回复：请自作聪明者不要把世人都当傻瓜: geosych orbit semiaxies is 42164 km.

"而飞机的飞行基本上与它到卫星的距离垂直" is absolutly wrong. It depends where that sat is. Say, if the SV is stationed above North America, the flight path of the MH370 could not be perpendicular to the SV. Don't bs if you don't know.