In weather forecasts or pilot reports, aircraft structural icing is normally classified as _______ .
A.low, middle, and high
B.light, moderate, and heavy
C.low, moderate, strong, and severe
D.trace, light, moderate, and severe
正确答案是D
In weather forecasts or pilot reports, aircraft structural icing is normally classified as _______ .
A.low, middle, and high
B.light, moderate, and heavy
C.low, moderate, strong, and severe
D.trace, light, moderate, and severe
正确答案是D