"Terrain Terrain"

[J D ADAM]

Greetings Gentlemen,

Could somebody please inform me what the criteria is for setting off the "terrain terrain" warning.
I ask this because on several occasions this warning has been set off whilst stable on a glide slope.
This has happened on approach to NZCH  when one is flying over the Canterbury Plains. Also  VHH which I perhaps I understand more readily where there are surrounding hills.
Does one ignore this warning in 0/0 conditions.

Thank you
Derek Adam
NZAA

[John H Watson]

Were you approaching runway 02?

I can't think why it would be triggered. Can you recall your aircraft height above terrain, airspeed and flap/gear configuration? There are graphs showing height vs terrain closure rate, but submodes are activated depending on distance from airport and configuration.

Where there is unusual terrain, the warning envelope can be modified by the manufacturer.

[Hardy Heinlin]

Hi Derek,

I just flew the Rwy 02 ILS in PSX and got no warning.

The Mode 2 alert criteria are illustrated in the Aerowinx manual, page 547.

Fast rising terrain will trigger this alert.

Do you use an external scenery generator?


Regards,

|-|ardy

[J D ADAM]

Hi Hardy and John,

  Thank you for you replies.

I have repeated my approaches to VHHH 07L and NZCH 20 and received no warning from either !!!!!!!!

I do use P3D5  for a scenery generator in association with External Sim Router.

My understanding of horizontal PAPi's is that 3 whites and one red is the accepted path guidance for the 744
and would be happy to be corrected on this.

However with my scenery generator I often get two and sometimes three reds I have always put this down to the fact that the positioning of the two programs may not be the same in the sim world.

Although once holding a PPL and coped successfully on the Air New Zealand  simulator (now defunct) I find it difficult to land PSX.  I guess i would become a very successful button pusher as a commercial pilot!
The old dog and pilot syndrome.

Hardy
Finally I want to add to the adulation you have received on the production of PSX and of late NG FMC. There is not a flight go by when I see something that blows me away admiring the programming skills you have produced for our complete enjoyment. You are a genius.

With grateful thanks

Derek

[cavaricooper]

Derek-

Was that a typo or can you confirm that ExternalSim is working with v5?  I am aware the Beta is underway and it would be great to know that this is future proof.

Also, if you are the NZ Derek with the presets, a certain amount of gratitude must flow your way as well.

Ta mate- C

[Britjet]

Hi Derek,

It's 2 whites, 2 reds, as for other types. The flight deck height discrepancy is very small at distance so it isn't a factor.
The guidance for the 747 is that below 300ft the visual guidance should be ignored (unless it's obviously all red or all white etc).
If you fly a 2/2 approach you will find that the PAPIs tend to go on the "white" sid in the last 100ft or so.
This is normal and is where the flight deck height becomes a factor.
Peter

[J D ADAM]

Hi,   

Yes it was a typo  should have been P3D4.5 !  No is wasn't me in NZ in fact I do not think anybody else in NZ fly PSX  which is a disappointment because of the many questions I have . How I miss my late Brother who was a sim instructor with ANZ.
Thank you Peter for your advice (and the fine videos you have produced).

However with my scenery generator I often get two and sometimes three reds I have always put this down to the fact that the positioning of the two programs may not be the same in the sim world.

Does anybody else experience this with P3D4.5?

Cheers
Derek