The difficulties of authoring a formal notation from natural language to aid accident analysis

Much work has been carried out on using Petri Nets to describe interaction and the design of interactive systems. In this paper we are concerned with the use of Petri Nets to help describe accident scenarios. The issue here is that Petri Nets or some other formal notation might help eliminate ambiguities and imprecision that are characteristic of natural language descriptions in accident reports. We present a case study in which an attempt was made to describe a fragment of an aircraft accident report using a Petri Net description and identify four problems associated with this process. We argue that these problems can be overcome by the use of multiple renderings of the accident data. But this solution has its own problems of how to coordinate information from multiple renderings. A hypertext tool is outlined, which provides support for information coordination across multiple representations.