This doesn't sound like a controller configuration issue.
Aces High models WWII aviation very realistically, including forces such as torque from the engine. Engine torque will cause your plane to veer left if you do not use opposite rudder to help keep the plane straight on the runway.
Use the A and D keys as your rudder to "steer" the plane down the runway on takeoff. Also, if you do nothing by default, when you press fly the game will automatically takeoff for you. Be sure to let the plane stabilize and get some altitude before you take over control. Be sure not to touch any controls after you hit Fly or the auto-pilot will dis-engage. It will be difficult to fly with a gamepad, but it is possible.
Use the auto-takeoff feature to help get you started. Also, try a plane with less torque issues such as the P-38 at first.
If you need a hand, drop into the training arena and a trainer can give you a hand getting airborne.
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Lephturn - Chief Trainer
A member of The Flying Pigs
http://www.flyingpigs.com 
"My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
- Steve Earl
