Visible crew/equipment: When Father Mulcahy and the farmer are talking to BJ and Hawkeye about the wounded cow, the doctors say they'll get help from Colonel Potter, and when they walk away the T-mark can be seen on the ground where they were standing.
Plot hole: In this episode, Margaret is required to give a lecture on the use of Levophed, because it is being introduced. However, in the Episode "Period of Adjustment"(8-6), Hawkeye orders an IV of Levophed for one of his patients. (00:12:15)
Other mistake: When the scene is of the cow in the barn, the background hilly area can be a painted backdrop.
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.