Chaps,I have been waiting a long time to use the word "anomaly". I think it's pretty cool. Seems I have one of those with all my FMC enabled aircaft at the moment. I will be flying along, happy as Larry, clinging to the magenta line, singing my song, when all of a sudden the magenta line and all the waypoints will flip 90 degrees on my display and my aircraft will veer off. Checking the map in FS9 or FSNavigator shows I was originally travelling in the correct direction. So I try to use HDG mode to get back on course. Just as suddenly the magenta line and display will correct itself. Problem is, it's happening more and more, so I am weaving around the skies like a fool.Has anyone else experienced this?It's quite annoying.Cheers,Dave

if you are using FS's real-world weather my first reaction is you are experiencing FS's sudden wind/speed shifts that are throwing the aicraft off-course.FS, unless you are using a payware wind 'smoothing' program, will change direction of the wind as you change real-world weather zones.--

Scoob thanks but the aircraft is turning because of the magenta line and other data flipping. When this happens the aircraft turns into the erroneous heading. Nowt to do with wind mate.Dave