Glossary
Abbreviated briefing
A briefing used to update information previously received from an earlier briefing or from other sources.
Abeam
A position where an aircraft, object or fix is approximately 90 degrees to the left or right of an aircraft's track.
AGL
Above Ground Level. The altitude of the airplane above the terrain.
Airport Facility Directory
A publication listing information of operational importance about airports including communications data, navigation aids and special notices and procedures. Available in separate regional volumes.
AIM
Aeronautical Information Manual
AIRMET
Airmen's Meteorological Information
Angle of Attack
The angle between the relative wind and the chord line of the wing.
ATIS
Automatic terminal information service. A recording of current weather conditions at an airport.
AWOS
Automated Weather Observation System
Base Leg
Flight path at right angle to the landing runway off its approach end. Usually between thedownwind leg and the intersection of the extended runway center line.
Best Angle of Climb Speed (Vx)
Airspeed that results in maximum gain in altitude in a given time. This is the airspeed that will gain the maximum altitude in the minimum time.
Best Glide Speed
Airspeed that results in maximum glide distance.
Best rate of climb (Vy)
The airspeed that provides maximum increase in altitude with respect to time.
Carburetor heat
Provides a source of heated air to the carburetor intake to prevent or remove accumulation of carburetor ice.
CDI
course deviation indicator.
CFI
Certificated Flight Instructor
Common Traffic Advisory Frequency (CTAF)
The frequency designated for the purposes of airport advisory procedures when operating at an airport without an operating control tower. Pilots use the CTAF frequency to advise other pilots of their position and intentions when operating at airports with operating control towers.
Control Wheel
The device the pilot uses to move the ailerons and elevator. Sometimes known as the yoke.
Critical Angle of Attack
The angle of attack at which a stall will occur.
Crosswind
Flight path at right angle to the runway at departure end.
Dead reckoning
A navigation technique based on plotting courses and making calculations based on aircraft performance data and forecast winds aloft.
Density Altitude
Pressure altitude corrected for temperature. It is a measure of air density.
Designated Examiner
An individual designated by the FAA to conduct pilot certification practical tests.
Downwind Leg
Flight path parallel to the landing runway in opposite direction to landing. Wind is behind the airplane when flying downwind.
DUATS
Direct user access system that enables pilots to access weather data and file flight plans using a personal computer.
EFAS
En route flight advisory service is a service provided by flight service stations that provides current en route weather information and pilot reports. Also known as Flight Watch.
Elevator
The horizontal control surface on the tail of the airplane that controls pitch. By moving the control wheel forward or aft the pilot moves the elevator and hence lowers or raises the nose.
ETA
Estimated Time of Arrival.
FAR
Federal Aviation Regulations.
Final Approach
Flight path in the direction of landing along the extended runway centerline.
Flare
The gradual raising of the nose to bleed off airspeed and attain the touch down attitude just prior to touch down.
Flight Following
Consists of radar traffic advisories provided to VFR aircraft by air traffic control on a workload permitting basis. Although advice regarding proximity to other aircraft may be provided it is still the VFR pilot's responsibility to see and avoid other aircraft.
Flight Service Station
A facility which provides various services to pilots including weather briefings, flight plan administration and assistance in emergency situations.
Flight Watch
A service provided by flight service stations that provides current en route weather information and pilot reports. Also known as En route Flight Advisory Service (EFAS)
Go Around
An abandoned approach to land. Usually involves over flying the runway while initiating a climb to pattern altitude.
Ground Effect
A phenomena experienced when very close to the ground that produces a cushioning effect that allows the airplane to remain airborne at lower than normal speeds when at an altitude which is equivalent to less than the wing span of the airplane. Ground effect occurs as a result of the ground interfering with wingtip vortices and reducing downwash and induced drag.
Ground Speed
The speed of the airplane in relation to it's movement over the ground. Distance traveled divided by time.
Horizontal Situation Indicator (HSI)
An instrument which combines a directional gyro providing heading information and a VOR/ILS indicator.
ICAO
International Civil Aviation Organization.
ILS
A precision instrument approach system consisting of various electronic and visual aids including a localizer and glideslope.
Isogonic Line
A line on a chart connecting points of equal magnetic variation. KIAS Knots indicated airspeed.
KIAS
Knots Indicated Airspeed.
Leeward
region opposite the side from which the wind blows.
Magnetic Variation
the angle between true north and magnetic north as indicated on charts by isogonic lines.
Maximum glide speed
The airspeed that allows for the longest distance to be covered in a power off glide. Mode C
Altitude reporting mode for aircraft transponder.
Mode C
Altitude reporting mode for aircraft transponder.
MSL
Mean Sea Level. The average height of the surface of the sea from which elevations are referenced.
Nautical Mile
Distance of 6080 feet.
Normally Aspirated
Refers to piston engines that are not turbo charged.
NOTAM
Notice to airmen.. A notice containing information concerning the establishment, condition or change in any aeronautical facility, service, procedure or hazard, the timely knowledge of which is essential to personnel concerned with flight operations.
NTSB
National Transportation Safety Board.
OBS
Omnibearing selector. Also known as course selector.
Option
A clearance which authorizes a pilot to perform their choice of a full stop landing, touch and go, stop and go, low approach or go around/missed approach.
PAPI
Precision approach path indicator. A light system that provides visual glideslope indication using a single row of two or four light units.
Pilotage
A navigation technique that involves identifying outside visual reference points and comparing them with features described on charts.
Pitot Tube
A tube mounted on the outside of the airplane that is exposed to the relative wind and provides ram air pressure to the airspeed indicator.
Practical Test Standards
FAA publication that defines the tasks in which pilot competency must be demonstrated to pass a practical test.
Precession
Movement of a gyro in response to applied forces. Can be the cause of gyroscopic instrument errors.
Pressure Altitude
Is the indicated altitude on the altimeter with 29.92 inches of mercury set in the barometric scale window.
Progressive Taxi
Detailed taxi instructions provided in stages to a pilot who is unfamiliar with an airport.
PTS
Practical Test Standards are published by the FAA to define the tasks in which pilot competency must be demonstrated to pass a practical test.
Radar Vectors
A heading provided by air traffic control to provide navigational guidance by radar.
REIL
Runway end identifier lights. Two synchronized flashing lights, one on each side of threshold which identify the approach end of a particular runway.
SIGMET
Significant Meteorological Information
Squawk
Select a code or function using aircraft transponder.
Standard briefing
A pilot weather briefing containing the most complete available information regarding a proposed flight in a specific format.
TAS
True Airspeed is the speed of the airplane relative to the airmass through which it is moving.
Touch and Go
A landing immediately followed by a takeoff.
Traffic Pattern
The traffic flow prescribed for aircraft operations at an airport. Components of traffic pattern typically include upwind, crosswind, downwind and base legs plus final approach.
Tricycle Gear
Landing gear consisting of a nose wheel and two main wheels aft of the nosewheel.
UNICOM
Non-government communication facility which provides airport information at certain airports. May be used to request services such as refueling. In some cases the UNICOM frequency may also be designated as a common traffic advisory frequency.
Upwind Leg
Flight path in the direction of takeoff along the extended centerline. When upwind you are flying into the wind.
VASI
Visual approach slope indicator. A light system that provides visual glideslope indication using high intensity red and white light beams.
Vector
A heading provided by air traffic control to provide navigational guidance by radar.
Vertical Speed Indicator (VSI)
An instrument that indicates the airplane's rate of climb or descent.
Victor Airways
Airways based on VOR navigation aids. Depicted by blue lines on aeronautical charts and identified by a V (Victor) followed by the airway number.
Vr
Rotation speed at which nose is lifted during takeoff roll.
VOR
A ground based navigation aid that transmits very high frequency signals, 360 degrees in azimuth, oriented with respect to magnetic north.
Wind Correction Angle
The angle between the heading of the airplane and the course. Wind correction angle is used to offset tendency to drift off course due to effect of wind.
Windward
Region on the side from which the wind blows.
Yaw
Rotation of the airplane about the vertical axis.
Zulu Time
Coordinated universal time. The internationally used standard time for aviation purposes based on the time at 0 degrees longitude.