When a ship is sailing water’s stickiness causes resistance and water resistance is proportional to the area contact the water. So if we can use a thin layer of air film to separate ship from water and reduce the area contact to water we can reduce resistance sharply. But air bumped to the ship bottom usually cannot form an air film and resistance cannot be reduced.  

  Our technology is based on the air-film constant we discovered. We find out the law of air film forming at the ship bottom and invented the equipment that will forming a thin layer of air film at the ship bottom to reduce resistance. If our technology of forming a thin layer of air film at ship bottom is used, a 4200TEU container ship, for example, can save about 20% energy or save oil 7000t per year.

  Tests and researches show that when compared to hovercrafts, if lifting power of hovercrafts is considered, ships using our technology of forming a thin layer of air film at ship bottom to reduce resistance can save about 30% power and they are easier to maintain.Our technology can promote the speed of high-speed crafts by aobut 15%. Our equipments at the ship bottom will not inflence ship shape and they will only cause 1% more resistance. In addition, the engine of our ships can be lighter than oridnary ships and they can carry less oil, which are also very helpful in promoting speed. The building price of our ships is also lower than ordinary ships. Therefore, using ships that using a thin layer of air film at ship bottom to reduce resistance will bring great profits to ship owners.

 As early as in 1876 scientists found that water resistance to solids is 600 times greater than air resistance; so they suggested using a thin layer of air film to separate the ship body from water in order to reduce resistance. In the recent 100 years, scientists in many countries have tried to lubricate the ship with air. However, air inputted into ship bottom usually forms air bubbles instead of air films and the desired effects cannot be achieved. Although having encountered many difficulties, people have never give up researches on using air film to reduce resistance. After many experiments Cai jinqi discovered the rule of air film and invented the technology of forming a thin layer of air film at ship bottom, which solved the problem that had existed for 100 years and broke a new path for saving energy and promoting ship speed. When widely applied, this technology is sure to be very helpful to the development of the ship industry. This invention made China the first country in the world that solved the problem of forming a thin layer of air film at ship bottom and held the technology that could reduce ship resistance or promote ship speed obviously. The Chinese government appraised the invention as an excellent invention in 1993’s and it is the Shanghai high-tech project in 2004.