Visible crew/equipment: When Colonel Potter surprises everybody with his "little Olympics" idea in the mess tent, after Margaret comments, "I just know I'm not going to have anything left for Donald," at the start of the next shot the boom mic casts a very quick moving shadow on BJ.
![M*A*S*H mistake picture](/images/screenshots/217000-217999/217642_sm.jpg)
Visible crew/equipment: While Colonel Potter has everyone gathered in the mess tent to surprise them with his "little Olympics" idea, the studio soundstage is visible at the top, left side of the screen.
Answer: It is actually Cencompac for Central Command of the Pacific. It is like the headquarters for all military activity in the Pacific Region (Japan, Korea, Okinawa, etc. The newer version of that is United States Pacific Command (USPACOM).
EMTurbo
And the abbreviations were used mainly by the Navy. Especially CENCOMPAC.
Https://en.wikipedia.org/wiki/United_States_Indo-Pacific_Command.