AFX will certainly work, but Airport Design Editor (ADE) will accomplish the same thing, and then some. It's a much more powerful and comprehensive tool. It's constantly in developement by knowledgeable and enthusiastic people, and best of all its free. I definitely recommend it over the payware AFX. Keep in mind though, for ADE to work you'll need the Deluxe version of FSX.
My point about AFX vs. ADE aside, this is what afcad guru Jim Vile said a while ago about closing runways (he talks about VHHX but should still apply):
‘FS9/FSX uses a scoring system that we have been slowly deciphering the math to help us understand why some runways can be closed and some cannot.
VHHX is not a default airport in the database and it has to be built up with a AFCAD type design program. This gives us the ability to set the score for how a runway is utilized. If you remove the ILS from runway 31, delete the Start Location and close (set to FALSE) both the takeoff and landing element attributes this lowers the score for that runway so it cannot be called for over the Runway 13.
In return RWY IGS 13 will carry a high score even if the winds are tail winds and weather is less then 3 mile visibility.
The weather engine and the ATC engine have very close ties to each other so it is important we understand the relationship when trying to close a runway which may also have a ILS.’
--Anyways, good luck, shouldn’t be very difficult.
