This purportedly prevents separation and maintains airflow over the surface of the airfoil. The purpose of the step, it is claimed, is to allow some of the displaced air to fall into a pocket behind the step and become part of the airfoil shape as a trapped vortex or vortex attachment.
It can also be used with two steps on the top (KFm3), or two steps on the top and one on the bottom (KFm7). The two patents, US Patent # 3,706,430 and US Patent # 4,046,338, refer to the introduction of a step either on the bottom (KFm1) or on the top of an airfoil (KFm2), or both on top and bottom (KFm4).
The two men then filed for a patent on the stepped airfoil.įurther development resulted in two patents and a family of airfoils known as the KF airfoil and KFm airfoils (for Kline–Fogleman modified). He presented the paper airplane to Floyd Fogleman who saw it fly and resist stalling. After many experiments he was able to achieve this goal. In the early 1960s, Richard Kline wanted to make a paper airplane that could handle strong winds, climb high, level off by itself and then enter a long downwards glide.
0 kommentar(er)
