随着航空工程师发现了机翼后掠可以推迟激波的发生,从而提高飞机的高速飞行性能,人类的固定翼飞行器设计便进入了后掠翼时代。速度的提升也大大增加了飞机的动能,同时也意味着飞机坠落时产生的破坏力达到了空前的程度。人们不能不考虑那些翱翔在空中的“大鸟”会带来多么强大的破坏力,作为交通工具的民用客机原来也具有如此之大的威力,会对地面造成诸如9·11那样的恐怖! As aviation engineers discovered that swept-back wings could delay the onset of shock waves and thus improve the aircraft’s high-speed flight performance, the design of a human fixed-wing aircraft entered the era of swept-back wings. The speed increase also greatly increases the kinetic energy of the aircraft, but also means that the destructive power of the aircraft crashed reached an unprecedented level. People can not but consider the powerful destructive power of the so-called “big bird” flying in the air. Civilian airplanes as a means of transport originally had such great power that they would cause terrors such as September 11 to the ground !