Escort Tug

Specialised tug attached by line to a laden tanker during pilotage, ready to brake or steer the assisted vessel if its main engine or steering gear fails. Escort tugs are typically 50–80 t bollard-pull tractor or ASD designs operating at speeds up to 10 knots in passive escort mode; in active escort the tug applies indirect-mode steering forces using its hull as a hydrofoil. OCIMF Escort Tug Guidelines define the procedures and the demonstrated steering and braking force requirements; many oil terminals require escort tug attendance for the final approach and departure.