Hi all, Well, it seems that a couple of days ago, I started to notice that my aircraft are tracking slightly to the left of the course line. For example, I flew the PSS A320 the other night from ORD-TPA. Winds were out of the west, and the aircraft was tracking left of the course line the mcdu plotted. I thought then that it was because of the winds. Well tonight, I am flying out of Mexico to PHX in the PMDG 737-700, and the winds are once again from the west, but the aircraft is still tracking left of the course line. Before I reach the next waypoint, the aircraft will always turn back towards the waypoint again slightly, but will continue to be left of course. And the final bit is when I was on the ILS for 25L at PHX, and my aircraft is tracking the ILS but it's about a mile off to the left of the runway. Heck, even the steering bar is showing me way left! Is there any way possible that something in FS got messed up, and if so, what file do I need to get fixed? I thought I had heard of something like this happening occasionally to others in the past, but I don't remember the fix for it. If anyone can shed any light on this, I'd certainly appreciate it. Thanks in advance.ChuckC-130H Flight EngineerDyess AFB, TXAthlon XP 2800+ | ASUS A7N8X-E Deluxe | Antec TruePower 480 PS | 1.0 gig DDR PC2700 | WD 120 gig HD | WD 80 gig HD | Twin WD 160 gig SATA HDDs | SB Audigy 2 | ATI Radeon 9800Pro 128 | CH Products USB Yoke | CH Products USB Pedals | Nostromo n52 | Windows XP Pro SP2http://www.precisionmanuals.com/images/forum/ng_driver.jpg

Hi there. Just a thought. Have you the gyro drift set to 'on'-- in which case you would need to click 'd' every so often to keep the plane on track. Otherwise there is a drift to the left.Andy.

Andy, Thanks for replying, but I don't have gyro drift checked 'on'.ChuckC-130H Flight EngineerDyess AFB, TXAthlon XP 2800+ | ASUS A7N8X-E Deluxe | Antec TruePower 480 PS | 1.0 gig DDR PC2700 | WD 120 gig HD | WD 80 gig HD | Twin WD 160 gig SATA HDDs | SB Audigy 2 | ATI Radeon 9800Pro 128 | CH Products USB Yoke | CH Products USB Pedals | Nostromo n52 | Windows XP Pro SP2http://www.precisionmanuals.com/images/forum/ng_driver.jpg

Chuck depending on how strong the winds are aloft, it is very realistic for an aircraft's autopilot to compensate by tracking slightly off course. In the real world that's part of flight planning. You may have a heading from one visual check point to another at say 350 degrees. In actuality you may have to fly 340 degrees to compensate for a slight head wind. Even in landings you may have a crosswind you might have to factor for causing you to kick in a little rudder to straighten out right before your wheels touch the ground...Chuck flying airplanes is not like driving a car down the road. Flight Simulator is not quite there yet (although we're making extraordinary progress) but it's like a whole other world dealing with the forces of weather aloft. If you get the time take a ground school course at you're local airport to get a better understanding of all this.... :-)

Hi Chuck,I'll assume that you are using Autopilot Nav1 Hold to follow your flight path. If so, is it possible that either the rudder or aileron trim is misadjusted? Here's what I would try:1. disable all winds,2. use Autopilot Heading Hold to fly sraight,3. examine the turn indicator (the ball should be centered),4. disengage Heading Hold and do not touch the yoke or pedals.If the turn indicator ball is not centered in Step 3 or if the plane turns left or right in Step 4, then it is likely that either rudder trim or aileron trim is causing it. The autopilot will use rudder and/or ailerons compensate for the out of trim condition but it can't correct the trim problems. You can fix it manually using the horizon and the turn ball as indicators. R-

Dillon, Thanks for the information, but I am a student pilot, and as my signature suggests, I am a real-world C130 Flight Engineer, so I have a working knowledge of aviation and aviation weather. The fact of the matter is that while on the ILS last night, the winds were right down the runway, and yet my aircraft was over a mile off of course, to the LEFT. I point the 'left' out, because everything I encountered seemed to have the aircraft left of course. If the winds were the problem, why would the aircraft be left of course while heading south, north, east, then west, all while the winds were predominately out of the west? Judging by your banner, you've flown the PMDG 737NG's, so you know that these aircraft track on an ILS very, very well, with both autopilots engaged, even in a stiff crosswind. What I experienced was not too strong of a wind, but most definitely, a discrepancy in the what the aircraft perceived as being 'on course'. The aircraft was off course, it seemed, magnetically. After my flight, I went and cleared all weather and tried again. I still got the same left of course result. So I started hunting down suspect files. I looked for some files in my FS installation and found one in the primary scenery folder under BASE. The file was called magdec.bgl and I reinstalled that file with the original file off of CD number 3. I will be testing this out this evening, and hopefully, I will know if my detective work paid off. I will post what I have found as soon as I get the chance. Thanks again.ChuckC-130H Flight EngineerDyess AFB, TXAthlon XP 2800+ | ASUS A7N8X-E Deluxe | Antec TruePower 480 PS | 1.0 gig DDR PC2700 | WD 120 gig HD | WD 80 gig HD | Twin WD 160 gig SATA HDDs | SB Audigy 2 | ATI Radeon 9800Pro 128 | CH Products USB Yoke | CH Products USB Pedals | Nostromo n52 | Windows XP Pro SP2http://www.precisionmanuals.com/images/forum/ng_driver.jpg

I have an occasional problem with gyro drift, even though I have the option off all the time. Try hitting "d" to see if that helps. With the option off I still get drift once in a while. I have no idea why. I had asked about it a few weeks ago, but nobody had any information on it. Could be the same problem? Just a guess.

HiCheck your magnetic heading with the runway heading at any apt.Your heading may be corrupted by a bad scenery file.Arnold

It would not hurt just as a check to run FS in overhead view while locked to AFCAD to insure the AFCAD files and airport scenery line up. I'd also check the NAVAID properties to insure mag deviation compliance if you have the plates handy.Perhaps some major scenery or afcad install for many locations messed things up.One concern regarding alignment is if FS2002 scenery was used for FS9 (or vice-versa). The alignments betweenthe two sims differed slightly according to a thread some time ago. While this does not address the rounded legs enroute it might be a concern at airports.Another issue is addressed by your type of AP coupling. If you are using RNAV/GPS it could differ slightly from VOR navigation over long legs.As always, try a default aircraft before an add-on to rule out add-on issues such as navigation database conflicts depending on their NAV instruments design.

ronzie,Nail on the head sir!! It looks like I had an AFCAD that was causing the problem. It has been removed, and everything is just peachy now. Thanks to everyone that posted, it was much appreciated.ChuckC-130H Flight EngineerDyess AFB, TXAthlon XP 2800+ | ASUS A7N8X-E Deluxe | Antec TruePower 480 PS | 1.0 gig DDR PC2700 | WD 120 gig HD | WD 80 gig HD | Twin WD 160 gig SATA HDDs | SB Audigy 2 | ATI Radeon 9800Pro 128 | CH Products USB Yoke | CH Products USB Pedals | Nostromo n52 | Windows XP Pro SP2http://www.precisionmanuals.com/images/forum/ng_driver.jpg

There have been incidents where this has happened before. If you could post the specific AFCAD file title it would alert the author and users of this problem. I see no problem here as long as you have confirmed that this specific file (or installation routine if used) caused the problem.It could solve similar problems for other users.(Consider this a bug report, not a criticism.)