Why do aircraft tires have straight lines for treads? Why don't they have tread patterns as you see on a car tire? So they can land on wet or snowy runways. The tread allows the tire to make contact with the runway surface without hydroplaning so that the brakes on the landing gear can slow the plane down while maintaining control. Cars are driven by their wheels and wheels should be rotated periodically so the tread pattern is optimized for this.