ACP 131(F) - https://web.archive.org/web/20130215140321/http://jcs.dtic.mil/j6/cceb/acps/acp131/ACP131F09.pdf Offered to NATO for adoption: https://archives.nato.int/uploads/r/null/1/2/127387/SGM-0921-55_ENG_PDP.pdf Was anyone actually expected to memorize all of these codes? 73, Andy, k3wyc