高于地面之航高
flying height above the ground
超过平均地面高度
height above average terrain
等高地面控制点
Ground control point with equal elevation
地面高程测量
terrian elevation measurement
地面高精度磁测
ground high-precision magnetic survey
high-accuracy ground magnetic survey
地面高精度磁法
High-precision ground magnetic survey
地面高速交通
high-speed ground transportation