竹蜻蜓呈T字形,横的一片像螺旋桨,当中有一个小孔,其中插一根笔直的竹棍子(图1己),用两手搓转这一根竹棍子,竹蜻蜓便会旋转飞上天,当升力减弱时才落到地面。竹蜻蜓是中国古老儿童玩具。在18世纪传到欧洲,被称为“中国陀螺”。英国人乔治·凯利一辈子都对竹蜻蜓着迷。他的第一项航空研究就是在1796年仿制和改造了“竹蜻蜓”,并由此悟出螺旋桨的一 The bamboo poles are T-shaped, and the horizontal ones are like propellers. There is a small hole in it, in which a straight bamboo stick (Figure 1) has been inserted. By twisting this bamboo stick with both hands, the bamboo pole will spin and fly. When the lift is weakened, it falls to the ground. Penny is an ancient Chinese children’s toy. In the 18th century it was spread to Europe and it was called “China Top”. The British George Kelly has been fascinated by bamboo rafts for a lifetime. His first aeronautical research was to imitate and transform the “bamboo cricket” in 1796 and realize the propeller one by one.