Noise Emission The noise emission inside of the passenger cabin is restricted to 65 db, like in a car. The noise emission outside of the craft results first of all from the propellers. To decrease that emission, the propulsion unit is equipped with nozzles. According to our current experience the noise level outside of propeller stream is not higher than for a fast boat. At low speed in displacement mode is not disturbing in a port. If there are special demands on very low noise level in displacement mode, the manoeuvring of the craft will be provided in using the water propulsion unit, which is arranged in the outer parts of both wings. It works almost without any noise.