Aloft wind data in FMC

[Guest kohenen]

Hi, Anybody using the weather injection software like activesky can share how's the aloft wind data should be entered in the FMC so that fuel consumption or decend profile could be calculated more precisely. I have the aloft wind data for FL280, FL390 from these software but I cruise at FL330, do I just entered the figures for FL280 and FL390. How's the FMC figure out the wind data in FL330? Do the airline pilot get the updated aloft wind information for each waypoint in the FMC during the flight? Regards, Thomas

[tfm 169]

I asked this question a while ago on this forum or on the Level-D 767 forum. The answer seems to be that there is no way of doing this automatically, including when using flightplans built by FSBuild (which actually tells you the predicted winds aloft data at particular way points, a bit like Activesky X).I can't say how it's done in real life.Tim

[Guest FrancoisH]

I just asked a friend, flying on A320 for Air France, and he said on these plane there's no direct link between the FMGS and any external system that would allow automatic update of Wind datas.Then, they more likely set the wind, for medium and long range flight, before starting engines. So I don't know if MD-11 systems are working in the same way, anyway, you should know that real pilots do the same that you do, setting this manually ;)Regards.

[Guest kohenen]

Hi,A little clarification for my question. I am not concern about how the wind data is entered into the FMC automatically. I would like to know in real life/flight sim, do we enter the wind data for every waypoint before takeoff and on the way of the journey, do we get updated aloft wind data and manually entering it in FMC. Also, I am using active sky and it only gives the data in certain flight levels. e.g FL330 and FL290.. and I can see that wind directions and strenght are quite different. So if I cruise at FL310, how would the FMC calculated the predicted fuel consumption or decend profile.Regards,Thomas

[Guest j-mo]

I just average it out, and over the course of a long flight, it's pretty darn accurate, particularly on continental flights. Trans-oceanic, there aren't all the weather stations you need, so enter what you know. I do this before pushback to check that I have enough fuel for the trip. I add extra fuel for flights over the ocean to prevent a... ahem... situation before arriving at destination. You can monitor the wind indicator on your ND to check your data you've entered, too.If you run AS on a separate monitor, you could let it update winds during your flight. Then you can modify what's in your FMC.