10 hours ago, strider1 said:

The weather-vaning doesn't effect landing, just takeoffs. And it's only the initial thrust, 0-40 knots at takeoff. And I think it's related to torque and the ground friction. But you are the expert !!!   

It's a separate effect from torque and propwash. You can see the weathervaning by setting up a 90 degree crosswind of just 5 kts from the left side, adding a little power to get the default Cessna moving (not takeoff power), and keeping feet off the rudder. The plane will slowly roll forward and gradually nose into the wind, steering off the runway to the left.

Change the wind direction so it's 90 degrees from the right side, do the same test, and the plane will gradually steer off the runway to the right side. Torque/propwash only works to one side, so this proves it's weathervaning from the wind. Increase the wind to 10 or 15 knots and the effect is even stronger. It will even happen with the Cirrus jet, which has no torque/propwash effect.

Ground friction may be involved, if there isn't enough tire friction against a sideways force like wind. It's still weathervaning, and I wish Austin would fix it.

10 hours ago, strider1 said:

Perfect, you get to practice your missed approach in the sim ! My personal minimums in real life are no lower then circle minimums and 3 statue miles of vis. Getting below the ceiling in real life is the goal not shooting minimums ! Thats Russian roulette.......  

Sure, but this isn't real life. 

Unless I'm testing a new plane model or something, almost all my sim flights are in the FSEconomy charter ops game, where a landing has to be made to get the $V for the assignment. So I'll adjust the weather if I have to, in order to stick the landing. Otherwise I've just wasted 2 hours of my time in the game. I don't like flying in blue skies all the time. I want enough challenge in the weather to make it interesting, but not impossible to fly. I don't think that's unreasonable.

Great OP and general discussions that follow.  I'm new to XP and only using out of the box stuff atm.  I do have x-camera and Head Shake as-ons tho.  From the latest dev Q&A, I think some of the things being discussed (not weather) will be addressed or an attempt to be addressed in the 11.1 update.  Nevertheless, I fly only GA and do enjoy my experiences with XP11.  Again, great thread!