http://www.latimes.com/news/local/la...nes-california


After the crash, the state ordered Disneyland to retrain ride maintenance workers, managers and ride operators; to require a test run of all cars on Big Thunder Mountain before passengers are loaded; and to require that those who perform maintenance on rides be the ones who sign that the work was completed.

The Big Thunder Mountain crash was one of three major accidents during a five-year period at Disneyland in which ride maintenance arose as an issue. A patron was killed in 1998 when he was hit by an iron cleat that a taut rope tore from the Columbia sailing ship. Two years later, nine passengers were injured on Space Mountain when a bolt broke on a wheel assembly.

In 1997, Disneyland moved to a system of "reliability-centered maintenance," which relies on repair histories and failure rates rather than the intuition of experienced workers to determine how often a safety procedure needs to be performed.

A consultant hired by the park to plan the change estimated that Disneyland would save millions of dollars in maintenance costs. But longtime workers said that staffing and maintenance procedures were pared back and that redundancies that provided an extra margin of safety were eliminated. Numerous veteran ride mechanics and supervisors were laid off, fired or retired.