Winds - Which data to input?

[XCLTM3 112]

Hoping someone can clarify this for me. I only fly the NGX.

 

When sitting on the ground at Gate and gathering all the data for the pre-flight (CDU, etc - ie: FS2 Crew), I have noticed that there is a 12 degree variation between what ATIS is calling and what the Nav Display indicates (in addition to what FS RealWX indicates) ?

 

To clarify, for eg right now I'm sitting at YMML Gate C12. I'm using FSRealWX to gather the weather data and send it to FSX. FSRealWX indicates winds 250@05. Nav Display concurs. FSX ATIS however is calling 238@05? This is not the first time I've noticed this incongruity. It is always 12 degrees. I understand it may be MagVar and difference between True etc.

 

Ultimately my question is this: which wind data do you input into the CDU/FMC? ATIS, or FSRealWX Metar report?

 

Thanks in advance.

 

 

Steve

[Mandy 0]

Use the values ​​that come from the ATIS of FSX.

The reason is the airport height is different from the first "real"

Wind data. Example: Airport: 1000ft. First Wind layer: 1080ft.

FSrealWX try to calculate the missing part. (Interpolated)

 

If you use the version v1.06.1449 DEV? In Europe, I have not more than 5 ° deviation from the real weather.

 

Please excuse my bad English!

 

Best regards!

 

Mandy Broschk

[Petr Bily 0]

Hi Thomas,

 

I fly only VATSIM so I get wind which can be 30 minutes delayed. Like in the real life. So put there information from ATIS because we want to fly like in reality. If you fly VATSIM you get wind info from ATC together with take off clearance.

 

Petr

[SE-KMG 2]

I would say that on use True and the other magnetic, since you say that it is always 12 degrees.

 

The magnetic declination for Melbourn is 11.34 (Source:http://magnetic-declination.com/)

So round that up and you get 12 degrees easterly variation.

 

All winds from the ATIS is reported in in degrees magnetic so it is that value you should put in the CDU.

Unless you are flying on your true heading, which is mostly done near the NP, then you have to consider the wind to respect of true north.

 

Another little thing off topic, is that ATIS do not report exact degree, like 238, it is rounded up to nearest whole tenth of degree, 240.

Also, what you put in the CDU is just to give a brief picture of what to come. Weather and specially wind changes constantly. What you get in the ATIS is an average wind on a hight of ten meters for the past ten minutes. The tower gives you the same but an average of two minutes.

[XCLTM3 112]

Thank you all for your input/advice...much appreciated!

 

Rgds,

 

Steve

[rcpistonhead 47]

How do you get the wind direction and wind speed to show up on the nav display under the GS/TAS? I have noticed that sometimes it is displayed but most of the time the wind info doesnt display at all... Not even blank values. Is there a setting in the fmc I am missing? Thank you!

[rsvit 16]

I have noticed that sometimes it is displayed but most of the time the wind info doesnt display at all...

 

Wind is insignicant or TAS is less then 101kt. See FCOM vol2, page 10.41.1 for details.