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Guest pilotex2

PMDG 747X - Sink rate warnings

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Recently I have noticed that when landing this bird, the PMDG 747X, I keep getting repeated warnings like "Don't sink" or "Sink Rate" and this is while everything looks normal (to me at least). I am descending at an acceptable rate of around 700 ftpm and I am established on the localizer and GS. This happens when doing an CATIII autoland AND when I fly her by hand. I am 99.9% sure that there is something I am doing wrong here that I keep getting these warnings which become frustrating especially when the GPWS starts counting down. Any help/input would be greatly appreciated!Thanks in advance,

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Anyone??!! :(
HiThe "Don't Sink" warning should only be heard after a loss of altitude usually after takeoff or G/A. However the "Sink rate" warning fits your scenario better as it would indicate an excessive descent rate during landing. Are you experiencing this everywhere or is it only at some airports? If you have the latest AIRAC or scenery installed, it might be caused by old fsx ils systems messing things up on approach. Some screenshots would be nice though.EDIT: I write fast, so I might edit the text a few times, make sure you update the page ; )CaptEm

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Thanks for the comment. As far as I recall, I hear the "Don't Sink" warning once and after that it is the "Sink Rate" warning that kept on getting repeated. I am using default FSX AIRAC and default PMDG nav data as well. I just did a quick flight right now and a full manual landing and I didn't hear the sink rate warning even once! :( Usually though, I hear at at different airports when landing that is. Here are some screenshots from the flight I did today although everything will look normal.Image_2009-01-30121347687.jpgImage_2009-01-30121440468.jpgImage_2009-01-30121539781.jpg

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Those sceenshots dont look normal, somethings really messed up there. Your in V/S and alt hold descending with autopilot off. I'm off out now but those pictures will help others figure it out.Rob

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Those sceenshots dont look normal, somethings really messed up there. Your in V/S and alt hold descending with autopilot off. I'm off out now but those pictures will help others figure it out.Rob
Pretty messy approach, but everything looks normal as far as I can see. He's not in V/S mode, and he probably disc a/p at 4000ft after it went into hold mode. If you keep getting the warnings take some screenshots of it and post them here and we'll look into it.CaptEm

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Yes, I know, I wasn't lined up and everything but believe it or not I put her down on the tarmac. :( Anyways, that's not the point. No I wasn't in V/S mode. As I mentioned, I turned off AP and was flying her by hand thus the messy approach. The A/T was controlling my speed. But yea I will do some flights with the 744 and once I get those warnings I will take some screenshots and hopefully you guys can tell me what I am doing wrong.Thanks!

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For one thing, the flaps should be at full, not 25 degrees in those pics at that stage of the approach.

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I had the Vref for Flaps 25. Usually though I set the flaps to 30 degrees but this time I decided to try the approach with 25. In the real world do they usually do 25 for approach? I thought you could do either one since it's in the FMC.

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I had the Vref for Flaps 25. Usually though I set the flaps to 30 degrees but this time I decided to try the approach with 25. In the real world do they usually do 25 for approach? I thought you could do either one since it's in the FMC.
In the real world you can do either 25 or 30. They are considered to be your landing flaps, having said that it is "normal" to use flaps 30 for the approach but either way pending on the PMDG coding the GPWS will work the same for either.You said that this one worked fine for you so the screen shots dont really help. Sink Rate is due to excessive decent rate and should not be linked in any way to the ILS or the FMC selected information and airport but then this is FS so it may have some link there. As requested above post screen shots of it happening. I assume you are using the replay to make the screen shots, try and get it when you are actually getting the warning.

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While I look for an opportunity to take more screenshots, I had another question. What does it exactly mean when you hear "Glideslope" on approach?

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While I look for an opportunity to take more screenshots, I had another question. What does it exactly mean when you hear "Glideslope" on approach?
The GPWS "Glideslope" aural warning activates when the aircraft descends half a dot below the glide path.

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The GPWS "Glideslope" aural warning activates when the aircraft descends half a dot below the glide path.
:( For the AlliedSignal GPWS it is normally triggered at 1.3dots... not that it is important. I am not sure what the PMDG version is coded to.

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I am coming to the conclusion that this is bug in FSX but I could be wrong. Here are some screenshots. I was constantly getting the "Don't sink" and "Sink Rate" warnings; all the way down to about 100 AGL.Image_2009-02-15225554171.jpgImage_2009-02-15225559875.jpgImage_2009-02-15225603578.jpgAny input would be appreciated!

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I am coming to the conclusion that this is bug in FSX but I could be wrong. Here are some screenshots. I was constantly getting the "Don't sink" and "Sink Rate" warnings; all the way down to about 100 AGL.Image_2009-02-15225554171.jpgImage_2009-02-15225559875.jpgImage_2009-02-15225603578.jpgAny input would be appreciated!
Hmmm I think i am seeing the problem for you....I think you need to refresh yourself on the whole setting the Barometer thing. I notice you are established on final and your Baro is set to 29.92 this is the standard pressure above transition altitude usually 18000 feet...so you are not setting the proper pressure beneath transition altitude if you listen to the ATIS report usually about 50 miles out while on descent it will give you the pressure underneath transition altitude.If you do not set it correctly your instruments are indicating an incorrect altitute. So although you think you are only 500feet above ground its highly possible that you are in fact only 300 feet due to pressure differences. I am not a pilot so I am not the most knowledgable about all the ins and outs, but I think that is your issue. Hope this helps! Guthrie Zuehlke

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