In the case of a civil aircraftlighterthan air, the expression in flight relates to the period from the moment when it becomes detached from the surface until it becomes again attached thereto.
就轻于空气的民用航空器而言,飞行中是指自其离开地面时起至其重新着地时止。
2
Therefore, they will create sonic booms stronger and louder than those of smaller, lighteraircraft.