Safety analysis techniques have traditionally been performed manually by the safety engineers. Since these analyses are based on an informal model of the system, it is unlikely that these analyses will be complete, consistent, arid error-free. Using precise formal models of the system as the basis of the analysis may help reduce errors and provide a more thorough analysis. Further, these models allow automated analysis, which may reduce the manual effort required. The process of creating system models suitable for safety analysis closely parallels the model-based development process that is increasingly used for critical system and software development. By leveraging the existing tools and techniques, we can create formal safety models using tools that are familiar to engineers and we can use the static analysis infrastructure available for these tools. This paper reports our initial experience in using model-based safety analysis on an example system taken from the ARP Safety Assessment guidelines document.