To study aircraft motion on ground,especially for an aircraft with multi struts and multi wheels,supplied a model of static friction which defined a friction force as a function of the elastic deformation of a wheel. The elastic deformation and its rate were computable. Then the model is a kind of dynamics models. Using the model, all components of friction force on every wheel can be calculated. By reckoning all friction forces into the motion equations,the simulation on ground could be achieved. The issue of static indeterminacy does not exist in the model. The model has been verified partly in a simulator. The simulating result was coincident with the analytical result. The model can be applied in simulating of aircraft motion on ground.