Consider a vessel that's essentially a floating engine. Beyond crew, it's not designed to take any passengers, nor is it equipped for cargo. Slow, but powerful, it features an extreme power to tonnage ratio, up to 10 times more than much larger vessels such as bulk carriers or cargo ships.
What is it?
The humble tugboat. They are the unsung heroes of the shipping industry. Without them, international trade grinds to a halt - no containerised imports or exports to stimulate the global economy.
A tugboat (or tug) is specifically designed to push or tow vessels that are either unable to move on their own, or cannot navigate restricted shipping routes (such as narrow canals or harbours). Commonly found in ports across the globe (both large and small), some tugboats are ocean-going and have even been used as icebreakers.
Though sizes vary between makes and models, a typical tugboat (found in most major ports across New Zealand or Australia), can measure 24 metres in length and about 11 metres wide. Equipped with azimuth thrusters (special propulsion technology that facilitates movement in any surface direction), it boasts a 6,000 horsepower engine that allows the tugboat to push or pull much larger ships, some exceeding 300 metres in length.