## RE: [Flightgear-flightmodel] engine and propeller data

 RE: [Flightgear-flightmodel] engine and propeller data From: Tony Peden - 2001-08-06 15:34:56 ```--- David Megginson wrote: > Jon S. Berndt writes: > > > > I'm curious about the transition. Let's say > that the gear code > > > becomes capable of holding the plane still on > the ground with a 4kt > > > crosswind. Once the plane starts rolling at, > say, 0.001kt, should the > > > wind suddenly start spinning it around and > sliding it sideways? > > > > There are some transition effects to consider > that are somewhat related. I > > am creating a diagram and short paper which > describes the problem a bit more > > clearly, I hope. That will give anyone interested > a starting point to > > consider, and the various intricacies can be > understood. > > I'm going to try to review my terminology a bit; is > this right? > > static friction: the resistence of the gear when the > plane is at rest. > > sliding friction: the resistence of the gear when > the plane is moving > in a direction other than the gear's direction of > rotation (or when > the brakes are applied). > > rolling friction: the resistence of the gear when > the plane is moving > in the direction of the gear's rotation and the > brakes are not > applied. > > Is this roughly right? If it is, I'm still confused > about some > things; for example, if the plane is rolling > directly east (no > sideways movement) and there is a 10 wind from the > north, what kind of > friction keeps the plane from sliding to the right? Static. The key here is that at the point of contact between the tire and the pavement, there is no relative motion between the two. > It doesn't seem > that sliding friction is right, since the plane is > not currently > moving in that direction (as it might be, for > example, if I landed in > an extreme crab), but I'm not sure that static > friction applies if the > plane is in motion in any direction. > > > All the best, > > > David > > -- > David Megginson > david@... > > > _______________________________________________ > Flightgear-flightmodel mailing list > Flightgear-flightmodel@... > http://lists.sourceforge.net/lists/listinfo/flightgear-flightmodel > > __________________________________________________ Do You Yahoo!? Make international calls for as low as \$.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/ ```