If frost is not removed from the wings before flight, it may cause _______ .
A.an early airflow separation
B.decrease in lift and increase in drag
C.a stall at a lower-than-normal angle of attack
D.all the above
正确答案是D
If frost is not removed from the wings before flight, it may cause _______ .
A.an early airflow separation
B.decrease in lift and increase in drag
C.a stall at a lower-than-normal angle of attack
D.all the above
正确答案是D