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Vineguy

CDI needle on wrong side for ILS landings.

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I have been flying Flight Simulator since 1984  (yes, I am old) and FSX since it came out in 2006. My problem is that when I am vectored to a ILS approach to KSFO the CDI needle is on the wrong side for the approach. I have tried updating the navaid base with no difference. It happens on all runways at KSFO that have an ILS approach. All other airports work fine. I am using MTX 6.0 and have made the blg. for KSFO passive and that didn't work either.

I recently updated my OS from Windows 7 to Windows 10. Other than that I don't have any add-on aircraft.

Appreciate any ideas.

Bob G.

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Bob,

 

Could you elaborate on "... the wrong side for the approach"?  I'm assuming you're not flying a back course, you've tuned in the correct ILS frequency, and that the needle isn't on the same side as the runway.  Correct?

 

Dave

(started in 1983 with FS for the Commodore 64, yes, old too)

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Personally, I've never seen the BC button work.  It should flip the localizer indicator to the other side, shouldn't it?  Or am I missing something.

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Personally, I've never seen the BC button work.  It should flip the localizer indicator to the other side, shouldn't it?  Or am I missing something.

 

BC button is an autopilot function.  On a back course approach, flipping a deviation indicator to the other side is only possible (in a relative sense) with an HSI, where the front inbound course should be set to "negate" the reverse sensing (this will be opposite your true inbound course on approach).  Conventional CDI equipment can't negate it, and will always be flown reverse sensed (with the OBS set to the back inbound course), and thus the BC button is needed to get the autopilot to properly steer "away" from the deviation indication to intercept the loc.

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BC button is an autopilot function. On a back course approach, flipping a deviation indicator to the other side is only possible (in a relative sense) with an HSI, where the front inbound course should be set to "negate" the reverse sensing (this will be opposite your true inbound course on approach). Conventional CDI equipment can't negate it, and will always be flown reverse sensed (with the OBS set to the back inbound course), and thus the BC button is needed to get the autopilot to properly steer "away" from the deviation indication to intercept the loc.

 

Now I feel dumb.  I don't know why I always expected the HSI to show what the autopilot was thinking.  Thanks Damian.

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1.  Upload it to a site like imgur.com

2.  Right click on the image to "View Image" after it's uploaded.

3.  Copy the link

4.  Click the little picture icon on the toolbar and paste the link.

 

TT8h7oC.jpg

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Okay. I know how to do a ILS landing. The question is why does it only happen at KSFO? It had been working fine in the past. Could a Windows update cause such a problem?

Is there something messed up in the panel config?

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Okay. I know how to do a ILS landing. The question is why does it only happen at KSFO? It had been working fine in the past. Could a Windows update cause such a problem?

Is there something messed up in the panel config?

Is it actually keeping you from doing the ILS landing on Runway 19L at KSFO?  Seeing your screenshot over at the

other site, I assume you are flying a TDS 737 with the older 737-400 2D cockpit?

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Forget the screenshot as I said. It was not taken during the actual approach but much later when the App. didn't work/.

The aircraft is the default B737-800 with a panel I have been using for years. You can find it by searching the library for a file named, greg737.zip.

The question is simply, why does it just happen at KSFO?

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I, too, have "flown" Flight Simulator since before MS stole, I mean, acquired it.  Visuals and content have certainly changed since those days.

 

To your question, if you had no problem when using Windows 7 and now have a problem using Windows 10 it sounds as though that is your problem.  I have heard of others with the CDI needle on the wrong side.

 

Another thing, with this being your only add-on aircraft, you cannot tell if you have this problem with other add-on aircraft, in other words it is possible Windows 10 is playing havoc with the software you have.

 

I thought about shooting an approach at that airport with a few different add-on aircraft, however, I am still using Windows 7 and the results would most likely prove invalid compared to Windows 10.

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@Dan. This  would happen when using W7 also, but not every time as the problem I am having with KSFO. I am not using a add-on aircraft. Default B737-800 or any default FSX aircraft, this will happen.

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