The Towed Torpedo Emulator (TOTEM) System

This article describes a new towed underwater acoustic projector system designed to exercise Naval surface ship torpedo detection systems. The TOTEM system is built around a standard 7-m Rigid-Hulled Inflatable Boat (RHIB), with capability for towing the acoustic projector towfish at depths up to 40 m and speeds up to 20 knots. The RHIB was modified with a more powerful (260 HP) engine, a twin-counter-rotating propeller drive, a hydraulic winch, and deployment/recovery A- frame. The acoustic projector systems were designed to broadcast torpedo-like signatures, contained in standard WAV files, over the frequency band 100 Hz to 10 kHz, with an additional 20- 32 kHz pinger emulating a torpedo sonar. An overview of the system design and results from recent sea-trials and acoustic calibrations will be given.