Alcatraz Island, San Francisco, CA
Background: A tram used to transport tourist excursions of physically challenged patrons up to the prison itself on Alcatraz Island in San Francisco Bay struck a protruding pipe on a wall adjacent to its path of travel. The roof and super-structure of the tram trailer were damaged, and struck passengers on the tram. Subsequent to the accident, it was alleged that the design of the trailers was faulty. The pipe itself could not be removed because of the historical nature of Alcatraz Island and the prison.
What We Did: In reconstructing the accident, a 1/8-scale model of the trailer was created, complete with four-wheel steer capability, for purposes of visualization to Jury members. The model and a similar scale roadway model, as well as full-scale experiments with an undamaged tram, clearly demonstrated that the mechanics of the accident sequence involved the tram driver steering the tram into a gutter adjacent to the wall, and showed that there was no fault in the design of the trailers.