Hi all. Question regarding entering winds on the legs/rte data page. Do you enter the wind dir/speed as seen on the ND or from the IRS display panel – as they differ which is the more accurate data to enter on this page?Or shouldnt you need to as this info from IRS is already used by the FMC for calculations?

Wind data for the route is supplied from the dispatcher in the real world, and usually received through ACARS.This information helps the crew more accurately predict fuel consumption throughout the flight.Inputting what you see on the ND won't do anything for you or the FMC.What you can do though is input the forecast winds aloft on the descent to help VNAV.US - http://aviationweath...ucts/nws/winds/Canada - http://www.flightpla...xt&TypeDoc=html

Edited March 1, 201214 yr by trip7cap

But i have noticed that when i enter the wind from ND or IRS the FMC does do some recalculating - obviously depending on head or tail wind it recalculates the ETA +/- few minutes. So it must do something in the FMC.

I use FS Build + AS2012 and put all the info in BEFORE I start the engines.

The value that's meant to be entered there is supposed to be the wind reported by an aviation weather service. If you have ActiveSky, its route analyzer can serve this purpose. To be honest, though, you can get similar precision by just entering the average wind/temp on the INIT REF page when you're setting the flight up.

Wind data is mainly for FMC to calculate performance data (ETA, fuel, etc), especially when you are performing a long-haul. I know that in real world the data is transmitted through ACARS datalink, but unfortunately in flight sim there is no datalink for you. I have FSBuild and Active Sky so FSBuild gives me a dispatch release including all ETA, fuel prediction, and wind dir/spd at each waypoint. Entering wind data into FMC is time-consuming and not necessary unless fuel is not enough (or you think it might not be enough). I have never tried to do it.