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All those acronyms in the aircraft cockpit
What does it all mean?
Long before "LOL" and "OMG" became everyday conversation for some, we in the aviation community adopted our own abbreviated lingo. As a new aircraft owner, learning a few key terms will get you started talking like a pro in the cockpit or the cabin. Here are some of the most common terms.
Who's Who
- ATC | Air Traffic Control
A service provided by the FAA to promote the safe, orderly and expeditious flow of air traffic
- AO | Aircraft Operator
Organizations and people who own or operate the equipment, procedures and information used to support the aircraft’s overall missions
- CFI | Certified Flight Instructor
A pilot who's certified by the FAA to offer aircraft instruction
- PIC | Pilot in Command
The pilot responsible for the control and operation of the aircraft during flight
- SIC | Second in Command
The pilot who is designated to take over control of an aircraft under direction of the pilot in command
- FBO | Fixed-Base Operator
Supplier of fuel, maintenance, flight training and other services at an airport
- FAA | Federal Aviation Administration
An agency of the U.S. Department of Transportation responsible for ensuring the safety of civil aviation
- FSS | Flight Service Station
Facilities that provide pilot briefings and routine en-route communications
- EFAS | En Route Flight Advisory Service
Technology that provides en route aircraft with flight updates and important weather alerts
- GA | General Aviation
The portion of civil aviation that refers to flights other than military, scheduled airline and cargo flights
Operational Abbreviations
- VFR | Visual Flight Rules
Guidelines governing flights flown solely by reference to visual cues
- IFR | Instrument Flight Rules
Guidelines governing flights under conditions in which it’s not safe to fly using only visual references
- VMC | Visual Meteorological Conditions
Weather conditions that allow for VFR
- IMC | Instrument Meteorological Conditions
Weather conditions that require IFR
- AVGAS | Aviation Gasoline
Piston aircraft fuel
- MEL | Minimum Equipment List
A list of instruments, equipment and procedures necessary to pilot a specific aircraft
- AIM | Aeronautical Information Manual
Official FAA guide to basic flight information and ATC procedures
- UNICOM | Universal Communication
A common radio frequency used at uncontrolled (non-tower) airports for local pilot communication
- METAR | Meteorological Aerodome Report
Weather conditions observed at an airport
- ATD | Actual Time of Departure
The time a pilot takes off from an airstrip or airport
- ETD | Estimated Time of Departure
The time a pilot plans to take off from an airstrip or airport
- ATA | Actual Time of Arrival
The time a pilot lands at a destination
- ETA | Estimated Time of Arrival
The time a pilot plans to land at a destination
- ATIS | Automated Terminal Information Service
Continuous broadcast of vital information including wind direction, velocity, pressure readings and active runway assignments
- AFM | Airplane Flight Manuals
Documents developed by the aircraft manufacturer and approved by the FAA, containing information and instructions required to operate the aircraft
- POH | Pilot's Operating Handbook
Document developed by the aircraft manufacturer containing the FAA-approved AFM
Instrumentation
- A/C | Aircraft
Refers to an aircraft, not air-conditioning
- ADI | Attitude Direction Indicator
An instrument that shows the aircraft's orientation relative to the horizon, shows the roll and pitch of the aircraft
- DME | Distance Measuring Equipment
An instrument that measures slant range distance from a nav aid
- ALT | Altimeter
An instrument that measures an aircraft's altitude
- HDG | Heading
The direction the aircraft's nose is pointing
- NAV | Navigation System
The aircraft's directional system
- GPS | Global Positioning System
Satellite-based navigation information
- VSI | Vertical Speed Indicator
An instrument that displays an aircraft's rate of climb or descent
- OAT | Outside Air Temperature Gauge
An instrument that displays the temperature of the air immediately outside the aircraft
- EHSI (or HSI) | Electronic Horizontal Situation Indicator
Combines a heading indicator instrument with course deviation indicator
- VOR | VHF Omnidirectional Range
Short-range, ground-based radio navigation system for aircraft
A Few Common In-Flight Terms
- CAS | Calibrated Airspeed
The indicated airspeed of an aircraft, corrected for position and instrument error
- IAS | Indicated Airspeed
A direct instrument reading not corrected for position and instrument error
- CAT | Clear Air Turbulence
Turbulent conditions absent of visual indicators such as clouds
- CAVU | Ceiling and Visibility Unlimited
Ideal flying weather
- AGL | Above Ground Level
Measurement of altitude above a specific land mass
- MSL | Mean Sea Level
The average height off the surface of the sea for all stages of tide
- ALS | Approach Light System
Lighting system on the approach end of the airport runway
- AGR | Air-Ground Ranging
Straight-line distance from the aircraft to a point on the ground