How do I tailor flight characteristis of a plane?

[dyoung87]

I downloaded the Grumman Yankee aa1-a , but can't hardly get it to climb. My full size Grumman climbes at around 750 fpm. I opened the aircraft cfg. in NOTEBOOK  to make some changes ,but they wont stick and it does'nt make any difference in the way the plane flys . Any suggestions?  Thanks for your time.

[alan_harmi]

try downloading aired to edit the air file.
can be found here:http://www.simviation.com/fsdesign_utilities.htm