Escort Tug

An escort tug is a high-performance tug that accompanies a laden tanker or other large ship through confined waters and provides emergency braking and steering force if the ship loses control, using its hull and propulsion to generate steering and retarding forces at speed. Escort tugs use tractor or azimuth stern-drive propulsion for the maneuverability the role demands, and are rated by the indirect-mode steering and braking force they can apply at a given speed.