Simulating realistic sonar data is crucial for tuning detection and classification algorithms according to environment and acquisition characteristics. Moreover, robustness of performances estimation and prediction applications can be greatly enhanced as soon as such a simulation tool provides both a modular underwater world representation (multiple sensors, environments and acquisition conditions) and a selection of several computational engines (ray theory, parabolic equation …). Therefore, we developed such a framework for simulators, allowing both scene design and computational engine choice. Within it, a tube engine has been successfully implemented and realistic simulations obtained. Moreover, the engine keeps track of the full propagation history of the simulated acoustic wave allowing mission planning & debriefing to take benefit from this knowledge for environment assessment applications (mine hunting, for instance). Indeed, sea bottom regions non-observed during a survey (either planned or performed) can be computed, outlining areas of potential threats, for instance. Thus, bringing that non-statistical information to CAD/CAC systems may enhance the reliability of their outputs.