Accident Analysis of the Death Star (Part C1 – Ishikawa Analysis)Posted: March 2, 2012
Part C considers the circumstances of the accident up until the time of the explosion. Part D will consider the post-explosion response.
In Part C1 we apply the Kaoro Ishikawa method of analysis.
Ishikawa diagrams, also known as “fishbone diagrams” and “cause and effect diagrams” were invented byKaoro Ishikawa as a way of illustrating the way various factors causing a problem in quality control. They were adopted by Boeing Aerospace, first for quality control, then for analysis of accidents and incidents.
The strength of the technique is that it applies categories (traditionally the six Ms – Manpower, Methods, Machines, Materials, Measurements, Mother Nature) which result in considering a broader range of factors than would otherwise be thought about.
The main limitation of the technique is that causality is only loosely defined. In theory the method is based on “necessary and sufficient” causes, but in practice a wider range of influencing factors need to be considered. The method also struggles when people, methods and equipment are inter-related rather than being causally distinct.
In the diagram presented here, it is clear that the accident could be naively analysed as a technical design problem (an exposed reactor core), as human error (allowing a small band of plucky heroes within the protective shield), enemy action (the rebel attack) or poor safety process (failing to learn lessons from the first death star, and not considering whole-of-lifecycle risk).In fact, the accident was all of these things. The Ishikawa approach allows us to find a range of areas in which our organisation can be improved by learning from this accident.
One thing that the approach does not tell us is why this particular accident occurred. The features present in the accident were equally features of many Imperial operations. For example, a very similar diagram could be drawn for the Imperial attack on the Hoth Ice World, a near-complete success. On the one hand, this shows that careful analysis of past operations could cause organisational learning in time to prevent accidents such as the destruction of the Death Star. On the other hand, if the diagrams look the same for both events, we may have failed to consider important factors which caused the accident.