They could have just as easy used police phonetics:
Adam, Baker, Charles, David, Edward, etc...

Listed below are standard Police then Military phonetics for each letter.
A
Adam
Alpha

B
Boy
Bravo

C
Charles
Charlie (Cocoa)

D
David
Delta

E
Edward
Echo

F
Frank
Foxtrot(Fox)

G
George
Golf

H
Henry
Hotel

I
Ida
India

J
John
Juliette

K
King
Kilo

L
Lincoln
Lima

M
Mary
Mike

N
Nora
November

O
Ocean
Oscar

P
Paul
Papa

Q
Queen
Quebec

R
Robert
Romeo

S
Sam
Sierra

T
Tom
Tango

U
Union
Uniform

V
Victor
Victor

W
William
Whisky

X
X-Ray
X-Ray

Y
Young
Yankee

Z
Zebra
Zulu