Principle of water-jet propeller operation is based on the increase of water flow in the jet. Change of the water flow creates reactive traction, providing movement of the ship. Control of the ship movement can be fulfilled by changing of speed and direction of the thrown out water stream.
Advantages:
1. Low fuel consumption, low level of noise, even at the full boat load top speed doesn’t lower practically, unlike, for example, outboard motors.
2. Simplicity in the use:ready to work instantly .
3. Wonderful navigability: a boat with water-jet propeller can turn around almost at one spot, it does not need maneuvering propulsion device, can turn around even above a fishing net.
4. A boat easily drives into trailer without engine turning off.
5. Low demands to maintenance: the amount of mobile and rubbing details is minimal. Operation life on condition of correct maintenance can be very long. Spare parts are supplied now for water-jets made even 30 years ago.
Useful properties of water jet show especially notably up at shallow water. Depth capability is determined only by boat draft in this case.

Mercury Jet 20
Two-cylinder two-stroke outboard motor with water jet propeller. Unique combination of compactness, small weight and easy assembling of the outboard motor and such valuable qualities of water-jet, as ability to work on minimum depths, absence of the external revolved parts (water-jet is more protected from breakages and is safe for bathers and water animals), possibility of turning around at the place. The hull of Mercury jet is made of stainless steel and flexible rotor provide high reliability of the jet and its stability to the deterioration. An engine has manual starting and tiller steering. The Modular CD ignition system provides sure starting and fuel economy, saving simplicity of service, high reliability and improved operating characteristics of engine at the same time. The cooling system is supplied with thermostat, optimal temperature condition of motor work is supported due to it. An engine is supplied with the long (558 mm) dead-wood and alternator of 76 watt power. The suspension bracket construction has 5 positions of tilt regulation.