TM 1-1510-218-10 B-7 HR Hours HRZN Horizontal HSI Horizontal Situation Indicator HYD Hydraulic IAS Indicated Air Speed I/P Identification Of Position IC Intercom ICAO International Civil Aviation Organization IDENT Identification IDX Index IFF Identification, Friend Or Foe IFR Instrument Flight Rules IGN Ignition ILS Instrument Landing System IM Inner Marker IMC Instrument Meteorological Conditions IN Inch INBOUND CRS Inbound Holding Course INC Increment INCR Increase IND Indicator INF Information INSTR Instrument INTPH Interphone INTRPT Interrupt IOAT Indicated Outside Air Temperature IP Identification Pulse ITU International Telecommunications Union kHz Kilohertz KIAS Knots Indicated Airspeed L Left LB Pounds LC Local Time LDA Localize Directional Aid LDG Landing LEG DIST Leg Distance LH Left Hand LOC Localizer LONG Longitude LPM Liters Per Minute LSB Lower Sideband LT Light MAG Magnetic MAN Manual MAP Missed Approach Point MAX Maximum Mb Millibars MDA Minimum Descent Altitude MEM Memory MF Mandatory Frequency MFD Multifunction Display MHz Megahertz MIC Microphone MIN Minimum MKR Marker MM Middle Marker MNTR Monitor MPEL Maximum Permissible Exposure Level MPGS Mission Planning Ground Station MSA Minimum Safe Altitude MSG Message MSL Mean Sea Level N North NAV Navigation NAVAID Navigation Aid NDB Non-Directional  Beacon,  Navigation Database NM Nautical Miles NORM Normal NTPD Normal  Temperature  And  Pressure, Dry NX Next Waypoint OAT Outside Air Temperature