GPS/LNAV Issues

Hello everyone,

Just here to raise some of my concerns with the LNAV mode in most aircraft within IF. After flying quite a lot on IF recently, I have noticed that the Aircraft, when on LNAV mode, the aircraft constantly changes its heading to track direct to the Active waypoint, this is generally okay, in calm weather, but when you are faced with a substantial amount of wind from either side of the aircraft, the aircraft is blown of course by quite a distance, in todays case, it was 500m, you may think this isn’t a massive problem, but, for example, if you are following an airway, with multiple fixes/waypoints along this, even though the waypoints/fixes in the airway are all in a straight line, the aircraft will turn quite dramatically at each waypoint. Here is what I mean:

It gives this weaving effect, which shouldn’t be the case, shouldn’t the LNAV correct for drift and follow the Magenta line? Or am I missing something?

Thanks, Maksim.

Hey, do you have a repro flight plan for this? LNAV mode isn’t based on the DTK but on the XTRK distance. It may be possible that the wind pushes it too much off course if it’s too strong. What was the wind at the time?

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I’ll get that sorted for you :)

Edit: It was around 84kts, coming from the LH side of the Aircraft.

That was the entire FPL, I will try and do a repro with different winds.

I have done a YouTube video if this is okay, don’t know what happened to the quality, hope this explains it better.

Make sure you watch it in 1080p so you can see the X-Track reading in the bottom left.

@Laura

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