Abstract: An underwater fuel transfer system for the transfer of liquid fuels such as crude oil from an off-shore underwater mooring to a submerged submarine oil tanker. There is provided a berthing guidance and control system including permanently moored acostic transponders interrogated by the tanker sonar equipment to provide input commands for azmith control along the on-tack position in conjunction with speed controls. The system also includes an arrestor mooring apparatus for decelerating the tanker as the tanker approaches the underwater station. This underwater station has the dual function use of providing mooring for the tanker and also reception of the tanker oil transfer device.