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737-800 Fmc Error Message

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Hi chaps!Am having a nightmare of a time searching this in the forums. Consistently when I fly into YMHB with the 737, I get some sort of FMC message prior to approach for the ILS12. It goes something like "RWY/CRS APP ERROR", or something like that. As far as I know, I am doing things right, but I am not that familiar with the 737. I have entered the ILS frequency into both navigation radios, have heading and course selectors set to approach heading etc. The one thing I notice is that in the FMC, on the approach page, it gives 109.90/132 as the FREQ/CRS. On the PFD, in white, it says 109.90/120. 120 seems to be the correct one, as per latest charts. This is the frequency I have entered into the CRS and HDG MCP windows. Am I doing something wrong?Thanks for any help anyone may be able to offer!Rudy

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Hello Rudy,Even if the correct rwy course is 120 you will still get the error msg unless you enter 132 in the course MCP. The FMC takes into account the course in it's Airac database not the FS or RW one.Happy new year!

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A 12 deg difference between courses is unusual, normal variation is 2-3 degrees. Also, if the current charts indicate 120 for the course then the navdata should also have the current data. I wonder why the large difference. One thing that I suspect is the white numbers on the PFC come from the MSFS and it is very odd that current charts agree with MSFS (because their navdata was old years ago). I wonder why the charts agree with MSFS and not current navdata?

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Indeed, such a difference is not normal. After reading Dan's post I took a look at the data for Hobart. I'm not familiar with this area of the world so I didn't want to speculate on anything earlier.The default FS9 (and probably FSX) runway heading for RWY12 YMHB is 118 degrees. Maybe there is a wrongly modified Afcad involved?EDIT: Ok, I conducted a trial with my 737, Airac 0311, very old! My FMC indicates 119 degrees with the FS default data as 120 degrees. Disregard the 118 degrees I mentioned earlier.

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I am sorry chaps, I have lead you all up the garden path!!!! I meant to type 122, not 132!!! Sorry, the PFD and charts say 109.90/120, the airac/FMC says 122. The airac is 0809.I get the error having entered 120 into CRS and HDG windows on the MCP. I suppose I should have it set to 122, in order to agree with the AIRAC, and then I won't get the error?I also noticed, after engaging APP mode and both autopilots, LOC and G/S were green on the PFD, and speed was being maintained by the autothrottle in ARM mode. Is this normal? Once I disconnected the autothrottle and reconnected it on approach, I could not get it to engage in SPD mode, or any other mode that controlled my speed for that matter. I imagine this is all a side-effect of the earlier error it gave me before approach? SINGLE CH was also annunciated.Gosh, sorry about that misleading typo, and thanks for your helpful replies!CheersRudy

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The latest charts should agree with the latest navdata; regardless, the error will go away if you select the course that is shown on the APPR page and that value comes from the navdata. The only thing it affects is the orientation of the HSI display when the ND is in APPR mode since a localizer only has one course.Single CH will be annunciated until about 1500 agl (or maybe 1000, I can't remember) then it will do a self check and use both channels. The throttle was ARM probably because you were deaccelerating? The autothrottle should work for approach, flare and touchdown by auto-retarding. All you need to do manually is put her in reverse thrust.

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