The only problem is that it needs to be supremely accurate, since the margin for error on a curling shot is much smaller at altitude.
唯一的问题在于它需要无比的精确，因为在高海拔处曲球的犯错空间要小得多。
2
Analyses show that a measurement of 5 points altitude in the free flight path, the impact position error may be estimated probably.
分析表明，在自由飞行段5点测高可以估出落点偏差。
3
The working principle of the altitude maintenance system was introduced, the related mathematical models were built up, and the problem of static error of system was solved.