Fire Fighting Systems of Norway tested what it claims is the world’s largest water cannon (fire monitor) for maritime fire-fighting in December.
The fire monitor has a capacity of 70,000 liter/minute (18,500 U.S. gallon/minute) and is fully adjustable. It can deliver over one ton of water per second with a throw length up to 200 meters.
A fire monitor is a fixed, high-capacity water canon designed for fire-fighting purposes, though it also can be used against pirate attacks. Typically water cannons, installed on rescue boats, tugs and OSVs, can discharge water over tens of meters.
The jet of water is created in the monitor outlet by pressing water at optimum speed through a specially-designed monitor nozzle. The force generated must be compensated by the vessel propulsion and maneuvering system for station keeping.
Source: maritime-executive.com