Durk Talsma wrote:
> I've seen this as well, but as far as I can tell, this is due to the
> wind blowing against the tail. I've seen this more stronger with heavy
> winds, and the yawing of the aircraft in heavy winds appears to change
> with changing rudder position, as I expected.
It's a misfeature in the gear modelling. YASim has pretty much the
same behavior. Both FDMs model gear force as a function of "skidding
velocity", which is fine for dynamic solutions. But a gear that is
planted on the ground is capable of "holding" an aircraft at zero
velocity, which doesn't work with the current FDMs -- zero velocity
produces zero force.
What's needed is code that, at low speeds, uses a spring model for
gear force based on the distance in position from where the gear is
"stopped". Which sounds easy, but in practice is awfully hard. I've
gotten started on this several times, and never produced useful
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