The decision making task of ship damage control includes addressing problems such as fire spread, flooding, smoke, equipment failures, and personnel casualties. It is a challenging and highly stressful domain with a limited provision for real-life training. In response to this need, a multimedia interactive damage control simulator system, called DC-Train 2.0 was recently deployed at a Navy officer training school; it provides officers with an immersive environment for damage control training. This paper describes a component of the DC-Train 2.0 system that provides feedback to the user, called the automated instructor assistant. This assistant is based on a blackboard-based expert system called Minerva-DCA, which is capable of solving damage control scenarios at the "expert" level. Its innovative blackboard architecture facilitates various forms of user assistance, including interactive explanation, advising, and critiquing. In a large exercise involving approximately 500 ship crises scenarios, Minerva-DCA showed a 76% improvement over Navy officers by saving 89 more ships.