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Guest stubbornswiss

Reciprocal Runways - Same ILS Freq: HELP!!

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Greetings!Approaching KBWI, I was cleared for ILS 15R. I set up FMC for the approach, but never intercepted the localiser.I then did some investigating and dicovered some strange things.I'm hoping someone can help.First of all, I discovered that although the FMC indicated the correct ILS freq./course for Rwy 15R, the PFD was indicating the wrong ILS ident./course. (see image). With some more investigating, I discovered that the ident./course that was displayed on the PFD was actually for Rwy 33L, the reciprocal runway. On looking into my Navigraph charts and also the AirNav site, I see that both runways 15R and 33L have the same ILS freq.Is this possible? If so, how would one ensure that the receiver is tuned to the correct runway. As can be seen in the image, even when I was shooting the approach using VNAV/LNAV, the PFD was still displaying IRUX 336deg (for rwy 33L), rather than IFND 155deg (for rwy 15R).FYI, entering the ILS freq./course into the FMC manually produced the same results.As is usual, thanks for the assist.

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this is a first for me. ive never seen an airport where 2 reciprocal runways would share the same ILS frequency. usually they would have different frequencies or 1 of the runways would be visual. you can edit the frequency and or the course heading via the TXT AIRAC files located in C/Program Files/Microsoft Games/FS9 or FSX/PMDG/SIDSTARS folder.personally if i ran ( or flew ) into a problem like this, i would disconnet the autopilot and land the Queen manually.or when you program the approach, at the T/D use the OM as your next waypoint fly under HDG SEL and vector yourself to final. that would probably not be recommended by R/W pilots but it might change the course heading on the EADI to the correct one.

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Real world, it's quite normal to have the same frequency for both runways, as only the localizer and glideslope for the active runway (15R in your case) are switched on.In flight sim, the localizer and glideslope for both runways are constantly switched on, although the aircraft should pick up the other runways ILS once you get to that end of the airport.The only time I've seen this problem is if I've installed an add-on scenery or non-default AFCAD file

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As a matter of fact, I did have an add-on for KBWI. However, I had already removed it from the "Addon Scenery > scenery" folder before I discovered this anomaly.Could this still be the culprit? If so, any ideas?Thank you gentlemen!

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go to NAVDATA.com and download the KBWI PMDG txt file. place it in the navdata folder in the PMDG flight sim directory. you should be fine after that.

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In FS default scenery localizer backcourses are always active. Where the same frequency is used at both ends of a runway there is a conflict and you will pick up unless within two degrees of center-line the wrong localizer as you discovered in looking at the ident.To fix this, download AFCAD v221 for FS9 from the utilities library here, and using the navaid dropdown open up each of the opposing localizers' properties. Turn off the backcourse of each and save the file to a folder such as H:AFCAD2Sscenery. Add this folder to your scenery library leaving it at high priority position 1. Start FS to reindex the scenery, then close it.If you have any applications that extract data from your scenery files, run their database rebuild to update them.I always put modified AFCADs in the holder to insure they get the highest priority as the scenery designers intended.

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Wow..... thanks for all the help. I do appreciate!OK.....first of, I cannot log onto navdata.com. The site appears to be down.Second of... I actually have AFX, and I have gone in and changed the properties of those two ILS'es, by taking out the back course for both.We are just getting the full force of a thunder storm with severe lightning, so I am about to shut down my pc's. The power is already fluctuating!!!!Will report back.

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Ron's solution hits right on. Microslop shouldn't have backcourse enabled for all approaches, which they do, but only those with published backcourse approaches.Someone suggested getting a sidstar from navdata... don't do this unless you want something that is more than a year old. Besides, it has nothing to do with the problem. The ILS info used by the FMC comes from the navdata, not the sidstars.

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>Ron's solution hits right on. Microslop shouldn't have>backcourse enabled for all approaches, which they do, but only>those with published backcourse approaches.>>Someone suggested getting a sidstar from navdata... don't do>this unless you want something that is more than a year old.>Besides, it has nothing to do with the problem. The ILS info>used by the FMC comes from the navdata, not the sidstars.the navdata, sids/stars are all in the same file. or so i thought.

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Kevin: In a word, nope. Navdata is a small collection of files that define the world for navigation. All airports, runways, fixes and airways are defined here. SIDSTARs are a large collection of files, one for each airport, that define the terminal procedures for that location including arrivals, departures and approaches.The problem with navdata.at as a source for sidstars is it had to stop accepting uploads from the community that was creating these files when Navigraph started providing navdata and sidstars in the same download (seems like the same file unless you look at what it actually does).

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