Abstract
A pebble, as small as it can be clipped in tire tread, could give a slight scratch on a windshield. The small damage could become an entire surface destruction by the progress of the crack. Sometimes, it occurs suddenly while car running and it will block up driver's view in a flash. This is very dangerous in road traffic. In this research, we analyzed the occurrence situation of the accidents which were given a damage on the windshield with a flying-pebble. And we investigated the pebbles (quantity, size, weight) which were clipped on tire of vehicles which were really used.
