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mazelda

position trend vector problems

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Hi

looking for some advise on this as it is becoming a pain

when I fly pretty much any route for some reason at some point the position trend vector line will go to almost 180deg turn without any input from me whilst flying a flightplan.this causes the a/c to exceed bank angle with the associated warnings and invariabley an lnav and sometimes, autopilot dropout.

It does seem to occur when rex essential uploads latest weather although the trend will turn regardless of wind direction.

As I'm fairly new to the ngx I've not been putting wind speed and directions into the fmc plan I use fs commander for my flight plans and I have the latest registered fsuipc installed

any ideas?

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Hello ???

 

First of all, you must sign with your full real name in this forum.

 

Now on to the business; I don't know what do you use for weather (FSX default or addon) but the issue is most probably caused by violent changes in wind direction and/or speed. Weather depiction in FSX is notoriuously bad and quite unrealistic unfortunately.

 

The trend vector is the second derivative computation, and as such prediction, of the AC position as sensed by the inertial sensors (IRU/IRS). Even the slightest change of acceleration (aka wind gust) will be vectorially depicted in the observed direction. If you take an almost longitudinal wind gust it will show as a very sharp turn backwards.

 

If the amount and length of time the gust lasts is significant enaugh, it can pass the auto disconnection limits of various systems.

 

Hope this helps.

 

Ionut G. Micu

Romania

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Ionut, he wrote that he's using REX.

 

Mazelda, I'm sure some tweeking with you weather add-on will solve the problem. Maybe also check the REX-forum on similar issues.

I recommend installing the full (paying) version of FSUIPC. Solved every weather related issue for me (but then again I use ASE).

 

Good luck

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