GPWS Terrain and Pull Up Warning on final approach

[jf_aero67 1]

Hi All,

 

I have just this last couple of days started encountering an issue with the GPWS / EGPWS on the -800 and -600 737NGX.

 

On final approach, stabilised - gear down, 30 deg flap, approx 140 kt and 700' RoD, on localiser and glideslope, I get "Terrain" alerts on final, followed by "Pull Up" on short final.

Same if I hand-fly or use the automatics where everything is on the numbers.

 

I have tried various airports across the  US and Australia - same deal.

I should point out that this also occurs in flat terrain - eg  flying into flat desert airfields

If I have Terrain displayed on the ND, the airport is highlighted in solid yellow (I think this was the behaviour before) and there is also a solid red block (smaller) near it (don't recall this from before);

There is also a full forward field of dotted yellow that I don't recall seeing before.

 

The only changes I recall that I have made to my system recently:

• Re-downloaded & re-installed the updated FSUIPC (registered) after the recent code-signing problem that was announced by Sim Market on 6th May.

 

 

 

Only way to suppress it is to pull the terrain inhibit switch on the co-pilots side. Any ideas anyone?

Thanks for any input

 

cheers

Jonathan Fyfe

 

 

[Klocek 0]

Also, i would like to add an observation concerning gpws test sounds, they do not correspond to the ones user chooses in the fmc, for example if you have chosen "decision height" call-out you will hear "minimums" when testing gpws, is that normal?

[jf_aero67 1]

Ok good news, problem solved, turns out it was my own doing.

I added some additional navdata to the PMDG navdata files, but without sorting it by descending by latitude.

-airports.dat

-wpNavAID.txt

-wpNavFIX.txt

 

This sorting requirement is outlined in the PMDG Navdata Glossary in the knowledge base.

Thanks to Ryan Maziarz at PMDG support for identifying the issue!

[lawson23 1]

push the button beside the PFD,the "glide slope" and "terrain terrain" will be not work.

[jf_aero67 1]

To clarify my answer, I had made additions to the PMDG navdata and that was the cause of the issue.

The data was added without paying heed to the sorting requirement. (IE I just added new entries at the top of the data listings).

Re-instating the original navdata files confirmed the issue was no longer demonstrated.

I then once again added new data to the files, but inserted it in the correct positions in the files IE sorted by latitude.

I tested again, and the issue was no longer demonstrated.

Problem solved.

cheers

Jonathan Fyfe