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Thunderbolt44

Localizer Course Changes Itself

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I have been flying the 900 version since the second day it was out with no real problems. I do have a couple of items I am puzzled over though. During my decent, I input the proper localizer freg and course setting. I update with Navigraph each month and use current ICOA approach plates. When transitioning to the localizer, as soon as I press either Nav or App, the course setting knob changes the localizer course anywhere from 1 to 3 degrees. There is no effect when you try to change the course knob back to the proper setting. This seems to be happening just about every approach now. Normally, this small change would only change the needle and the aircraft would still be centered on the center line. However, the ILS and heads up display instrumentation, shows the aircraft centered, but it is actually centered off the runway with 3 degrees being quite a bit. Breaking out at 100 ft requires somewhat of a dance step. Any comments are appreciated. Mike Nicholson

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I have been flying the 900 version since the second day it was out with no real problems. I do have a couple of items I am puzzled over though. During my decent, I input the proper localizer freg and course setting. I update with Navigraph each month and use current ICOA approach plates. When transitioning to the localizer, as soon as I press either Nav or App, the course setting knob changes the localizer course anywhere from 1 to 3 degrees. There is no effect when you try to change the course knob back to the proper setting. This seems to be happening just about every approach now. Normally, this small change would only change the needle and the aircraft would still be centered on the center line. However, the ILS and heads up display instrumentation, shows the aircraft centered, but it is actually centered off the runway with 3 degrees being quite a bit. Breaking out at 100 ft requires somewhat of a dance step. Any comments are appreciated. Mike Nicholson
This feature is by design. It's mentioned in the aircraft documentation, though I don't recall just where. The problem is that many localizers in FSX do not have the same course as their real-world counterparts... in many cases because the magnetic variation for specific airports has changed in the 6+ years since the FSX built-in runway database was finalized prior to the release of the sim.If you set the localizer course to a specific real world setting, based on current charts, and that course differs from the course hard-coded in the FSX AFCAD for the airport in question, the NGX will automatically change the course to what FSX expects.Unfortunately, this does not gaurantee that you'll end up properly aligned on the runway centerline, as there are a large number of ILS localizers in FSX which were never properly aligned in the first place.

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See intro manual...................page 55/56 SET FSX LOC CRS. If you turn that off your problem is solved.I always leave it off. ( PMDG do reccomend leaving it on !!)
could you explain a bit more. would it not be better to use the FSX value so that you land correctly? after all, you are actually landing at an FSX airport regardless of what the plate says. not sure I fully understand this.

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Hi, I checked this issue a while ago so I thought I'll just tell you what I think. If you auto set FSX course, there are times when it doesn't track exactly in the middle of the beam. Take for instance an example problem ILS where the AFCAD magnetic declination is messed up. The ILS is (in this case) fully aligned to the runway, so both runway and ILS loc have a heading of 140. Your "auto FSX course" will also set to 140. Everything seems normal. However you could be offset to the beam to the right or left. What happens is inside the AFCAD ILS magnetic dec difference causes the ILS to be assigned a hidden heading of eg 135. You can confirm this by using the FSX map viewer. Your parallel to runway, heading of 140, ILS is also parallel to runway, but click on the localiser, its heading is reported as '135'. So to actually fly ILS exactly, your course should have been 135, instead of 140 as assigned by "Auto set", while your heading is still maintained at 140. So possible solutions at this time, is fix the airport such that the ILS course accurately reflects 140 like everything else,2) do not use "AUTO SET" but adjust course to the "wrong" value (135) in order to fly straight on the right (140) heading.3) Or 737 NGX is patched to extract the hidden heading of 135 for autoset, instead of 140, which I am not sure is possible for FSX or not. RegardsMarcus Jian

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These Forums are just great! I write my question before going to bed, and here I sit at 0600 in my robe drinking my coffee reading the answers. I had copied the Introduction Manual and yellow highlighted a number of items. Somehow, I had just skipped over this. Will try the above mentioned suggestions later in the day. All-in-all, I really respect FSX. I view it as the flight simulator Operating System and use add-ons for just about everything else. I guess it's a wonder we have as few of these problems because of it as we do. Appreciate the advice. Mike Nicholson

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The NGX doesn't auto set the FSX course, it auto sets the navdata course. It has no way of knowing what course the actual ILS is using. That's why you're better off leaving the option mentioned above to off. Before you start a flight, just use the map feature in FSX and see what are the actual ILS courses at you destination, and use those.

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If your FSX Airport Runway Information does not agree with the latest AIRAC then it is time to go looking for a newer AFCAD. With this in mind you have 2 choices. You can go buy a payware airport which would have a newer AFCAD than FSX Default or you can look for a freeware AFCAD on AVSIM of which there are many! One popular author is Ray Smith. He has put out a ton of AFCADs to fix various errors in FSX airport AFCADs.He adds more than just fixes to the Runway info. In many of his AFCADs new Terminals, Gates, Taxiways, are added as well as Fire Stations and Cargo Areas. It is definately worth your time to at least get an updated AFCAD for all the airports you fly into regularly. Having problems with FSX Default Airports when using the latest Charts and AIRACs is to be expected considering the information from most of the airports dates back to 2006. Not only are they outdated but there are also many airports that have errors. Look at the examples below. The majority of these airports were updated by Ray Smith. Look at the bottom of this post for important installation information. Default FSX Airport Updates EDDK - Cologne EGNX - East Midlands KATL - Atlanta KBWI - Baltimore KCLT - Charlotte KCVG - Cincinnati KDEN - Denver KEWR - Newark KGSP - Greenville KIAD - Washington DC KMIA - Miami KOAK - Oakland KONT - Ontario KPHL - Philadelphia KPHX - Phoenix KSEA - Seattle KSLC - Salt Lake City LIRF - Rome NFFN - Fiji NSTU - Pago Pago NZAA - Auckland OMDB - Dubai PANC - Anchorage RJAA - Tokyo RJTT - Tokyo RPLL - Manila SBKP - Campinas WIII - Jakarta WMKK - Malaysia YPPH - Perth YSSY - Sydney One thing to keep in mind here. Usually there is a warning about only having one AFCAD in use at a time in the Addon Scenery/Scenery Folder. For Each AFCAD update or Freeware Scenery I put them in the Addon Folder and give each Airport it's own Folder, to get around the above issue. This way I never have to swap AFCADs when I fly to a different Airport. Example for YSSY. I create a Folder called YSSY and then go into YSSY Folder and make another Folder called Scenery. Drop the updated AFCAD in the Scenery folder. Then you start up FSX and add the Folder YSSY to your scenery Library. With some sceneries though there will be an additional file or two to add elsewhere such as files that go in the Scenery/Global/Scenery or Scenery/World/Scenery folders. So it is important to review the readme.txt files that come with each AFCAD Update that will tell you how to install it correctly. Very easy to do if you follow the instructions and put the files in the proper locations. With Payware Sceneries you do not have to worry about this step most times. The installer usually sets everything up for you automatically.

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The NGX doesn't auto set the FSX course, it auto sets the navdata course. It has no way of knowing what course the actual ILS is using. That's why you're better off leaving the option mentioned above to off. Before you start a flight, just use the map feature in FSX and see what are the actual ILS courses at you destination, and use those.
According to the explanation in the Intro manual, the NGX does indeed read the hard-coded FSX localizer course, and auto-sets the course in the MCP to match. This won't always happen - if the pilot sets the MCP course using the information from a real-world approach chart, and it happens to match the FSX course, there will be no auto shift. But, if the two courses differ, the NGX will default to the hard-coded FSX course at some point in the approach phase.

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Remember, changing the course setting has no effect on the localizer deviation shown on the PFD/ND, only for VOR.
The NGX doesn't auto set the FSX course, it auto sets the navdata course. It has no way of knowing what course the actual ILS is using. That's why you're better off leaving the option mentioned above to off. Before you start a flight, just use the map feature in FSX and see what are the actual ILS courses at you destination, and use those.
Both of these are completely incorrect. It does affect the localizer deviation and we do read the actual ILS course out of the BGL.

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Both of these are completely incorrect. It does affect the localizer deviation and we do read the actual ILS course out of the BGL.
So what should the setting be as far as turning the option for FSX Crs in the CDU on or off?

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I agree with you ! That is why I turn it off. Otherwise it will use the Navigraph data which is proably correct but try telling FSX that !!!
The reason I asked for further explanation is that your reasoning was contrary to my understanding. This option should be ON as it only makes sense to use the FSX number NOT the nav data number. Unless of course there is further discovery, follow the recommendation in the PMDG intro.

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So what should the setting be as far as turning the option for FSX Crs in the CDU on or off?
YMMV, but I've had good luck leaving this option turned "on". I always try to use real-world charts in my simulated flying, but I learned long ago that because of the differences between real-world localizer courses vs. those in FSX, that using the real-world data would often result in being misaligned with the runway. I began to use the airport lookup function in Flight Sim Commander to determine what the FSX course was for specific runways, and would use that value for setting the MCP course. Only problem with doing that (when using add-ons other than the NGX) is that it will often lead to an FMS nuisance error message complaining that the selected localizer course is wrong - since most addons (including earlier PMDG releases) depend only on the current FMS database to determine what a given runway's localizer course should be, regardless of what is actually hard-coded in the FSX AFCADS. Using the auto-set option in NGX eliminates the need to do that. (Lookup the actual FSX course in advance). But, it won't help if the hard-coded FSX course itself is misaligned - which is the case at quite a few airports. I did find that installing the updated magnetic variation files has helped correct quite a few of these. I'm now following Paul Deemer's advice and starting to install updated AFCADS to fix many of the the default FSX airports once and for all.

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According to the explanation in the Intro manual, the NGX does indeed read the hard-coded FSX localizer course, and auto-sets the course in the MCP to match.
Both of these are completely incorrect. It does affect the localizer deviation and we do read the actual ILS course out of the BGL.
I'm sorry... apparently I got my facts wrong.... Oops..blush.png

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Both of these are completely incorrect. It does affect the localizer deviation and we do read the actual ILS course out of the BGL.
Er, what?!A localizer is fixed on a given heading. Changing the course set on the HSI of any other aircraft I've ever come across has never had an effect on localizer deviation. Is the 737 different?Remember, I'm talking about deviation, not the heading of the pointer on the ND compass rose.

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Er, what?! A localizer is fixed on a given heading. Changing the course set on the HSI of any other aircraft I've ever come across has never had an effect on localizer deviation. Is the 737 different? Remember, I'm talking about deviation, not the heading of the pointer on the ND compass rose.
You are correct about the logic behind normal ILS pointers. The ILS doesn't know about your selection in CRS, ILS receiver in AC only gets two localizer beams and compares them and gives you the deviation, at least on normal AC only reason why you put LOC CRS into HSI or whatever is that it is easier to fly when your needles are straight. I find it a bit weird that 737 would act differently, where does it get it's deviation data if not from localizer beams...?

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so thus with this bug if you want to callit, what would befo now the current solution. For example I am approaching JFK from the south and this happens in all directions, and I get runway 13l, I don't even come close,its like as I am landing on runaway 4l. do we stop running it in the cdu or not don't even put t in once you getyour landing assignmnet.

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Assuming you disabled auto set course.One of the possible solutions (if you dont want to pause the sim to check the FSX map), is to set your best guess into the course settings, typically your current heading once your quite parallel to runway heading. Then you see if your too much left or right of the needles, which means your not tracking the ILS correctly. If your too left of the runway, increase course until the needle is centred. And the other way for right. At least this works for me 'on the go' for now. Adjust both pilot and co pilot if your doing the CAT3 autoland. Of course you have to confirm that your not landing at an offset ILS, but a runway parallel one that isnt working so correctly.Offset ILS- your needles are centered and you're flying at an awkward angle.Problem ILS- you're flying at an awkward angle, loc needle never completely centred, no matter how long you wait. Depending on how badly screwed the FSX data is, you can have ILS 'errors' that you barely notice, to ones where you'll land on the grass. Marcus Jian

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Wow, I never dreamed I would get so many comments. After reading through them this morning, I just followed JasonG's advise and turned the FSX LOC Crse to OFF. Right on the center line with no problems. Thanks guys, Mike Nicholson

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