Long Range — Page 35, Lesson 31

I want to walk you through a large set of standard aviation abbreviations and their meanings. These are the kind of shorthand codes you will see on flight plans, weather reports, NOTAMs, charts, and in radio communications. Let's go through them in the order they appear, defining each one clearly. Starting with "Long Range" — that's abbreviated LSQ. Then we have Line Squall, also abbreviated LSQ. A line squall is a narrow line of thunderstorms or strong winds along a cold front. Next, LTD stands for Limited. LTT is Landline Teletypewriter — that's an older ground-based teleprinter system used for sending written messages between aerodromes. LUT is Local User Terminal, which is a ground station that receives satellite-based distress signals, part of the COSPAS-SARSAT system. LV means Light and Variable, relating to wind — so when the wind is light and its direction is not steady. LVE is Leave or Leaving. LVL is Level, meaning a flight level or altitude. LVP stands for Low Visibility Procedures — these are special operating procedures at an aerodrome when visibility is below certain minima. LYR is Layer or Layered, used in weather reports to describe cloud layers. Now moving to the letter M. A single M followed by figures means Mach Number — the ratio of true airspeed to the speed of sound. A single M preceded by figures means Metres. So context tells you which one is being used. MAA is Maximum Authorized Altitude. MAG is Magnetic, as in magnetic heading or bearing. MAINT is Maintenance. MAP stands for Aeronautical Maps and Charts. MAPt is Missed Approach Point — the point on an instrument approach where you must execute a missed approach if you cannot see the runway. MAR can mean either At sea or the month March — again, context matters. MAS is Manual A1 Simplex — a type of radiotelegraphy mode. MATZ is Military Aerodrome Traffic Zone, the controlled airspace around a military airfield. MAX is Maximum. MAY is the month May. MB is Millibars, a unit of atmospheric pressure. MCA is Minimum Crossing Altitude — the lowest altitude at which you may cross a navigation fix when proceeding to another segment of an instrument procedure. MCW is Modulated Continuous Wave — a type of radio transmission where an audio tone modulates the carrier wave. MDA is Minimum Descent Altitude — the lowest altitude you may descend to on a non-precision approach without visual reference. MDF is Medium Frequency Direction Finding Station. MDH is Minimum Descent Height — similar to MDA but measured above the aerodrome elevation or threshold elevation. MEA is Minimum En route Altitude — the lowest altitude that provides adequate navigation signal reception and obstacle clearance on an airway. MEDA is Military Emergency Diversion Aerodrome. MVDF stands for Medium and Very High Frequency Direction Finding Stations at the same location. MEHT is Minimum Eye Height over Threshold, used for VASIS and PAPI visual approach slope indicator systems — it's the lowest height at which a pilot's eyes must be to see the correct light signals. MWARA is Major World Air Route Area — these are global regions used for organizing aeronautical radio communications. MET with a dagger symbol means Meteorological or Meteorology. METAR with a dagger is the Aviation routine weather report in aeronautical meteorological code. MF is Medium Frequency, specifically the band from 300 to 3000 kilohertz. MHDF is Medium and High Frequency Direction Finding Stations at the same location. MHVDF is Medium, High and Very High Frequency Direction Finding Stations at the same location. MHz is Megahertz, a unit of frequency. MID is Midpoint, related to RVR — that's Runway Visual Range, and the midpoint is the middle of the runway. MIFG is Shallow fog. MIL is Military. MIN is Minutes. MKR is Marker radio beacon — a ground-based transmitter that marks a specific point along an approach path. MLWA is Maximum Landing Weight Authorized. MLS with a double-dagger symbol is Microwave Landing System, a precision landing guidance system. MM is Middle Marker — the marker beacon located at the middle of an instrument landing system approach. MNM is Minimum. MNPS is Minimum Navigation Performance Specifications — the required navigation accuracy for operations in certain airspace like the North Atlantic. MNT is Monitor, Monitoring, or Monitored. MNTN is Maintain. MOA is Military Operating Area. MOC is Minimum Obstacle Clearance required — the minimum vertical clearance above obstacles in an airspace structure. MOD is Moderate, used to indicate the intensity of weather phenomena, interference, or static reports — for example, MOD RA means Moderate Rain. MOGAS is Motor Gasoline — automotive fuel, not aviation gasoline. MON can mean Above Mountains or the month Monday — context tells you which. MOTNE is Meteorological Operational Telecommunications Network Europe. MOV is Move, Moving, or Movement. MPH is Statute Miles Per Hour. MPS is Metres Per Second. MRA is Minimum Reception Altitude — the lowest altitude at which you can reliably receive a navigation signal. MRG is Medium Range. MRP is ATS/MET Reporting Point — a point where you must report your position to Air Traffic Services or for meteorological purposes. MS is Minus. MSA is Minimum Sector Altitude — the lowest altitude that provides at least 1000 feet obstacle clearance within a sector around a navigation aid. MSD is Minimum Separation Distance, used in military contexts. MSG is Message. MSL is Mean Sea Level — the reference datum for altitude measurements. MT is Mountain. MTOW is Maximum Take-off Weight. MTRA is Military Temporary Reserved Airspace. MTU is Metric Units. MTW is Mountain Waves — atmospheric waves caused by airflow over mountains. MTWA is Maximum Total Weight Authorized. MWO is Meteorological Watch Office. MX is Mixed type of ice formation, meaning both white and clear ice. Now moving to N. A single N means North or Northern latitude. A single N can also mean No distinct tendency in RVR during the previous 10 minutes. NAT is North Atlantic. NATFMS is National Air Traffic Flow Management System. NAV is Navigation. NB is Northbound. NBFR is Not Before. NC is No Change. NDB with a double-dagger symbol is Non-Directional Radio Beacon — a ground-based transmitter that emits a signal in all directions for navigation. NDS is Non-deviating Status. NE is North East. NEB is North Eastbound. NEG means No, Negative, Permission not granted, or That is not correct — used in radio communications to mean no. NGT is Night. NIL with asterisk and dagger means None or I have nothing to send you. NM is Nautical Miles. NML is Normal. NNE is North North East. NNW is North North West. And NOF is the start of the next section, which we will cover when we continue. These abbreviations are your professional vocabulary. You need to know them instantly, without thinking, because they appear on charts, in clearances, and in weather reports every single day.