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Why the a/c tends to the left?

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Some possibilities:[ul][li]Asymmetric fuel load [li]Rudder off center. I know you said you're calibrated, but my Logitech digital stick wakes up off-center in roll. Don't know why, but fully exercising all controls fixes it. When the stick is unplugged, you could still have this problem. It is possible for keyboard input to rudder, and in keyboard mode, things stay put until moved again. Why don't heavies have this problem? Well, I rarely fly big jets, and heavies never, but I'd guess that small rudder inputs in them are relatively ineffective compared to the smaller airplanes. When your stick is unplugged (by which I mean, USB as well as power cords), if you still have the problem, try using the "center" controls key (5 on the numeric keypad with NumLock "off").[li]Yaw damper or autopilot heading bug setting?[li]Left-turning tendency: all real-world propellor-driven aircraft with clockwise rotating props (seen from behind) have a tendency to turn left at high power settings and high angles of attack (i.e., slow airspeeds). They are trimmed by fin offset to balance at cruising speed and cruising power setting. The fin becomes less effective at slower speeds, and there is more left-turn tendency at higher power settings, so on takeoff roll and during slow flight and stall recoveries, you'll have the highest left-turn tendency. There are four components of the left-turning tendency. In order of greatest effect to least, they are: P-factor, slipstream, torque, and gyroscopic precession. Gyro precession is only a factor when the aircraft is rotating about the lateral axis and relatively ineffective; mentioned here only for accuracy.Torque is the effect of the airloads on the prop creating resistance to it's rotation, which feeds back into the airframe through the engine mounts. IOW, the engine twists the prop quickly clockwise, and the prop twists the engine counter-clockwise. The whole airplane tries to roll left about the longitidinal axis and the pilot counteracts with aileron (or the wing incidence or aileron rigging is set to combat this). Aileron drag increases yaw on the lifted (in this case, left) wing, and the aircraft yaws towards the drag (left).Slipstream is the effect of the spiraling propwash rotating around the fuselage and striking the Vertical Stabilizer (VS) on its left side, yawing the aircraft left. If there were a symmetrical VS (as large on the bottom of the fuse as on the top), there would be no slipstream effect, as the force of the spiraling slipstream striking the bottom fin on its right side would generate a force that would balance that of the upper fin. P-factor is by far the largest contributor to left-turning tendency. A vector diagram is required to help you visualize this properly, but I'll have to try to get along without it. (There is probably one already on the Internet somewhere, anyway.) If you imagine the airplane proceeding at a 10

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ArleiGo to your aircraft config file and check the weights for station 1 and 2. When this happens to me I usually find I have a 170lb pilot and nothing to offset the weight in the right hand seat. When I counterbalance the weight It usually cures the problem.Does make a big difference in light aircraft. If you have tankage on each wingcheck to see that you have equal distribution. I've also found that to be the problem when I can't account for the problem for other reasons. Hope it helps!:-lol

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Hi Stephen,First of all, thank you for your detailed explanation about the possibilities for my problem.Yaw damper or autopilot head bug setting?No, this is not the case.I think my problem is related to rudder off center, as you said in your second bullet. To be honest, my joystick is not unplugged. It

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Give Microsoft tech support a call. I had the same problem. Tech had me delete a couple of files. He said they may have become corrupted..power surge etc. Sorry I can't remember which files they were. This definitely will solve your problem. Simster

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