747-400X - Landing off-center rwy

[Guest jgcomp]

It seems that my 747-400X has adopted the idea of landing slightly to the left of runways, never at the center line as my LevelD 763 does. This applies to whatever airport or runway I choose. It is a bit annoying because until the last minute I dont know if I should disconnect autopilot to land manually. I know that some airports such as MMMX do not have a center ILS but this behaviour of my 747-400X applies also to airports such rwy32 CYOW, rwys CYUL, and others where CATII and CATIII are possible. Can PMDG or someone else put me on a possible resolution on this. Thanks in advance.Jean-Guy

[downscc 1,327]

Does this happen during a "coupled" ILS approach? (Using autoland)The coupled-ILS is the most accurate approach, using RNAV (GPS or RNP) requires that you take the controls at or above minimums and manually land. The most accurate these systems are required to be is approximately 0.1nm, which is 600 ft (this is worse case, they actually are better than that), that is not good enough to put you on a 150-200ft runway. This is very realistic.

[Guest jgcomp]

Many thanks, Dan, for your answer. Indeed, this is using Autoland because I use Autoland whenever I can or until the very last minute if I cannot. The reason being that the 3 computers of the FMS will get me very close very nicely, even in very reduced visibility. Obviously, from what I understand from your reply, I was wrong to believe that these 3 computers would get me right down on the center line. My consolation is that this is realistic. Would that mean that my LevelD 763 is not so realistic? It gets down on the center line in almost no visibility. I know they are a "competitor" but you do not sell a 767. ;-)Jean-Guy

[downscc 1,327]

In approach mode the autoland should put you right on the spot. If it is not, then something indeed is wrong. How about a screen shot just before landing, this is a good way to start figuring out what's wrong.

[Guest jgcomp]

>In approach mode the autoland should put you right on the>spot. If it is not, then something indeed is wrong. How about>a screen shot just before landing, this is a good way to start>figuring out what's wrong.>Below are screen shot showing flying the STAR, approach, final, land and rollout. Runway is 06L at CYYZ. This is an ILS CATII or CATIII.Hope this helps and thank you for your time.Jean-Guy

[G-CIVA 62]

Jean-Guy,Looks like the ILS Beam is not in the correct place for this airport.Each airport has the ability to have AFCAD file which holds positional & frequency information for various navaids, taxiways, gates...infact almost every functioning facet for a particular airfield (save autogen scenery etc).When FS9/X was written several issues such as these were either not spotted or rectified.A quick search of the AVSIM File Library will find many improved AFCAD files...easy to install & very useful.You will also be able to find an AFCAD editing programme by Lee Swordy...also very useful. You also need to examine the AoM & look closely at your upper EICAS page...those warnings are remedied by some simple drills, same goes for your SPDs & use of Flaps during the approach.Kind RegardsSteve Bell

[downscc 1,327]

I notice that the aircraft is dead center on the runway on the ND, this symbol is derived from the navdata wpNavAPT.txt file in the navdata. So, both the ILS and the navdata agree, which means the MSFS scenery has the runway location error. This is not uncommon in the MSFS world, and easy to check.Slew the aircraft the to runway threshold, then look into the navdata file and compare the coordinate there with MSFS coordinate(you'll have to convert ddmm.mm to dd.dddd format and it might be off by a few tenths of a second). This will confirm that the runway is depicted in the wrong location. The file format decode can be found at: http://ops.precisionmanuals.com/wiki/NAVDATA_Data_DictionaryYou haven't mentioned if this problem is unique to this location.Both Steve and my assumptions are that it is.

[Guest jgcomp]

Thanks to you both for your analysis. No, the problem is not unique to CYYZ (Toronto). As I mentioned in my first message, it applies also to many others such as CYUL and CYOW. What is peculiar is that flying to the same airports with the LevelD 763 results with a dead center landing. That being said, based on your comments, I begin to wonder whether the last downloaded AIRAC file 805 for PMDG might be the culprit. I'll temporarily switch back to the previous AIRAC file and report back.Jean-Guy

[downscc 1,327]

It won't hurt to try that... let us know.You can also try this... put a cessna in slew mode at the runway threshold and center the LOC needle.. is it in the center of the runway? If not, then the runway isn't lined up with the localizer (neither have anything to do with AIRAC LDS or PMDG). AIRAC data only reports where the localizer/runway is supposed to be, it doesn't position it. Once the 747 in in APP mode, it is following the MSFS localizer regardless of AIRAC data, which is only providing freq/crse and runway location used for presentation only. If the cessna's localizer is centered, then the problem becomes interesting. I'll give it a try on my rig at home this afternoon.

[Guest jgcomp]

Hi Dan,Indeed, you are correct on both counts. a) Reverting to a previous AIRAC did nothing.:( Runways are not lined up with localizers. I tried CYOW (rwy32), CYUL (rwy06L), CYYZ (rwy06L) and the cessna must be slewed a bit to the left for the LOC needle to centered each time.Now that this is established, I have no clues as to how this came upon. I used to have centered landings initially and I do not have any scenery add-ons. It would seem I might have to revert to an "uninstall and reinstall" of FSX. What a misery.......!@#$%^&.In any case, a thousand thanks again for your patience and the attention you paid to this issue. If you have other ideas, I am sure a listener.Jean-Guy

[Guest UlfB]

Hi,I've got exactly the same problem with autoland at ESMS. The FSX default ESMS localizer heading for rw 35 is 353 degrees, but the PMDG navdatabase says it's heading 351. Makes the aircraft land off center. Have the FS9 navdatabase been distributed with the FSX aircraft, that is with the old airport headings?Ulf BCore2Duo X6800 3.3GHz4GB RAM Corsair XMS2-8500C5BFG 8800GTX, Creative SB X-FiFSX Acc/SP2, Vista 32

[downscc 1,327]

You can modify an airport with Airport Design Editor, available free in the AVSIM library, it's like the old AFCAD stuff and very easy to use.I don't think a reinstall of FSX would fix it. It's just normal microslop.You can use ADE to nudge the localizer, or to put everthing in it's proper place depending how much much time you want to invest. And who knows, done correctly the rest of us will be downloading the results.

[Guest UlfB]

>You can modify an airport with Airport Design Editor,>available free in the AVSIM library, it's like the old AFCAD>stuff and very easy to use.>>I don't think a reinstall of FSX would fix it. It's just>normal microslop.Hi,Bad advice IMHO, since it seems that the upgrade of PMDG for FSX installed a navdatabase that seems to be very old. The ILS heading in the PMDG navdatabase is not the same as for the default FSX airport. Should I change the ILS headings for all the FSX default airports because a faulty navdatabase??? Much better would be if PMDG could distribute a correct navdatabase for FSX, which I think they will as soon as the cause is recognised by PMDG.Ulf BESMS

[downscc 1,327]

Ulf: A difference of 2-3 deg between navdata (not by PMDG but Navigraph) and the FSX localizer course is normal. The scenery data that is used in FSX pre-dates FS2004 in most cases, and magnetic variation changes in some locations almost 0.5/deg year.As long as the localizer has the same course as the runway, it doesn't matter what the course is... unlike VORs, the localizer only has one "beam" and either you are on it or not, the course setting is only to set the HSI display such that heading is up. This assumes that the localizer antenna is properly located in the airport scenery at the far end (opposite landing end). (Strictly, it is two beams and you on in the center when the two different amplitude modulations of each beam are summed to null - but that's the details).If the localizer has a different course as the runway, then the "beam" will probably not be over the center of the runway over the touchdown zone. (The localizer antenna is at the distant end, opposite the landing end). The symptoms for this would be the same as the original problem discussed above in this thread.A third possibility can be found at KJFK Ry 22R, where the localizer antenna is located on the side of the runway, and the course is different from the runway... and you can't use autoland to land on this one.

[Guest UlfB]

Hi Dan,I'm sorry but this doesn't make any sence to me.>Ulf: A difference of 2-3 deg between navdata (not by PMDG>but Navigraph) and the FSX localizer course is normal.No it wasn't normal with my 737 or 747 for FS9. 1 degree didn't make much diff, but between 2 and 3 does.I haven't installed any Navigraph add on, only the PMDG update.Have a look on these pictures and tell me what's right and wat's wrong. This is final, just before touch down, at ESMS rw35.http://forums.avsim.net/user_files/189058.jpghttp://forums.avsim.net/user_files/189059.jpgDo I need to uninstall the latest update and reinstall the PMDG to be able to perform autoland on default FSX airports?Ulf B