TM 1-1510-223-10 NAUT Nautical NAV Navigation NDB Non directional beacon NM Nautical miles NOC Navigation on course NORM Normal NP Navigation processor NTPD Normal temperature and pres- sure, dry NU Navigation unit OBI Omni bearing indicator OBS Omni bearing selector OM Outer marker OPER Operate PATT Pattern PB Pushbutton PC Programmable cartridge PIT Pitch PITCH SYNC Pitch synchronization PM Performance monitor POS Position PPC Performance planning card PRE Preset PREV Previous PROM Programmable  read-only memory PSI Pounds per square inch PSIG Pounds per square inch gage PVT Private PWR Power R Right RA, R/A Radio altimeter RAD ALT Radio altimeter RAM Random access memory R/C Rate of climb RCT Rain echo attenuation compensation technique RCV Receive RCVR Receiver REACT Rain echo attenuation compensation technique RG Rate gyroscope RH Right hand RMI Radio magnetic indicator ROL Roll RPM Revolutions per minute RT Receiver-transmitter R/T Rate of turn RTU Remote terminal unit RUD Rudder S South SA Surface to air SA/A-S Selective availability/anti- spoofing SAM Surface-to-air missile SAT Static air temperature SBY Standby SC Signal conditioner,  single channel SEC Seconds SEL Select SG Symbol generator SID Standard instrument departure SINCGARS Single channel ground and airborne radio system SPD Speed SQ Squelch SRN Short range navigation B-8