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ACA034137

Terrain Terrain warning

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Hi Guys,

 

Finally brought the T7 into PANC today, and from about 2500 ft down, on the VNAV profile, the terrain avoidance warning screamed the entire way down.  I was over water most of the time.  I was using Aerosoft's PANC scenery....

 

Anybody else experience this?  Was there something I might have been doing wrong?

 

 

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Someone with more knowledge than me can confirm or deny this, but I believe that below 2,500ft the systems check to see if you're in landing config. Since gear up and flap 15 below 2,500ft isn't a landing config the system has to assume you're in a CFIT (controlled flight into terrain) and set off the terrain warning.

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I had a similar occurrence once. GPWS accompanied me all the way down to the runway, first with "terrain" announcements and then "pull up." Gear was down, flaps 30, good landing speed. I still don't know what caused it and haven't been able to duplicate it since.

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Ya, the warning continued right down through gear extension and flaps 30, all the way to the runway.  Luckily the inhibit button was not out of reach.

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I have had nuisance terrain warnings as well.

I have also had no terrain warning while flying straight at a mountain!

 

The thing is, in real life, the GPWS uses a terrain data base.

I have updated FSX terrain with FSGenesis mesh worldwide.

Now what terrain data base does the PMDG777 database use?

 

Does it use a PMDG database that differs from the FSX database as well as my personal database?

Or does it use the standard FSX terrain database (which also differs from what I see out the window cause I use FSGenesis Mesh)

Or does it read and use my personal terrain database?

Someone with more knowledge than me can confirm or deny this, but I believe that below 2,500ft the systems check to see if you're in landing config. Since gear up and flap 15 below 2,500ft isn't a landing config the system has to assume you're in a CFIT (controlled flight into terrain) and set off the terrain warning.

That is probably windshear you are thinking of. The PWS (Predictive) starts scanning on approach from 2300ft. Windshear warnings are given once below 1500ft (or 1200ft in case of predictive windsear).

Ya, the warning continued right down through gear extension and flaps 30, all the way to the runway.  Luckily the inhibit button was not out of reach.

which means the warning was not due to flaps or gear. There are quite a few different aural warnings, all similar, but they all mean something different. Look in the back of the systems decription manual under Warning Systems. For instance the "TOO LOW TERRAIN' warning means "Descent below unsafe altitude while too far from any airport in the terrain database." And if PANC is not in the PMDG terrain database (or whatever database it uses) then you get a nuisance warning.

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It occurred to me just now when landing at LXGB, and it has occurred for several times.

 

But I agree with fsgeek. 

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I ve had the same problem on takeoff actualy right after the nose gear lifts off. Ive had this first time today but it happened 3 times.(i flew the t3 3 tiles). Whats actualy happens is the terrain warning kicks in while i takeoff and says "pull up, pull up" until some where 1500ft agl. And there is no terrain ofcours on the nd on my way.

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I have had this occur to me as well, in full landing configuration and on an ILS.

It has happened at several airports, two I recall are EINN and EICK.

Roberto

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 I've never had this with the NGX and only once in the 777 while approaching an landing at Innsbruck.

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Ive solved my problem by switching the panel state from custom to the pmdg cld drk, i hope this helps.

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ok, but what is the diffrence between short and long state ?

 

long = on ground power and air

 

short = on apu

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Hi Guys,

 

Finally brought the T7 into PANC today, and from about 2500 ft down, on the VNAV profile, the terrain avoidance warning screamed the entire way down. I was over water most of the time. I was using Aerosoft's PANC scenery....

 

Anybody else experience this? Was there something I might have been doing wrong?

I flew from KJFK to PANC today. Approach into PANC ILS07R without problems. No terrain or config warnings. I did a go around and levelled off in 1000ft, continuing straight at the mountains. A few miles before impact I got the "Caution Tarrain" aural warning but I continued and maintained 1000ft. Then a little later came the "terrain terrain pull up" aural warning. Everything according to the book. Beautifull :-)

Full throttle + 20 pitch (also according the books terrain avoidance maneuver) got me clear of terrain.

 

I have Aerosoft PANC with UTX Alaska and FSGenesis for terrain mesh.

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