- (1 airports)

A-A (44 airports)

B-B (77 airports)

C-C (68 airports)

D-D (34 airports)

E-E (16 airports)

F-F (27 airports)

G-G (34 airports)

H-H (32 airports)

I-I (10 airports)

J-J (15 airports)

K-K (30 airports)

L-L (56 airports)

M-M (63 airports)

N-N (32 airports)

O-O (16 airports)

P-P (54 airports)

Q-Q (3 airports)

R-R (27 airports)

S-S (81 airports)

T-T (36 airports)

U-U (3 airports)

V-V (14 airports)

W-W (26 airports)

Y-Y (6 airports)

Z-Z (1 airports)