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Geofa

Plane flight pulls/drifts to left

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Hi,Sorry if this should have been posted in the HW forum, but I don't think this is a HW problem and may be more a file that need to be edited or CTFJ (I remember the old program, LOL) or someting similar.I am using a Logitech Extreme 3D Pro Joystick in FSX. I recently upgraded from a joystick that did not have a "twist" rudder. I notice for certain Aircraft after I uncheck Autorudder in settings, the plane will not fly straight, it continues to pull/drift to the left. The included Cessna 172 is one of the worst, the Baron also drifts to left. I don't see a rudder trim adjustment in the cockpit for the C172 at least, so flying level is a constant battle of twisting rudder/turning back to the right. It may fly level about 15 seconds, then drifts to left more and more. I also have the FSD Saratoga add on, it does much better when autorudder is unchecked in settings, so it doesn't seem to be a calibration problem (I have tried re-calibration).Is there an edit/change/calibration so the C172 or Baron will fly better with Autorudder setting unchecked? I can fly these AC with the autorudder checked- they will then fly without constant pull to left, but "twist rudder" doesn't work as well, it is more muted (and the ball in artificial airplane doesn't work at this setting.TIAWilliam

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That's as it should be. Torque will have to be adjusted for constantly by some rudder.And of course there's crosswinds as well.Of course if your controls are improperly callibrated that could make it worse.

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That's what aileron trim and rudder trim are for... to compensate for the engine torque.

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Try flying a small (or large) jet. Those aircraft won't exhibit torque. Or try flying a twin prop aircraft. If you are still moving to the left, either you are experiencing a wind issue or more likely a controller issue. That happens. I was testing out Eaglesoft's Liberty XL2, and dag-nab it if she wouldn't climb. I knew the Liberty was supposed to be an agile flyer, so I discovered an error with my joystick.If all else fails, you can reduce the P-Factor and Torque sliders in your Aircraft Realism settings. If you have the money, invest in some rudder pedals. Non-flight simmers immediately either laugh at your extravagance or else think they are ergonomic footrests, but good rudder pedals really help Flight Sim, and you'll own the skies when Oleg's Battle Of Britain eventually comes out. Jeff ShylukAssistant Managing EditorSenior Staff ReviewerAVSIM

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Thanks for all comments. Yeah, I would like to get rudder pedals one day. I believe the joystick is calibrated properly as the supplied SW from Logitec shows graphics that shows proper centering of the x and y axis and rudder. Plus, it flies level with autorudder checked, so x and y are good. I does seem a little wierd that flying level with no wind (and no autorudder) requires almost constant input to turn back to right though, or the plane will always end up in a left spiral turn (eventually a 360 degree turn I think). I do notice pull to left a little on the twin Baron, not as much as the C172 though. I think last time I tried the P51, it was almost unflyable as the pull to left is extreme. I am gonna fire up and see if P51 has a rudder trim knob, I couldn't find rudder trim knob for the C172. I am going to go try the Lear, also, ie no torque from engine as sujjested. And, in the Baron, if I adjust the rudder to 1% positive, it seems to be slightly too much, and it starts drifting to the right. I will experiment with the torque/pfactor sliders as you suggested. For those that actually have pedals - If you fly the C172 (in No Wind) with rudder pedals (no autorudder checked no settings), does it continually require turn to right rudder corrections about every 10 to 20 seconds to fly anywhere near constant heading? William

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The C-172 does not have a rudder trim knob in the cockpit. The real world C-172 have a small bendable trim tab on the rudder. I had to change many a trim tab on rental C-172s. Not many of them flew straight.

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>For those that actually have pedals - If you fly the C172 (in>No Wind) with rudder pedals (no autorudder checked no>settings), does it continually require turn to right rudder>corrections about every 10 to 20 seconds to fly anywhere near>constant heading?As mentioned below, the 172 has a ground adjustable trim tab. The idea is to get the tab adjusted for straight flight at cruise speeds. It's not something that will be changed back and forth a lot. You'll need right rudder for the takeoff roll and climb.Personally, if I didn't have pedals, then I'd use auto-rudder, as I don't like twist grips. For long flights, I prefer the auto-pilot, as trims are a bit touchy, and the desktop monitor's field of view for the horizon get's somewhat annoying if you look at it too long.L.Adamson

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Hi William,Has anyone mentioned adding a passenger and monitoring your fuel usage? Most small default GA planes have only the weight of the pilot included. This makes the plane turn left unless you edit the aircraft.cfg file and add weight (170 pounds) to the right seat. Also insure that the right fuel tank only is not selected. I've noticed on the Mooney particu;arly, that you must constantly manually alternate the tank selector or you bank one way or the other.R-

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Good catch, Ron! I forgot about that one.Jeff ShylukAssistant Managing EditorSenior Staff ReviwerAVSIM

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Just to confirm this is very sound advice: spreading the weight did the trick nicely for me. Search here for "aileron drift", I think that was my original post here about the same problem. Fixed altogether by weight redistribution.Somebody also suggested to me that for longer flights I should just use the AP. I thought it madness at the time, since I wanted to feel I was flying the thing. Some time later, I know exactly what that poster meant. Heading Hold sorts the problem out altogether more quickly than a weight shift!

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True, but you can always use the keyboard commands to set the aileron and/or rudder trim. FSX doesn't respect the 'bendable tab' system... ;)

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Thanks again for all the inputs above. I checked how I loaded the C172, it was the default- 170lb pilot and 170lb passenger and gas full, so not unbalanced. I did try without the passenger yep, that definately made the problem worse.Above, someone mentioned decreasing pfactor/torque slider in the realism setting. This did work though (gets rid of constant pull to right), and although this may be somewhat less realistic, IMO it is more enjoyable to fly, so this works good for me for C172, THANKS.Also, as advised, I do just lock to NAV1 or HDG bug with autopilot for long distances, but wanted a way to use twist rudder sometimes, with the ball in artificial plane working. Actually, like I mentioned, you can set autorudder on in settings and the twist on joystick still moves the rudder L/R, it is just not as sensitive and no ball movement.Also, FWIW, the P51 does have a rudder trim knob in the virtual cockpit, it is just to the left of the pilots seat. You have to really crank that up to get a level flight with P51. I don't know if it is true in actual flight, but as I gained altitude, I had to decrease amount of rudder trim. (since air is thinner, less torque effect?). Started off with about 25% positive rudder at 2000 feet Alt and decreased to 4% rudder by the time I was at 26,000 ft. It seemed to screw up somewhat during decent though, and required settings of -9% during landing, I think the SW got a little screwed up at this point, oh well.Also, that is funny that the rudder trim on actual C172 is set by bending a part outside the plane, LOL.William

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It isn't just a 172 that has these tabs that are bent on the ground-here are two shots of my Baron with these tabs circled-on the rudder and aileron.A plane is seldom perfectly in "rig" and though the Baron for instance has trim on all three axis's- you try to rig it so it will fly without the trim , set at neutral in cruise, by bending these tabs-a calibration so to speak.By the way-besides torque there 3 other forces (P-factor,Gyroscopic Precession , Asymmetric thrust) that can cause left turning tendencies in phases of flight, and unbalanced fuel tanks if you have single feeding from each wing can cause a wing to fly low.A very wise cfi I know went with a pilot on a small grass strip for some dual. Every time the pilot taxied to the end of a small grass field he had to shut down-get out and push the plane around to get it lined up as it was quite narrow. After watching him do this twice-the cfi asked the pilot why he was making his turns to the right? By making the next one to the left-utilizing the left turning tendency enabled the pilot to make a tighter turn-and not have to shut down and get out! http://www.mediafire.com/imgbnc.php/1b5baf...b9f427f694g.jpgMy blog:http://geofageofa.spaces.live.com/http://forums.avsim.net/user_files/187233.jpghttp://forums.avsim.net/user_files/187234.jpg

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>Also, FWIW, the P51 does have a rudder trim knob in the>virtual cockpit, it is just to the left of the pilots seat.>You have to really crank that up to get a level flight with>P51. I don't know if it is true in actual flight, but as I>gained altitude, I had to decrease amount of rudder trim.>(since air is thinner, less torque effect?). Started off with>about 25% positive rudder at 2000 feet Alt and decreased to 4%>rudder by the time I was at 26,000 ft. It seemed to screw up>somewhat during decent though, and required settings of -9%>during landing, I think the SW got a little screwed up at this>point, oh well.>While in a high power climb, you've got torque effects as well as P-factor and the prop's slipstream which is giving an additional left push to the vertical stabilizer & rudder. The P-51's vertical stab has a built in offset to help keep the plane flying straight at cruise speeds. And many planes have the engines offset at an angle on the mounts to do the same thing.The torque is so strong on a P-51; that it is easily possible to roll inverted, if throttling instantly to full power on a go-around while at landing speeds.L.Adamson

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With regards to the Realism sliders, a couple of CFI's I've talked to keep FSX all of the Realism sliders right on the Medium mark. They felt that FSX introduced too many contra-realistic (as opposed to unrealistic) behaviours at higher levels, making the sim more difficult than it needs to be.What I mean is that FSX by its own nature presents native obstacles to realistic flight. For instance, the monitor is too small to give you a proper view of the cockpit windows, and your controllers don't replicate the feel and action of real controllers. That, and FSX cockpits don't have the full functionality of real-world aircraft.There are very, very expensive solutions to these issues, but for the majority of sim pilots who fly their computer desks for an hour or two a couple times a week (including the afrorementioned CFI's who did not have all of the gaming gear that I do), the best compromise is to keep the sliders at medium. All that being said, there's personal taste involved, too. I don't consider it fun to wrestle with an untrimmable aircraft for more than a few minutes. If the autopilot was unavailable, I would land. If moving the sliders means I can concentrate on safe flight, then I move the sliders. Lastly, if you like helicopters, you're going to have to move the sliders to Medium, anyway, as that gives you the best rotory-wing performance in FSX.Jeff ShylukAssistant Managing EditorSenior Staff ReviewerAVSIM

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