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cagrikartal

Faulty 1000 callout on radio altimeter

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Hi folks

 

I don't know if this has been discused here before (i ve made a search and found nothing) but here is a strange problem i ve been having since the latest updates of the t7. The problem is, i m getting  the 1000 callout when my radio altimeters says i'm about 1200 feet above ground some times even higher. i have a clean fsx without much addons excepts the ones that bring the reality to it like pfpx or asn or topcat etc. So no global scenery what so ever. (a few free airports but the problem is happening even when flying to default airports )

 

I have other callouts working fine only the 1000ft alert  and it only heppens with the 777-300er/200lr Not with the ngx.

 

Anyone having this problem ?

 

Thank you

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The 1000 ft voice alert is based on the barometric altimeter and not on the radio altimeter, so it is 1000ft AAL (above airport elevation). All the other callouts are based on the radio altimeter.

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The 1000 ft voice alert is based on the barometric altimeter and not on the radio altimeter, so it is 1000ft AAL (above airport elevation). All the other callouts are based on the radio altimeter.

but is it the same for a 737 ? because in the same conditions the ngx's 1000ft alert comes exactly at 1000ft.

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but is it the same for a 737 ? because in the same conditions the ngx's 1000ft alert comes exactly at 1000ft.

There is a recent thread (past several days) in the NGX forum, It appears the NGX 1000 foot callout is based upon radio altimeter when it should be barometric per FCOM2. It would appear that the T7 is correct and the NGX is messed up

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There is a recent thread (past several days) in the NGX forum, It appears the NGX 1000 foot callout is based upon radio altimeter when it should be barometric per FCOM2. It would appear that the T7 is correct and the NGX is messed up

The NGX is correct too. As was pointed out in that thread.

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The NGX is correct too. As was pointed out in that thread.

Does this look like the NGX is correct based upon the last post in that thread. By VOZ102 "I have actually done a test in the sim and all my 1000ft callouts are happening based on the radio altitude. Anyone from PMDG care to confirm?"

 

I have only been able to check this twice. The first time the altitudes were too close to make a difference. The second time it was the radio altimeter that was called out at radio altitude of 1000 and barometric altitude was at 1030.

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Does this look like the NGX is correct based upon the last post in that thread. By VOZ102 "I have actually done a test in the sim and all my 1000ft callouts are happening based on the radio altitude. Anyone from PMDG care to confirm?"

 

I have only been able to check this twice. The first time the altitudes were too close to make a difference. The second time it was the radio altimeter that was called out at radio altitude of 1000 and barometric altitude was at 1030.

Sorry Michael, I was about to come back and edit my post. I've just checked this in my NGX and you're correct, the NGX callouts are all radio alt based. I must have been flying the 777 when I noticed the 1000 ft call wasn't at 1000 RA and wondered why that was. My mistake, never assume if it's right in one PMDG sim it will be right in another. Hopefully it's on the list for SP2.

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Kevin

I just landed at EDDF ILS 25L in the 777F and both the 500 and 1000 callouts were based upon radio altimeter. In both instances the barometric altitude was about 300 ft. above the callouts. So it looks like both the NGX and 777F the 500 and 1000 callouts are based upon radio altimeter. This is crazy but consistent.

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Kevin

I just landed at EDDF ILS 25L in the 777F and both the 500 and 1000 callouts were based upon radio altimeter. In both instances the barometric altitude was about 300 ft. above the callouts. So it looks like both the NGX and 777F the 500 and 1000 callouts are based upon radio altimeter. This is crazy but consistent.

It's height above field remember, field being set by the FMC destination. Try it somewhere where terrain is not flat on approach. EGKK is where I noticed it. Or to an airport with a different elevation to the once set up for approach. Then you will see the fallout occurs at a at the baro-field setting not RA.

 

The 777 works correctly at 1000ft, the NGX uses RA.

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EGKK is where I noticed it.

I will try EKGG. 8R or 26L or does it make any difference?

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I will try EKGG. 8R or 26L or does it make any difference?

I can't remember which I noticed it on, but I think they both have terrain that is obvious at the 1000 ft point. Another place to try would be Leed/Bradford (EGNM). That has highish terrain when approaching from the west.

 

edit: looking at the chart a hill is marked for the 26L approach.

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There is a recent thread (past several days) in the NGX forum, It appears the NGX 1000 foot callout is based upon radio altimeter when it should be barometric per FCOM2. It would appear that the T7 is correct and the NGX is messed up

 

 

It's height above field remember, field being set by the FMC destination. Try it somewhere where terrain is not flat on approach. EGKK is where I noticed it. Or to an airport with a different elevation to the once set up for approach. Then you will see the fallout occurs at a at the baro-field setting not RA.

 

The 777 works correctly at 1000ft, the NGX uses RA.

 

Thank you both for helping out. just to make sure if i got it right; if the airport elevation is lets say 800ft above sea level you will hear the 1000 callout around 1800 ft  msl.Right ?

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Thank you both for helping out. just to make sure if i got it right; if the airport elevation is lets say 800ft above sea level you will hear the 1000 callout around 1800 ft  msl.Right ?

Yes that's how it should be. Also the 500 ft call.

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Thank you both for helping out. just to make sure if i got it right; if the airport elevation is lets say 800ft above sea level you will hear the 1000 callout around 1800 ft  msl.Right ?

It seems to work that way. I am going to try EGKK tonight. If it is any different I will let you know.

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It seems to work that way. I am going to try EGKK tonight. If it is any different I will let you know.

I just tride it egkk 26l. I think it works that way. The airport elev on the fmc was 203 and i got the 1000 callout at 1200 msl (960agl).

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EGKK is where I noticed it. Or to an airport with a different elevation to the once set up for approach.

 

It's EGKK not EKGG and I agree, always on 26L approach.

 

I flew all the way from KLAX (11hrs.) and never saw a hill on either the radio altimeter, Navigraph chart for 26L, or out the cockpit windows. What a disappointment. But it was a nice flight.

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I flew all the way from KLAX (11hrs.) and never saw a hill on either the radio altimeter, Navigraph chart for 26L, or out the cockpit windows. What a disappointment. But it was a nice flight.

You could always have done a circuit starting from Gatwick. The terrain profile is shown on CAA charts.

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try something around lemd you shoud have some egpws calls ....

You could always have done a circuit starting from Gatwick. The terrain profile is shown on CAA charts.

 

I am going to pass on all of this and stay in the United States.

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I am going to pass on all of this and stay in the United States.

Well I'm sure you will find an airport that has high or low terrain on aproach there as well. I don't know any off hand but there must be some.

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