The Role of Simulation as an Integral Element of Risk Reduction for Autonomous Underwater Vehicle Operations

Autonomous underwater vehicles (AUVs) are enabling the collection of unique oceanographic data sets and are playing an increasingly important role in the exploration and monitoring of the global ocean. However, AUV operations inherently involve significant risk due to the complexity of the vehicles, the limited opportunities for operator intervention, as well as the dynamic and often poorly characterized environments in which they take place. To improve operational reliability, we present a practical approach for integrating high-fidelity simulation into the operational risk management workflow of long-range AUV campaigns. Using Autosub Long Range, an ultra-long-endurance AUV designed for over-the-horizon operations, we demonstrate how high-fidelity physics-informed simulation can be systematically employed to support mission rehearsal, software validation, navigation assessment, and contingency evaluation both before and during field operations. The approach is applied across three complex real-world campaigns: extended unaccompanied operations in the Southwest Approaches, low-altitude surveys near decommissioned oil and gas infrastructure in the North Sea, and multiday under-ice operations in the Amundsen Sea. The results indicate that high-fidelity simulation can play a significant role in reducing operational risk, improving mission preparedness, and increasing confidence in autonomous system behavior.