What is the principle of hovercraft?

Hovercraft is a ship that uses the high-power fan on board to generate air higher than atmospheric pressure and press it into the bottom of the ship to form an air cushion with the water surface or the ground, so that all or most of the hull is out of the water surface and sails at high speed. According to the navigation state, hovercraft can be divided into full-lift hovercraft and sidewall hovercraft. 1959, Britain built the world's first full-lift hovercraft SRN 1. It set out from Calais, France, and successfully crossed the English Channel in 2 hours and 5 minutes. The appearance of hovercraft caused a sensation in the world.

Full cushion hovercraft is also called full floating hovercraft. This kind of boat is surrounded by a flexible apron made of nylon rubber cloth, and air is filled into the bottom of the boat through the lift fan of the door to form an air cushion, so that the whole boat floats on the "air cushion". The propulsion power of the full-cushion hovercraft is air propeller or jet propeller. This hovercraft not only has a speed of 50 ~ 70 knots, but also is amphibious and can cross obstacles and complex terrain. Moreover, its own magnetic field, water pressure field and sound field are very small, and its explosion-proof performance is also good. It is an ideal tool for carrying landing soldiers and anti-mines. However, when sailing in heavy waves, the stall is large and it is easy to produce side drift. At present, it is only used in the military to manufacture small ships, such as landing boats, minesweepers, missile boats, patrol boats and so on.