In this case S N A F U come from “situation normal, all fu**ed up.”
即，SNAFU="situation normal, all fu**ed up"，（正常的情况全他妈乱了）。
2
On the left in this photo from 1992 is NASA research pilot Ed Schneider, who also flew NASA's B-52 mothership along with other planes including the F-15B aeronautical research aircraft.