Well, the single most unrealistic thing about taxiing is the traction on the wheels, or more specifically the lack of it.
What I mean is in reality the interaction between the tire and road is rather complex and, when the tire is pivoted away from its rolling direction there is an immediate and significant sideways force generated, and the forces is usually strong enough to keep the tire rolling straight on the road. In IL-2, you sort of just skid on top of the surface at the slightest slip angle of the wheels - there's no real traction. Turning nose wheel often has no visible change at all and you have to apply brakes to actually turn the aircraft.
Unfortunately this leads me to believe that the friction forces between wheel and ground surface is modeled in a very simplistic manner, most likely due to computational budget concerns. What that means is it isn't likely to be possible to modify to a more realistic direction. Of course, I could be wrong.
If someone wants to look into it, here are some useful links:
http://en.wikipedia.org/wiki/Cornering_forcehttp://en.wikipedia.org/wiki/Contact_patchhttp://en.wikipedia.org/wiki/Frictional_contact_mechanicshttp://en.wikipedia.org/wiki/Slip_(vehicle_dynamics)Basically what you would want is to increase the traction force (sideways force in relation to the tire's axle) at low slip angles. What that would do is make it harder for the tire to slip and slide on the surface, and instead the response of for example turning the nose wheel slightly would immediately start turning the aircraft's nose, while the tire would still seem to be rolling "straight" on the surface instead of sliding like it currently does.
Of course you would have to also simulate the breaking point of the traction, where the slip angle is increased so much that the traction force is lost and the tire really does begin to slide sideways on the surface.
I have no idea if these things would be feasible to add or modify to be more accurate in in IL-2. Mathematically speaking, the equations of cornering force, critical slip angle and kinetic friction are simple enough, but modeling the shifts between these forces would be quite hard.
Of course in addition to the actual steering forces, you would have to simulate the torque effects they would have on the plane - the centre of gravity is always above the landing gear contact patches, so when turning you would also apply roll torque toward the direction of the turn, and if the centripetal force from the landing gear contact patches is enough, you would lift the inner landing gear and, if you increased the yaw further you would roll the aircraft over. It seems that a rudimentary system to simulate this is already in the place.
The place to start looking for ways of modification would, then, be the friction values of the surfaces I think. In FMB there is a tick box to "enable friction" and a value that can be edited. The default value seems to provide default taxiing characteristics. I shall attempt to increase the friction and report back what happens.
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Topic: what about taxing? (Read 11442 times)
