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Hirgab

Real-time weather wind shift

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Hi all,I have uploaded a video of strange behaviour that I witnessed yesterday when flying from OMDB to LIPZ. I was using ASE real-time weather. Notice the sudden shift of wind, is this normal? Also, notice the relationship between the speed tape and the wind direction on the navigation display. Is this normal behaviour? Can someone explain to me the aerodynamic behaviour of the plane when going through sudden wind shifts? I was flying the PMDG 747 if that matters at all.ps. Please don't mind the TV in the backgroundhttp://www.youtube.c...h?v=zBH5oUp-Nyk

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Hi all,I have uploaded a video of strange behaviour that I witnessed yesterday when flying from OMDB to LIPZ. I was using ASE real-time weather. Notice the sudden shift of wind, is this normal? Also, notice the relationship between the speed tape and the wind direction on the navigation display. Is this normal behaviour? Can someone explain to me the aerodynamic behaviour of the plane when going through sudden wind shifts? I was flying the PMDG 747 if that matters at all.
It's been discussed many times in the PMDG forum.The best thing to do is buy FSUIPC and use the wind smoothing options that it has. I used to get the same thing when flying naked with PMDG/LDS birds using ASE and no FSUIPC wind smoothing. After buying FSUIPC and using the suggested wind smoothing settings, I no longer get these eratic wind shifts using either DWC or Smooth Clouds in ASE.If you search it on the PMDG forum Ryan has posted the details of why the wind from ASE effects the a/c in the way it does if your interest in am in-depth explaination.I know you might not want to spend the $40 or so dollars on FSUIPC to get rid of the shifts, but in the end its worth the money considering everything else FSUIPC can do and the fact that there dont seem to be many alternatives to get rid of those wind shifts. BTW, you could try turing of the turbulence settings in ASE in the meantime to see if it helps a bit, but it wont fix it completely.POST EDIT: Here are some FSUIPC settings by Dan Downs you could try in this thread: http://forum.avsim.net/topic/333558-747-400x-and-the-weather/page__p__1967073__hl__wind+shifts__fromsearch__1#entry1967073POST EDIT 2; Here's the quote from Ryan explaining the why it does what it does.
Ok, here is the deal:We tried and this is not "fixable" - here is why (I'm paraphrasing from the explanation I got from Vangelis):The S-turns happen because of the way FS calculates forces being applied to the airplane while in ASE's DWC mode (any other weather addon doing what ASE does to modify the wind would cause the same thing). When the plane is LNAV (or NAV in the case of the MD-11), we calculate the lateral flightpath on the basis of track, which is true heading+wind correction angle. DWC mode imparts tons of tiny but sharp variations in the wind to control it - it's essentially "slapping" the airplane a bunch of times per second. This creates a force gradient (rate of change basically) that the autopilot senses as a change in the actual vs the target track. It tries to remedy this sensed difference with the ailerons, which produces the S turns and rolls. We cannot just filter this out because there are legitimate instances where the plane would need to respond to such a gradient that would look identical to what you see when in DWC mode.The only way to fly in DWC mode is going to be while using the standard FSX and FSUIPC tweaks to disable the turbulence effects on the airplane and setting the FSX rate of change slider to 25% - that stops the "slapping" effect and the forces on the airplane.

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cmpbellsjc, once again, THANK YOU!I appreciate the time it took for you to share your input.This seems like a common problem, FSUIPC is a bit pricey, might have to sleep on it today to decide on whether or not to shell out the money. Thanks again,Hirgab

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FSUIPC is an absoulte must-have in my opinion. Mostly for the wind smoothing, but also for other features like the autosave.

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FSUIPC is an absoulte must-have in my opinion. Mostly for the wind smoothing, but also for other features like the autosave.
+100 and if you use any hardware at all even a basic yoke/joystick + throttle the configurations it allows you to make are invaluable! I'd give up a lot of other add-ons long before it!

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Hi all,I have uploaded a video of strange behaviour that I witnessed yesterday when flying from OMDB to LIPZ. I was using ASE real-time weather. Notice the sudden shift of wind, is this normal? Also, notice the relationship between the speed tape and the wind direction on the navigation display. Is this normal behaviour? Can someone explain to me the aerodynamic behaviour of the plane when going through sudden wind shifts? I was flying the PMDG 747 if that matters at all.ps. Please don't mind the TV in the backgroundhttp://www.youtube.c...h?v=zBH5oUp-Nyk
I am using the FREE FSrealWX and it has options that allow you to tune down the wind shift problem. It it you can adjust the degrees per second and the knots per second as far as the wind in concerned. I could never use the winds aloft until trying this out. Here is a link to the site: FSrealWX LiteJim

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