This mod focuses on stability of the autopilot and ease of operation during takeoff and landing. As such, it has been confirmed to fly at the speed of sound up to Mach 1.3, but not beyond. 
This change eliminated the slight vibration (appearance) of the elevator when cruising and provides a linear control feel. In addition, low-speed flight on autopilot is now possible.(However, when the aircraft is in gear up and making less than 200 knots, the nose of the plane tends to drop slightly.)   
The auto-flap is activated by using KBT_FLAP.xml.

Griffin G39 from Deimos Inc. is required.

If you feel that the original flight characteristics or gimmicks are compromised, please stop using this mod.

V1.4
The following two improvements have been made to the autopilot flight characteristics in this update.
(1) The aircraft traces the course of the flight plan without meandering.
(2) Vibration at sonic speeds has been reduced.

V1.3
The user can now choose whether or not to use auto-flaps on landing.
Spoiler ON and landing gear down" → Flaps ON.
Spoiler OFF and landing gear down" → Flaps OFF.
In other words, we have added an auto-flap trigger to the spoiler.
The air combat flaps operate regardless of whether the spoiler is ON or OFF. (Landing gear up state)

Issue 1
・Takeoff can only be done with flaps up.
Solution for now
・The aircraft has enough power and lift to, to put it in good perspective, "enjoy a good-looking takeoff that starts with the nose up.

Issue 2
・When the gear is up and at low speed and the flaps are active, gearing down causes the flaps up, even though it is at low speed.
Solution for now
・The stall occurs slowly and can be addressed. ”Maneuver without panicking”.：)

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

V1.2
The center of gravity position was made similar to that of the original Griffin. In addition, turning performance on the ground has been improved.

V1.1
This update improves the center of gravity, contact points, ground handling, and aileron rates. A version without flaps activated is included, since apparently takeoffs and landings are performed without flaps in Griffin's normal operations. Multiple versions exist, so please check carefully before installing.

How to install
Move the folder "aircraft-GripenFDEfix" that appeared after unzipping to the community folder. That's all there is to it.
Please do not overwrite the original Griffin or install individual files.