At 11:15 PST, a DeHavilland Tiger Moth DH 82A and a Cessna 152 collided on a taxiway at the Petaluma airport. Both aircraft sustained substantial damage but neither pilot was injured. The pilot of the Tiger Moth told investigators that he had just landed on runway 29 and had turned onto the taxiway. Approximately halfway down the taxiway his aircraft collided with the Cessna, which was being operated by a student pilot. The student pilot stated that he had attempted to raise the other pilot on the radio but received no response.