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tunnelcat

Ocassional crazy 744 autopilot, wierd fix found.

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The other day I decided to set up a long transatlantic flight from Europe to the U.S. which took almost an hour to set up and taxi. Well, after takeoff, the autopilot on my Queen decided to do it's own thing. It refused to follow any VNAV, altitude or speed settings that were either set in the FMC or on the MCP for that matter. The aircraft just kept trying to climb as fast as possible, to the point of either stalling or over-throttling the engines (N1 max rpm warning). LNAV and even 'heading select' worked fine. I had to disconnect both the A/T and AP to stop the mayhem.This has happened in the past and I found a weird fix for the problem. I have to exit FS9, restart the sim and then load the PMDG 737NG. Then I again exit the sim, restart FS9 and load the PMDG 747. After all that runaround, the Queen behaves normally. The AP on the 737NG has never exhibited this bug.This problem occurs randomly without any changes to FS9. All I can think is that some other program on my computer is changing some file or setting. I even deleted the 'state.cfg' file in the PMDG 747 aircraft section and allowed it to be recreated with no results.Is there a better fix or do I just have to load the 737NG first before I fly the 747? My 737NG has been very useful in repairing my 747's autopilot. Weird.Kim

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Guest N405WN

Have you tried reselecting VNAV? That usually works for me.Marc Beck

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Kim,IMO by far the best method of initiating a PMDG flight is to use a saved flight wherever you wish with only the default Cessna loaded & powered down. In my experience you will never observe any abnormalities in this way.Steve B


Steve Bell

 

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I have tried both of these suggestions in the past with no results. The autopilot will ignore any VNAV or FMC settings and even ignore all altitude and speed settings that are displayed in the MCP. It's perfectly happy following LNAV or MCP selected headings but with altitude or speed commands, outer space seems to be the destination that it has in mind, at full throttle no less.The AP will pitch the aircraft down and retard the throttles when it stalls, but when it has recovered, the climb will resume again.The only two fixes I have discovered that work so far are to either start a flight with a PMDG 737 and then go to the 747 or run the repair utility on the installation CD, which I did once in the past before I stumbled upon the easier "load the 737 first" method.For now I will probably first run a short flight in the 747 to see if the AP is in a good mood and then I can go and plan a long flight with confidence. Unless I happen find the culprit in the future. Fortunately this problem doesn't seem to happen very often, just an occasional aggravation. Kim

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Guest Zane767

Hi, I brought the 747-400 a long time ago now and enjoyed flying it, after having problems with my computer and having to do numous reinstalls of windows I finally managed to re-activate and download the 747 again. But since I have had the same problem thats been reported above. I know for a fact it isnt a 'Pilot Error' because I've been flying 767 & 777s that have a simular autopilots and systems. Plus I have printed off all manuals, checklists and tutorals to resure myself that I am flying correctly. Also I don't fly alone I fly with a friend of mine and he's was sure of it being a fault with the aircraft its self, and what are the chances of two pilots making same mistakes. I don't have the 737 to do as above so could somebody help because it's real frustrating.Thanks for your time,Zane Andrew Saxton (PS It's happening all the time)Windows Vista Bus' 32bit,ATI Radeon X1300XT Pro1534MBAMD Sempron Processor 2800+ 1.60Ghz

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Update to my autopilot problem.This weekend, tried to fly the PMDG 747 after the computer had sat idle for a few days. AP problem returned again so this time I ran the repair function off of my install disk. Things worked OK, so I then installed the sound update from PMDG. That worked OK as well that day, so I assumed that things were fine.Well, after an overnight reboot, my Queen just went crazy. After I had set up the FMC and got everything started and running, a control check with the EICAS showed that the rudder was hard over to the left and the ailerons would flutter when you tried to do control inputs. The controls relaxed when I cycled the Flight Director off and on. Weird, no warm and fuzzies here I'm afraid. Well, I forged ahead with the flight, hoping for the best, LOL. Unfortunately, the AP was partially on strike again. Strangely it followed both LNAV or heading select functions like a puppy, but pitch was another matter. It would try to climb as steep as possible with full throttle. I also noticed that the Flight Director pitch line in the PFD was not being followed as well. The aircraft would then stall and pitch down, at which point the throttles would retard during a slight descent. Then after it had regained some speed it would pitch back up and firewall the throttles again.I finally had to bite the bullet and uninstall the sound update and the PMDG 747 completely from FS9, reboot and perform a reinstall from scratch, including all my liveries. After another reboot, I ran FS9 and set up my options that I had before. I did not install the sound update this time. I've read on this forum the problems many people have had with the sound update, so I don't think I will install it again. At this moment, the 747 seems to be performing normally after several hours of work. I'll give it a try after another overnight reboot and maybe celebrate then. I love this aircraft, but it is a pain to maintain. I'm glad that I own the disk version.Kim :-eek

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Guest Zane767

Hi There,Was begining to think that no one was interested in our problems. Yeah to confirm I have the excatly the same problem and it's VERY VERY annoying and a bit of a 'red face' on my behalf when I tryied flying it online tonight hehe. - Mind you it wasn't as bad as before after I did a repair to the installation.So what I'll do now is uninstall it completely and install only the 747 without the update. Not sure how to do that because the file I downloaded has it built into the installer, will look around for un-updated version on their site.Shame that the update has the problems (if it is that) because the new sounds are excellent.Kind Regards,Zane

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ZaneHold on! I went and tried out my Queen again today after an overnight reboot. It worked fine for the first flight with the first load of flight sim, but after that short flight, I went out of flight sim and back in and reloaded the 747 and the AP went crazy again, with a different route programmed in the FMC this time.This time I not only had trouble with the pitch control function, LNAV started behaving weird as well, the aircraft kept wanting to turn in the opposite direction from the NAV course line. It would follow heading select, however, when switched to that mode. I also noticed the throttles were behaving strangely too. They would stick at full N1, then at one point in the climb they suddenly released and dropped the speed down a bit. Then engines 3 and 4 suddenly began to retard while 1 and 2 stayed the same, all with the autothrottle still engaged. After this happened, then the aircraft began to follow the pitch commands in the Flight Director. Weird.This is getting old fast and I need to find out the problem soon. I'm beginning to wonder if my version of FSUPIC is corrupt. I don't own the full version, just the one that came with the Queen from PMDG, and it has never been overwritten by any other product. Maybe a new install of that would do the trick. You might want to try that first. All I know is that I don't have this problem with my PMDG 737 aircraft, which happens to use an older version of FSUPIC.Has anybody else had these problems?Kim

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Guest Zane767

Kim,I have emailed PMDG, they asked me to send them a screenshot of the panel (Probably to see if its a pilot error). I will let you know what they say and weather a solution is given and weather it works.If the problem continues to accour after many solutions given I will ask for refund. Because simply it doesnt work on my system.

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Guys,Post some screenshots here and lets see whats happening.Thanks,Armen


Boeing777_Banner_DevTeam.jpg

 

 

Armen L Cholakian
PMDG Sound Engineer

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Zane and Armen,It's getting murkier and murkier. I decided to get the latest update for FSUIPC, which is now version 3.7.4.0 from Pete Dowson's website. When I removed the old fsuipc.dll, version 3.5.0.0, file from the FS9 modules folder, I noticed something strange. The date that it was created was on 10/7/2006 (this date shows up when you hover your mouse pointer over the file name in Windows Explorer), but the date it was last modified was on 10/7/2005 (also listed on the far right in Explorer), well before I installed version 3.5 which came with the PMDG 747! How can that be? The only previous version I had was 3.4 that was installed with the PMDG 737. Is something weird here or am I mistaken about file dates.Anyway, I then put the new fsuipc.dll in my modules folder and removed the old .dll and associated .ini, .key and .log files. I haven't yet been able to try out the 747 yet today, my spouse is still using my fast computer today. If it works OK, great, but if the problem still exists with the AP, I will post a screenshot of the panel displays.I don't think that this is pilot error however. I've been flying this aircraft for quite some time and am very familiar with FMC and AP operation. Besides, the problem just recently cropped up after many months of flying with no problems, and it will occur even after loading the exact same route and parameters into the FMC and MCP on subsequent flights.Zane, don't give up on the PMDG 747, it's the best aircraft out there for FS9, I wouldn't trade it for any other. It used to work fine on my system and hopefully it will again, even if I have to reinstall FS9, eeeeeeek! I'll post my flight results as soon as possible.Kim

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Zane,Ooooooh, looks like a nasty climb rate, just like mine does. I can't remember the annunciations in my PFD and EICAS so I'll post my panel when I can get flying again, including the FMC VNAV page (my other computer is still being used). If you will notice, the Flight Director pitch cue is looking for a descent while the aircraft is climbing as fast as it can before it will invariably stall.Have you checked what version of FSUIPC you have? Just look in the modules tab from the pull down menu while you are in the sim. There is a version number there. If it's old, get the new version 3.7.4.0 from: www.schiratti.com/dowson.htmlKim

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Guest Zane767

Stupid isn't it - And it's getting to be the same old now. No reply from PMDG themselfs yet, will inform you when they do.You got Skype or MSN? Im zanesaxon on skype and zane.saxton(at)zandreweb.com on MSN

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Zane,Sorry, not on Skype or MSN.My computer that has FS9 on it is still tied up, so I will have to try my 747 tomorrow with the new version of FSUIPC installed. I'll let you know what happens as soon as possible. With computers, I don't have warm and fuzzies when trying to fix soft failures, but I'll cross my fingers.What I really need to do is either partition my hard drive and dedicate a section for FS9 or better yet, get a dedicated drive for it. It seems that adding or removing other programs screws up FS. One thing I ordered today is a copy of UltimateDefrag. The Microsoft version that comes with Windows is a piece of junk. It does more fragmenting than defragmenting and the computer is taking a long time to load FS9's textures, especially the Mega City titles.Kim

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