HF,
Imagine that your key inputs are moving an imaginary joystick. So, when you press NUM4 (that's the 4 key on your number pad) you are moving your joystick to the left one increment and the ailerons respond accordingly. If you were to press NUM2, you would be pulling back on your imaginary joystick and the elevators would pitch up accordingly.
Now, if you tap repeatedly on one of those commands, you are moving your imaginary joystick a great deal. For example, if you press the NUM4 key a dozen times or so, you are really pushing your imaginary joystick far to the left, which is going to cause your plane to start bank left sharply.
However, when you stop pressing key commands, your imaginary joystick is not going to center itself like a real joystick would. So, looking at our bank from above, if you took a real joystick and pushed it to the left until you were at a 15 degree bank and then let go, the plane would stay more-or-less at that 15 degree left bank until you gave it further commands. However, your imaginary joystick doesn't center itself just because you have stopped pressing the keys, so your plane thinks that you still want to bank left even further until it will eventually roll over and invert.
Of course, if you just pressed NUM4 twelve times in a row to bank left, pressing NUM6 twelves times in a row just to stabilize your bank angle and twenty-four times (!) to bank back in the other direction is really going to cut down on the precision of your control. One way you can help gain some control back is by using the auto-center ailerons and rudder command, which in the default assignments is NUM5. It isn't going to turn your keyboard into the latest Saitek flight stick, but it will act as something of an auto-center for your imaginary joystick.
Hope all that rambling made some sense and can help you at least a bit.
Good luck,
~Darrin
Simviation Forums
Flight Simulator and other chat
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