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Alex Kulak

NGX WXR var?

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what is VAR and why does it only show up better weather when its twisted all the way to the right. its the gain. but it was stormy and raining hard in KPIt today and without var there was very little everything then i turned my gain all the way to the right and got alot better weather coverage on my cdu.

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what is VAR and why does it only show up better weather when its twisted all the way to the right. its the gain. but it was stormy and raining hard in KPIt today and without var there was very little everything then i turned my gain all the way to the right and got alot better weather coverage on my cdu.

 

It just means that manual GAIN is being used.

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Gain 'basically' increases the sensitivity of the radar.

Gain 'basically' increases/decreases the sensitivity of the radar.

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and got alot better weather coverage on my cdu.

That's not actually true.

The standard detent for the gain knob is (or should be, it differs from aircraft to aircraft, even within the same model) a calibrated setting. Hence, with a little experience, a pilot can guesstimate the severity of the weather in front of him, not only by the colour of the returns, but also by the amount/spread/coverage/...

You don't get "better" coverage when turning the gain knob up, you get amplified coverage. Those two are not the same.

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Hey guys,

 

this is a point I´m struggling with too. As Alex wrote I don´t get many echos even in severe weather with the NGX WXR. I compared the situations with the T7 which seems show a more detailled picture of the wx arround.(Yes, I´m using ASN. Yes, I´ve swiched WXR on.  :lol:  )

I´m aware of the way a WXR works but I´ve to "open" the gain to get a compareable image to the T7 without using the gain.

 

Maybe you could alight me  :Idea:

 

Anyway, I´m very happy with the SP1D, thanks a lot!

 

 

BRGDS

Christian Hoch

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Disclaimer: I'm not an NGX flyer, so I can't be too specific. However, in general terms:

 

The AUTO gain position is (should be) calibrated so as to display the most dangerous returns without cluttering the map with every drop of precipitation. Most of the time, you should leave the gain in AUTO for this reason.

 

Tilt, on the other hand, is generally best manually controlled. What are you doing with the tilt control? Ground returns are not currently modelled AFAIK, which does make it slightly more difficult to find the optimum tilt setting; generally you want to be pointing the radar beam in to the core of the storm. At higher levels with an incorrect tilt setting you are unlikely to get many returns as ice is far less reflective than rain.

 

The gain control may be moved out of auto in order to assess which cells are the most powerful; generally this would involve turning the gain down slowly and seeing which returns remain the longest whilst others disappear. However, the gain should usually be returned to auto after this assessment has been made. The aim of the game to to separate harmless rain showers from dangerous storm cells.

 

Having said all of that, as I say, I've not experienced the NGX's behaviour for myself so I can't tell you whether there's an underlying issue with the way the auto gain is calibrated -- perhaps somebody else can!

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What Simon said.

 

 

 

Also, remember guys, that precip isn't the issue. What you're interested in is avoiding storms, which are generally associated with stronger returns on the radar. It's generally not the green banding that you need to be concerned with, so, despite it being something you're probably used to (from watching the news, or the "cloud finder" radars of the past), you don't need to "fill in the holes" or "make it look better" by adjusting the gain unless you're trying to get a temporary picture of the layout of the storm. As an example, if I saw two potential gaps that I could cut through, I might want to up the gain temporarily to see if there are slightly stronger returns in one gap versus the other.

 

It's kinda like the MCP. A lot of the time, you let the automagic handle it in LNAV/VNAV, but there are times where you want to take it out of that auto mode to tactically handle the situation (V/S, HDG SEL and so on).

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Hey Kyle, waiting for you video about wx radar, when you have some spare time to do it.Thanks.

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Hey guys,

 

I think I've been misunderstood. I'm not interested in a "better look" or "filled holes". And I'm aware how a WXR works.

Anyway thanks to Simon and Kyle for the explanations!

 

As I understood are the wx radars of the PMDGs T7 and NGs both using the same ASN output and the same programming technology. Based on this I supposed to get the same radar image in the very same situation but they are different. With the T7 WXR in "auto mode" and the NG WXR gain turned to the three-o-clock position they are comparable but still different.

That's what I'm curious about. Why are they different with the same input?

 

It's easier to handle a system you understand and know ;)

 

BRGDS,

Chris Hoch

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