飞越北极模型

Models for Flyiny over the Arctic Pole

本文采用过球面上两点与球心的平面和球体的交线作为飞行航线。模型一计算球体上大圆的劣弧长度得到了与问题结论相一致的结果，模型二计算椭球体上一椭圆的一段弧长得到了与问题结论较一致的结果。

In this essay,the flying route is the intersecting line which passes two points on the spherilal surface and the surface of the spherilal center and the spheroid. Model One deals with the length of the big circle's minor arc of the spheroid,and has achieved the same results as the problem discussed; Model Two deals with the elliptic arc length of the spheroid, and has achieved the appoximate results comparing to the problem discussed.