The Osan Terminal Control Area is an American run TCA part of the [[RKRR Incheon FIR]] that is composed of 2 joint South Korean-American air bases (RKSW and RKSO) and 1 Army Air Field (RKSG). Phraseology is all FAA phraseology per the US Order 7110.65. Please see the [http://www.ivaous.org/fdr/References/Standard%20Phraseology%20Guide.pdf XA Division's Guide to FAA Phraseology] to control this area. Please note that altimeter settings are given in inches (Altimeter 2992) and are given in the IVAC METAR and ATIS, so no conversion is necessary.