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cathay747

PMDG 777 false terrain alarm

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Same here.

 

Cause it happens only with the T7 it has nothing to do with anything but with the T7.

 

I suspect the fix is easy but so far no one seems to have found it.

 

I will monitor very close this thread because the terrain warning is very disturbing during a landing.

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Same here.

 

Cause it happens only with the T7 it has nothing to do with anything but with the T7.

 

I suspect the fix is easy but so far no one seems to have found it.

 

I will monitor very close this thread because the terrain warning is very disturbing during a landing.

I am glad to have someone, who have also encountered this troubling issue to share my worries with and I do hope that a solution, either it is in the form of an update or something else, is in reach or available in the near future.

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I am glad to have someone, who have also encountered this troubling issue to share my worries with and I do hope that a solution, either it is in the form of an update or something else, is in reach or available in the near future.

Moreover, if it is possible, can MarkII also help to get us a screenshot of the false terrain alarm during landing as I could not, due to the fact that my computer has malfunctioned, as I have mentioned before.

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Same here too. But for me is start after I upgrade the AIRAC cycle to 1502. First with cycle 1408 never happend. So I search a little and I found on FCOM1 at Boeing limitation this:

 

"Enhanced GPWS:

•Do not use the terrain display for navigation.
Do not use the look-ahead terrain alerting and terrain display functions within 15 nm of takeoff, approach or landing at an airport not contained in the GPWS terrain database."

 

So the questions are:

 

1.Does it missing something like airport database on EGPWS?

2.Has something to do with AIRAC CYCLE?

 

Because I repeat for me it starting after I change the AIRAC cycle.

 

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The EGPWS terrain database, which triggered look ahead warnings, is installed with the 777. It's nothing to do with the AIRAC.


ki9cAAb.jpg

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[quote name="Artur Munteanu" post="3183316" timestamp="1424507367"

Do not use the look-ahead terrain alerting and terrain display functions within 15 nm of takeoff, approach or landing at an airport not contained in the GPWS terrain database.

 

Can you elaborate on this sentence?

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I have this problem too. Encountered it recently on final for ENCN, ENGM and ESSA.

Flap 30, autobreak 3, speed break armed, captured ILS and glideslope. Disconnecting AP and AT at approx 2000 ft agl. Gears are fully down and green light at 20 flaps, and 30 flaps green light around 1000 ft agl. Vspeeds and autobreak level is set before descent. Local QNH is set at TL.

 

I get terrain warning approx 800 ft above agl + pull up, pull up. It continues till about 20 ft. I do not hear any of the approach callouts (500 ft, 400 ft etc).


Andreas Stangenes

http://www.youtube.com/user/krsans78
Add me on gamertag: Bullhorns78

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Do not use the look-ahead terrain alerting and terrain display functions within 15 nm of takeoff, approach or landing at an airport not contained in the GPWS terrain database.

 

Can you elaborate on this sentence?

What sentence? What do you mean?

Just read on Boeing FCOMv1 at page 187.

 

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OK, problem SOLVED!!!

No more false alarm terrain in aproach. Don't ask me what does it has to do but,I reinstalled the AIRAC Cycle 1408 and everithyng works good now. (for me at least). I don't say that this is the solution, but now return all to normal, without false allarm in cockpit. And I still think that the GPWS airport database is reading from FMC database.

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OK, problem SOLVED!!!

No more false alarm terrain in aproach. Don't ask me what does it has to do but,I reinstalled the AIRAC Cycle 1408 and everithyng works good now. (for me at least). I don't say that this is the solution, but now return all to normal, without false allarm in cockpit. And I still think that the GPWS airport database is reading from FMC database.

Then may I politely ask how does one install an AIRAC cycle?

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Then may I politely ask how does one install an AIRAC cycle?

Go to Navigraph and purchase a cycle or a year and use their FMS Data Manager (free).  Here:  http://www.navigraph.com/

 

I'm not buying the claim that navdata has anything to do with GPWS.. I used to think it did but I was convinced otherwise a couple of weeks ago.  I'd need proof.


Dan Downs KCRP

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Go to Navigraph and purchase a cycle or a year and use their FMS Data Manager (free). Here: http://www.navigraph.com/

 

I'm not buying the claim that navdata has anything to do with GPWS.. I used to think it did but I was convinced otherwise a couple of weeks ago. I'd need proof.

well since you claimed that downgrading your AIRAC cycle (navdata) from 1502 to 1408 have solved the problem, hence I think the newest navdata, which may have came from the installation of the 777 itself, may have been at fault.

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I'll try to explain a little this confusion.

 

In the real aviation world, The EGPWS is produced by Honeywell (just Google to see more) and of course they have they're own software update and upgrade regular, just like the FMC installed on the Aircraft. So when a new airpost is born or open, the database with terrain and civil airports (the only airport that are not includeed in EGPWS are the military  airports )are included in their update, and the aviation company are regular updating the softwars of their Aircraft. This happend also with FMC.

 

Now, in a simulator (I am talking about FSX not real world simulator wich cost 10 million dollars like the A380 simulator from Dubai airport), you also update you're FMC cycle (if you wan't it's not a request!) and so you can have new star, sid procedure, and also new airports database. But, you only update the FMC software, I've never heard that there is an update for FSX or P3D or else for the EGPWS, neither PMDG or Aerosoft or someone else tlk about this, but when you fly you're EGPWS in you're sim works so you do'n't have false terrain allarm. Otherwise, how the EGPWS know that you are landing in a civil airport and not in a mountain or a desert??? It has to read this data from somewhere, and the only airport.dat is in Navdata folder of you're sim, for ex. mine is C:\FSX\PMDG\Navdata.

 

So, the EGPWS IT HAS TO READ the information from the FMC, there is no doubt for me, but this is my logical and personal opinion, I have no clue about xml files used for the simulator, so what I am saying maybe wrong.

 

But I repeat, I've downgraded the AIRAC cycle, and no false allarm terrain. When I installed the 1502 cycle, it started at first flight, and I fly in Dubai Int, (OMDB), at Athen (LGAV), Wienn (LOWW), Heathrow (EGLL) and all are not the default scenary, but from Fly Tampa or Aerosoft, so nothing is wrong with them. Is a problem wich it HAS to do absolutly with AIRAC Cycle.

BTW the cycle used by PMDG released with the 777 is not 1408, not 1502, but 0913 wich expired in mid. settember 2013! (the numbers of the cycle indicate the date ex: 0913 = sett 2013, 1502 = feb. 2015 and so on)

 

 

 

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I'll try to explain a little this confusion.

 

In the real aviation world, The EGPWS is produced by Honeywell (just Google to see more) and of course they have they're own software update and upgrade regular, just like the FMC installed on the Aircraft. So when a new airpost is born or open, the database with terrain and civil airports (the only airport that are not includeed in EGPWS are the military airports )are included in their update, and the aviation company are regular updating the softwars of their Aircraft. This happend also with FMC.

What you say is basically correct but EGPWS terrain database updates are not frequent updates like monthly nav data.

 

So, the EGPWS IT HAS TO READ the information from the FMC, there is no doubt for me, but this is my logical and personal opinion, I have no clue about xml files used for the simulator, so what I am saying maybe wrong.

As far as I know the EGPWS does not read FMC information for this purpose. The warning in the FCOM refers to not using terrain look ahead warnings if the airport and surrounding area has not been modelled in detail in the terrain database. The FMC does not contain anything other than spot heights for airports and radio stations. No use for EGPWS.

 

If the problem was the AIRAC everybody would see the same problem at these airports. It's highly unlikely that AIRAC elevation data would change from one cycle to another for a long established airport.


ki9cAAb.jpg

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does the term "terrain look ahead warnings" refer to the terrain radar?

 

but when the terrain warning sounds, the radar lights up immediately...

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