Aviation milestone (4)
I believe the answer is:
solo
(Other definitions for solo that I've seen before include "On one's own, unaccompanied" , "By oneself" , "Unaccompanied flight" , "(Piece performed) on one's own" , "Fly aircraft" .)
I believe the answer is:
solo
(Other definitions for solo that I've seen before include "On one's own, unaccompanied" , "By oneself" , "Unaccompanied flight" , "(Piece performed) on one's own" , "Fly aircraft" .)