Photograph of airmail pilot Warren D. Williams
Warren D. Williams flew for the Post Office Department's airmail service from August 10, 1920 until August 29, 1927. He spent most of that time based in Cleveland, Ohio. On July 11, 1926, Williams was involved in the first airplane -to- airplane collision in the airmail service. He was flying de Havilland airplane #422 from Cleveland to Chicago, Illinois. While he was attempting to land, Williams collided with a small ship belonging to the Yakey Aircraft Company. The airplanes collided 30 feet in the air at the east end of the east-west runway. Fortunately neither pilot was seriously injured in the collision.
National Postal Museum, Curatorial Photographic Collection