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ArjenVdv

LNAV problem, please help PMDG, I already tried everything you said

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Hello, You probably know of this problem PMDG. LNAV is not maintaining the magenta line at cruising altitude after a change in wind direction or speed. I know this has been discussed quite a lot, several times by me, but I can't solve it, and I'm not getting any response from you PMDG, except from Dr. Vaos who tried to help me really nicely, but unfortunately that didn't work.I already tried everything you and other people adviced me, but nothing worked, this is what I tried: - Disable turbulence and thermal effects on aircraft- FSUIPC weather smoothing on- Supression of winds, gusts, variance and turbulence set to on in FSUIPC- WeatherReadFactor=0 in FSUIPC.ini file- Fixing FSX's registry using the tool from Flight1.com.It's really hard to explain the problem, but I will try.Most of the time I'm flying from SID to STAR. That means there is a very long leg of about 1000 nm. Today I was flying from EHRD REFSO1B to BIKF (ILS 29), so that means I was flying directly from REFSO to CI29. Real world weather of ASE was on, when I was at cruising altitude LNAV maintained the magenta line quite well, there was a small deviation though, of about 0.02 nm, but that's no big deal. After a while at cruising altitude, there was a weather update, and LNAV wasn't doing anything at all to correct it. The aircraft got directed more and more off the magenta line, at about 3 degrees off the heading of the leg. So after a while the deviation was more then 20 nm! So I used HDG SEL (which worked OK) to get back on the magenta line, when I was back, I engaged LNAV again. But then, it was turning right again away from the magenta line! Why is it doing this? It just doesn't make sense, why can't it just maintain the magenta line... I tried EVERYTHING other people and you (PMDG) adviced me, but NOTHING works. Also some interesting information may be this: when I have this problem, LNAV is always turning right relative to the magenta line, and I never had this problem when I was going to the left. It's not doing S-turns though, it's just heading away very slowly from the magenta line. I have this at pretty much every flight, and it's annoying me so much! It just must be a bug, because I've never had this in the MD-11 and 747, even with turbulence on! Please fix this PMDG, and why is noone else experiencing this? I don't understand it. It anyone has any suggestions, that would be really nice. I also submitted a ticket, but never got any response, I payed $70,- , and I would like support for that! Thanks a lot in advance, Arjen Vandervelde

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It might have to do with projection. The FMC draws a straight line between the waypoints, but the world is a sphere. Google "great circle projection" for more info. Whats the ANP at that time? The FMC should give you info about how far you have deviated from the planned path. As for flying 1000nm legs, I think that would be illegal almost everywhere. You should try to use real life routes with more sane distances between the legs on your flightplan.

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I didn't see your original post but that route would require about 32 tons of fuel so a couple of thousand miles with no fixes on route, I don't think LNAV is used to that kind of " guesswork".Try a short route or file a proper flight plan and see if it does the same thing.Have you reselected the current on route fix into the FMC? Press LSK 1 twice and EXEC? This will direct you from your present position to the fix, with changing weather and legs of over a thousand miles you won't get a well behaved prediction.If you have tried all this already then disregard, as I said I didn't read your first post.Dan.Beat me to it!Dan. :)

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It might have to do with projection. The FMC draws a straight line between the waypoints, but the world is a sphere. Google "great circle projection" for more info. Whats the ANP at that time? The FMC should give you info about how far you have deviated from the planned path. As for flying 1000nm legs, I think that would be illegal almost everywhere. You should try to use real life routes with more sane distances between the legs on your flightplan.
On the ND I'm now 15 nm to the right of the magenta line, but the ANP is 0.06, RNP is 2.00. I don't know what ANP and RNP means, could you explain me?And about the real life routes, could you recommend me something to create those routes? I don't like FSBuild to be honest. Same for flightaware.com, because I doesn't have most of the flightplans I need.Arjen Vandervelde

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Arjen, you can start with vroute, it has all you need in it's freeware version. BTW, I'm not surprised that you have such problems flying a 1000nm legs ;)

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RNP = required navigational performance. It basically describes how far away from your planned flight path you are allowed to fly. ANP = actual navigational performance. It means how far from your planned flight path that your plane currently is. If your ANP is 0.06 then that means that you are 0.06nm away from your planned path, at least thats what the plane thinks. You can get valid flight routes from sites like simroutes.com and vatroute.net.

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I just got this route from vroute (my database is out of date though). It is also from EHAM not EHRD but thats not the point. BERGI UL602 SUPUR UP1 ROLUM UP13 ASKAM UL7 SUM UM125 GONUT G11 MY G3 SKARD Try that route and see if it is any better..... Dan.

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It might have to do with projection. The FMC draws a straight line between the waypoints, but the world is a sphere.
Sounds like a reasonable explanation, maybe that aspect of the FMC got simplified slightly in the NGX. Try this route: EHRD TULIP UP1 ROLUM UP13 ASKAM UL7 FORTY UP60 BAMRA UP61 DEVBI UP61 RATSU VM BIKF

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It's really hard to explain the problem, but I will try.Most of the time I'm flying from SID to STAR. That means there is a very long leg of about 1000 nm. Today I was flying from EHRD REFSO1B to BIKF (ILS 29), so that means I was flying directly from REFSO to CI29.
If your ever planning on flying online or wanting to learn how things are done the proper way you will need to learn how to bill a proper flight plan. Nobody flys from Point A to Point B. For example flying from EHRD to BIKF would look something like this.REFS1B REFSO UL980 WESUL UM14 STOAT UL613 FINDO UM87 GONUT G11 MY G3 METIL KEFI did't include a STAR becasue none were listed for BIKF. I know people hate buying a 70.00 plane only to find out they have to spend more money, but Flight Simulator is an expensive Hobby. Some will spend more and others less, nothing wrong with that. However there are 2 essential things you will want to have to really enjoy FSX.1) A Good Flight Planner that can import your flight plans directly into the FMC. FSBUILD or FlightSim Commander for example. 2) A good weather generation program such as Activesky.I think the reason your not following the magneta line is because there is a 1000 nm gap between your start point and ending points. Your just going to have to learn how to program a flight plan, thats just something that all pilots need to know and there is no getting around it.

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... 1) A Good Flight Planner that can import your flight plans directly into the FMC. FSBUILD or FlightSim Commander for example....
I believe that its possible to use freeware alternatives like simroutes, vroute or http://www.virtual-dispatch.net/ as alternatives to the paywares you listed for generating PMDG .rte files. OP could of course also learn how to program the route manually into the FMC, its not very difficult at all

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If your ever planning on flying online or wanting to learn how things are done the proper way you will need to learn how to bill a proper flight plan. Nobody flys from Point A to Point B. For example flying from EHRD to BIKF would look something like this. REFS1B REFSO UL980 WESUL UM14 STOAT UL613 FINDO UM87 GONUT G11 MY G3 METIL KEF I did't include a STAR becasue none were listed for BIKF. I know people hate buying a 70.00 plane only to find out they have to spend more money, but Flight Simulator is an expensive Hobby. Some will spend more and others less, nothing wrong with that. However there are 2 essential things you will want to have to really enjoy FSX. 1) A Good Flight Planner that can import your flight plans directly into the FMC. FSBUILD or FlightSim Commander for example. 2) A good weather generation program such as Activesky. I think the reason your not following the magneta line is because there is a 1000 nm gap between your start point and ending points. Your just going to have to learn how to program a flight plan, thats just something that all pilots need to know and there is no getting around it.
I know how to construct proper flightplans. Normally I use the default FS Flightplanner for this, then I print the NavLog and manually enter the airways into the FMC. But i'm experiencing quite a lot of problems with it. Quite a lot of times, the FMC says "Invalid Entry" to some airways, or "Not in database" to some waypoints. That flightplan you just created look really nice, what program did you use do contruct that flightplan?Thanks in advance,Arjen Vandervelde

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I know how to construct proper flightplans. Normally I use the default FS Flightplanner for this, then I print the NavLog and manually enter the airways into the FMC. But i'm experiencing quite a lot of problems with it. Quite a lot of times, the FMC says "Invalid Entry" to some airways, or "Not in database" to some waypoints.
The reason your probably getting those errors is cause your AIRACS is outdated. If your using the one that came with the 737-NGX that is way out dated. Need to keep your AIRACS files up to date for your planes and for your flight plan builders. To do that you need to go to navigraph and purchase some credits and get the monthly update. For about 12-13 dollars you can get 100 credits which is good for 5 months worth of AIRACs at 20 credits per month. AIRACs include the very latest SIDS and STARS and Procedures. This is actually another must have if you want to get around the world. You can check it out here. http://www.navdata.at/ Once you get some credits wait about 5 or 6 days until the september AIRACS comes out cause August is almost over. Then when you do go get it you download the AIRACS for PMDG which will update the PMDG FMCs for all your PMDG planes. If you have any other planes such as the Level-D you can download the update for that to. Navigraph covers just about every popular plane and flight planner out there.
That flightplan you just created look really nice, what program did you use do contruct that flightplan?
I used FlightSim Commander for that but its a pretty complex program. For a beginner such as yourself I would recommend something easier like FSbuild which is what I started out with.

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The reason your probably getting those errors is cause your AIRACS is outdated. If your using the one that came with the 737-NGX that is way out dated.
Actually, the NavDB that came with the NGX is the most current one - cycle 11-08, which expires in 4 days on Aug 25th, at which time cycle 11-09 becomes current.It's the default flight planner built into FSX which is way out of date, and if Arjen is using that to build a flight plan, it will probably reference many airways and fixes which no longer exist, thus the error messages when he tries to enter them in the FMS.Another free flightplan generator is Routefinder at http://rfinder.asalink.net/free/ It usually does a pretty good job, though once in awhile it will generate a plan that is far from the most optimal routing.

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Oh the one released with the NGX was the latest? I never thought to check that when I installed it. In the past the AIRACS included with the 747-400 and MD-11 were very old and outdated so I just assumed the same with the NGX. And your right if he is using FSX for flight planning thats why his FMC don't like some of his entries.

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Oh the one released with the NGX was the latest? I never thought to check that when I installed it. In the past the AIRACS included with the 747-400 and MD-11 were very old and outdated so I just assumed the same with the NGX. And your right if he is using FSX for flight planning thats why his FMC don't like some of his entries.
Yes, apparently PMDG had an agreement with Navigraph, allowing them to include the database which was current at the time of initial release. I'm sure that was a one-time thing, so those who initially buy in NGX in coming weeks or months will still get the August 2011 database, not the one (then) current.The FSX default flight planner is now so far out of sync with present day nav data that it's bound to cause issues when used with the NGX, or any other add-on which utilizes the up-to-date Navigraph databases.

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