Based on the maximum wing span and space between the outer main gears prescribed in the airport flight region grading index, airports are divided into _______ 5 grades.
A.1, 2, 3, 4, 5
B.A1, A2, A3, A4, A5
C.Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ
D.A, B, C, D, E
正确答案是D
Based on the maximum wing span and space between the outer main gears prescribed in the airport flight region grading index, airports are divided into _______ 5 grades.
A.1, 2, 3, 4, 5
B.A1, A2, A3, A4, A5
C.Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ
D.A, B, C, D, E
正确答案是D