Aviation Glossary

An inspection required every 100 hours of flight time for aircraft used for hire...

The angle between the chord line of an airfoil and the relative wind. As AoA inc...

The ratio of wingspan to mean chord. High aspect ratio wings (long and narrow) p...

The cross-sectional shape of a wing, blade, or sail designed to produce aerodyna...

The tendency of an aircraft to yaw in the opposite direction of a roll input. Ca...

Hinged surfaces on the trailing edge of each wing near the wingtips that control...

Airmen Meteorological Information advisory for weather hazards significant to li...

The barometric pressure adjusted to sea level used to set the altimeter so it re...

The mass of air per unit volume, which decreases with altitude, increasing tempe...

A method of navigation that allows aircraft to fly any desired flight path witho...

The division of airspace into classes (A through G) with different rules for ent...

The highest level of pilot certification required for acting as pilot in command...

A surveillance technology where aircraft determine position via GPS and broadcas...

A gyroscopic flight instrument displaying the aircraft pitch and bank attitude r...

A barometric instrument measuring altitude by sensing atmospheric pressure chang...

An instrument measuring indicated airspeed by comparing pitot (dynamic plus stat...

An automated flight control system that maintains aircraft attitude, heading, al...

An airport designated in the flight plan where the aircraft can land if the inte...

An automatic landing performed by the autopilot without pilot manual control inp...

A small gas turbine engine in the aircraft tail that provides electrical power a...

A service provided by ground-based controllers directing aircraft movement in co...

An authorization by ATC for an aircraft to proceed under specified conditions. C...

A continuous broadcast of recorded airport information including weather, active...

A digital data link system for transmitting messages between aircraft and ground...

An ATC facility providing radar sequencing and separation services for arriving ...

The ATC facility providing separation services for IFR aircraft in the enroute p...

Medical conditions and physiological factors that affect pilot fitness to fly. T...

Over-reliance on automated systems leading to reduced pilot monitoring and degra...

Symptoms reportedly caused by exposure to contaminated bleed air from engine oil...

A systematic approach to mental processes used by pilots to determine the best c...

Airline Transport Pilot Certification Training Program required before taking th...

The condition of an aircraft being safe for flight, meeting all applicable certi...

A mandatory notice issued by the aviation authority requiring specific inspectio...

A comprehensive inspection required every 12 calendar months for aircraft operat...

An instrument displaying the current angle of attack relative to the critical an...

The runway length required to accelerate to V1 and then bring the aircraft to a ...

The maximum altitude at which an aircraft can maintain level flight. At the abso...

The tendency of the atmosphere to resist or enhance vertical motion. Stable air ...

The rate at which a parcel of air changes temperature as it rises or descends wi...

A structured verbal review of the planned approach procedure including minimums,...

The willingness and ability to speak up when safety is at risk, regardless of ra...

A downward angle of the wing from root to tip, opposite of dihedral. Used on som...

The indicated airspeed during the final approach segment. Typically Vref plus co...

A licensed professional who shares operational control responsibility with the p...

The technique of landing a helicopter without engine power by using the upward f...

Various lighting systems aiding pilots during night operations including runway ...

A configuration of signal lights extending outward from the runway threshold pro...

A gearbox driven by the engine that powers accessories including generators, hyd...

The unbalanced thrust condition in a multi-engine aircraft when one engine fails...

An automated system that adjusts engine power to maintain a selected airspeed, M...

A device that processes raw pitot-static and temperature data into calibrated fl...

A principle stating that as the velocity of a fluid increases, its static pressu...

The thin layer of air immediately adjacent to an aircraft surface where friction...

The airspeed that produces the greatest gain of altitude per unit of time. Used ...

The airspeed that produces the greatest altitude gain per unit of horizontal dis...

The ratio of air passing around the engine core to air passing through the core ...

Compressed air extracted from the engine compressor section used for cabin press...

A dangerous visual illusion during night approaches over water or unlit terrain ...

A collision between an aircraft and one or more birds. Bird strikes can cause en...

The runway length where the accelerate-stop distance equals the accelerate-go di...

The airspeed that maximizes the distance an aircraft can glide from a given alti...

The effectiveness of braking on a runway surface, reported as good, medium, poor...

Strategies to reduce bird strike risk including checking bird activity reports, ...

The point at which an aircraft would balance if suspended. CG position affects s...

The point on an airfoil where the total aerodynamic force is considered to act. ...

The straight-line distance from the leading edge to the trailing edge of an airf...

The curvature of an airfoil, specifically the asymmetry between the upper and lo...

The Mach number at which airflow over some part of the aircraft first reaches th...

Flight in which the ball in the slip-skid indicator is centered, meaning there i...

Effects that occur when air can no longer be treated as incompressible, typicall...

The wind component perpendicular to the runway direction. Pilots must know the d...

The height above ground level of the lowest broken or overcast cloud layer. Ceil...

Turbulence in cloud-free conditions, typically found near the jet stream and at ...

The thunderstorm cloud, extending vertically from low levels to the tropopause o...

The leading edge of an advancing cold air mass displacing warmer air. Cold front...

The vertical transport of heat and moisture in the atmosphere by rising air parc...

The intended direction of flight measured in degrees from north. The course may ...

Controlled airspace surrounding the busiest airports requiring ATC clearance for...

Controlled airspace around medium-traffic airports requiring two-way radio commu...

Controlled airspace around airports with an operating control tower. Requires tw...

Uncontrolled airspace where ATC does not exercise authority. Most common at low ...

A pilot license allowing the holder to be paid for flying. Requires at least 250...

A training methodology to improve aviation safety by optimizing the use of all a...

A needle showing lateral displacement from the desired course, whether VOR radia...

A landing technique used when wind is not aligned with the runway. Methods inclu...

A maneuver to align with a runway not served by a straight-in approach procedure...

An IFR approach requested by the pilot (never assigned by ATC) to proceed to the...

An accident where an airworthy aircraft is flown into terrain, water, or obstacl...

A disruption of normal airflow through the engine compressor causing a stall of ...

A propeller with a governor that automatically adjusts blade pitch to maintain a...

A device that mixes fuel with air for combustion in a piston engine. Carburetors...

Ice formation in the carburetor venturi and throttle body caused by fuel evapora...

A frequency designated for pilot self-announce of position and intentions at air...

A text-based communication system between ATC and pilots using data link instead...

An ATC position at towered airports responsible for issuing IFR clearances befor...

The ATC facility and frequency providing takeoff, landing, and traffic pattern s...

The body natural 24-hour biological clock that regulates sleep-wake cycles. Disr...

The tendency to search for or interpret information in a way that confirms pre-e...

The consistent and methodical use of checklists to verify that all required acti...

A pilot certificate authorizing the holder to give flight training and ground in...

A flight instructor certificate authorizing the holder to give instrument flight...

A precision approach with decision height between 100 and 200 feet and runway vi...

The lowest-minimum precision approach category. CAT IIIA: DH 100 feet, RVR 700 f...

A crash-protected device recording cockpit audio including crew conversations, r...

The engine whose failure would most adversely affect aircraft performance and ha...

A mode where engine igniters remain continuously energized to provide automatic ...

The fix, point, or route to which an aircraft is cleared by ATC. If the clearanc...

The ratio of height gained to horizontal distance traveled, expressed as a perce...

A runway with more than 25% of its surface covered by water, snow, slush, or ice...

An apparent force caused by the Earth rotation that deflects moving air to the r...

A systematic list of actions and checks performed during various phases of fligh...

A structured discussion between crew members before departure covering roles, ex...

The equivalent altitude representing the air pressure inside the pressurized cab...

A state of self-satisfaction and reduced vigilance that develops with routine an...

The window of circadian low between 0200 and 0600 local time when the human body...

A dangerous condition caused by inhaling odorless CO gas from exhaust leaks in p...

A flight plan combining IFR and VFR segments. The pilot files the IFR portion th...

The aerodynamic force opposing the motion of an aircraft through the air. Drag h...

The upward angle of an aircraft wing from root to tip when viewed from the front...

An oscillatory motion combining yaw and roll, common in swept-wing aircraft with...

The downward deflection of air behind a lifting surface. Downwash reduces the ef...

Pressure altitude corrected for non-standard temperature. It represents the alti...

The temperature at which air becomes saturated and moisture begins to condense. ...

The process of removing ice, snow, or frost from aircraft surfaces before takeof...

A radio navigation system that measures the slant range distance between an airc...

A navigation method of estimating current position by advancing a known position...

Regulations limiting the number of hours a pilot can fly and requiring minimum r...

The height during a precision approach at which the pilot must decide to land or...

The traffic pattern leg flown parallel to the runway in the opposite direction o...

A takeoff using less than maximum engine thrust to reduce engine wear, noise, an...

A condition caused by dissolved nitrogen forming bubbles in the body during rapi...

GPS navigation in a straight line from the current position to a selected waypoi...

A curved instrument approach segment flown at a constant DME distance from a VOR...

A threshold that is not at the beginning of the full-strength runway pavement. T...

A controlled emergency landing on water. Proper technique involves landing paral...

The process of determining density altitude from pressure altitude and temperatu...

The response of an aircraft over time following a disturbance. An aircraft may o...

Uncontrolled explosive combustion in a piston engine cylinder caused by excessiv...

FAR 91.17 prohibits acting as a crewmember within 8 hours of consuming alcohol, ...

A digital communication system between aircraft and ground stations for transmit...

The movable surface on the horizontal stabilizer that controls pitch. Deflecting...

The maximum time an aircraft can remain airborne with a given fuel load. Maximum...

Regulatory framework allowing twin-engine aircraft to fly routes beyond 60 minut...

The European Union agency responsible for civil aviation safety regulation. EASA...

An advanced GPWS using a worldwide terrain database and GPS position to provide ...

A gauge measuring the temperature of exhaust gases leaving the engine. EGT is us...

A diversion to a suitable airport during extended twin-engine operations due to ...

A rapid descent procedure used in the event of rapid decompression or smoke and ...

The rapid deplaning of all occupants from an aircraft due to fire, structural da...

The ratio of turbine discharge pressure to compressor inlet pressure, used as a ...

An integrated engine and systems monitoring display used in Boeing and other air...

The Airbus equivalent of EICAS, providing engine data, system synoptics, and che...

An infrared camera system that displays an enhanced image of the terrain and run...

An altimeter that provides digitized altitude information to the transponder for...

The partial or complete loss of engine power during flight. Single-engine proced...

Flight procedures with one engine inoperative in a multi-engine aircraft. Critic...

A complete disassembly, inspection, repair, and reassembly of an engine at manuf...

A series of events or errors that combine to cause an accident. Breaking any sin...

A device that transmits a distress signal on 121.5 MHz and 406 MHz upon impact o...

A hinged surface on the trailing edge of the wing that increases both lift and d...

A component of parasite drag caused by the shape of an aircraft creating pressur...

Rain that freezes on contact with surfaces at or below 0 degrees Celsius. Create...

A cloud at ground level that reduces visibility below 1 kilometer. Types include...

The boundary between two different air masses. Cold fronts bring rapid weather c...

The altitude in the atmosphere where the temperature first drops to 0 degrees Ce...

A standard pressure altitude expressed in hundreds of feet with the altimeter se...

The rules and regulations governing aviation in the United States, found in Titl...

A review required every 24 calendar months to maintain pilot privileges. Include...

The US government agency responsible for regulating civil aviation, including pi...

A computer system managing navigation, performance, and flight planning. The FMS...

A display system showing command bars on the attitude indicator that guide the p...

An instrument showing the rate of fuel consumption in gallons per hour or pounds...

The process of calculating required fuel for a flight including taxi, trip, cont...

A computerized system that manages all aspects of engine performance. FADEC auto...

Loss of combustion in a jet engine resulting in engine shutdown. Can be caused b...

Rotating propeller blades to a nearly streamlined position (edge into the wind) ...

A fuel delivery system that meters fuel directly into the cylinder intake port o...

A state of physical or mental exhaustion that degrades pilot performance. Fatigu...

A geographical position determined by visual reference, by one or more radio nav...

A document filed with ATC containing intended flight details including route, al...

A crash-protected device that records aircraft parameters including altitude, ai...

Damage to aircraft engines or components caused by ingestion of foreign objects ...

An assumed temperature higher than actual used to derate engine takeoff thrust. ...

A flight for the purpose of repositioning an aircraft or delivering it to a new ...

The pitch-up maneuver performed just before touchdown to reduce the rate of desc...

A dangerous aeroelastic oscillation of a control surface or structure that can r...

A cockpit control that selects which fuel tank feeds the engine. Proper fuel man...

Engine stoppage due to interruption of fuel supply despite adequate fuel remaini...

A flight control system using electronic signals to transmit pilot inputs to con...

A fly-by-wire feature that prevents the pilot from exceeding structural or aerod...

The intentional jettison of fuel in flight to reduce aircraft weight to maximum ...

A condition of increased lift and decreased drag experienced when flying close t...

The ratio of horizontal distance traveled to altitude lost in unpowered flight. ...

The vertical guidance component of an ILS providing a descent path typically set...

A satellite-based navigation system providing precise three-dimensional position...

The actual speed of the aircraft over the ground, determined by true airspeed mo...

The shortest distance between two points on the surface of a sphere. Long-haul f...

A cockpit featuring electronic flight displays (LCD or LED) replacing traditiona...

A system that alerts pilots to potential controlled flight into terrain by monit...

The procedure of abandoning an approach or landing attempt and climbing away for...

The international emergency frequency 121.5 MHz that all ATC facilities and many...

The ATC position controlling aircraft and vehicle movement on airport taxiways a...

A deadly vestibular illusion where a pilot in a gradual bank does not sense the ...

Loss of consciousness caused by excessive positive G forces reducing blood flow ...

A property of spinning bodies where an applied force is felt 90 degrees later in...

An accelerometer measuring load factor in G units. Shows current, maximum positi...

The wind component parallel to and opposing the aircraft direction. Headwinds re...

Ice balls or irregular ice formed in thunderstorms by strong updrafts cycling wa...

A gyroscopic instrument showing aircraft magnetic heading without the oscillatio...

A navigation instrument combining a heading indicator with VOR/ILS course deviat...

A racetrack-shaped flight path used to delay an aircraft at a specific fix. Stan...

An engine start where ITT or EGT exceeds the allowable limit, indicating insuffi...

The transfer of radar identification and communication responsibility from one A...

A condition of insufficient oxygen reaching body tissues, causing impaired judgm...

A condition of excessive breathing rate that reduces blood carbon dioxide levels...

Five dangerous pilot attitudes identified in aeronautical decision making: anti-...

One of three procedures (direct, parallel, or teardrop) used to enter a holding ...

A transparent display projecting flight data onto the windscreen, allowing pilot...

An engine start where the engine lights off but does not accelerate to idle RPM....

ATC clearance specifying the holding fix, direction of holding (relative to fix)...

A condition where a layer of water separates the tire from the runway surface, e...

A flight time recording device measuring elapsed time from engine start or weigh...

A long-range radio communication system using frequencies between 2 and 30 MHz f...

Drag created as a byproduct of lift generation, caused by wingtip vortices defle...

The accumulation of ice on aircraft surfaces when flying through visible moistur...

A model atmosphere used for aircraft performance calculations. At sea level: 15 ...

A precision approach system providing lateral guidance via the localizer and ver...

The airspeed shown on the cockpit airspeed indicator, derived from pitot and sta...

Flight rules requiring navigation solely by reference to flight instruments. IFR...

A qualification added to a pilot license allowing flight under IFR in instrument...

A check required for instrument-rated pilots who have not met instrument currenc...

The United Nations specialized agency that sets international standards and reco...

A series of predetermined maneuvers using flight instruments to guide an aircraf...

Temperature measured between the high-pressure and low-pressure turbine stages. ...

A point defined by the crossing of two VOR radials, a VOR radial and a DME dista...

The systematic cross-check of flight instruments during instrument flight. The r...

A takeoff initiated from an intersection of a taxiway and runway rather than fro...

A self-contained navigation system using accelerometers and gyroscopes to calcul...

A narrow band of strong winds (typically 100-200 knots) found at high altitudes ...

High-altitude airways from 18000 feet to FL450 defined by VOR radials. Designate...

A drainage wind caused by cold dense air flowing downhill under gravity, particu...

The aerodynamic force perpendicular to the relative wind generated by an airfoil...

The ratio of total lift to aircraft weight, expressed in G units. In straight an...

The horizontal distance required from 50 feet above the runway threshold to a co...

The lateral guidance component of an ILS providing precise runway centerline ali...

Localizer Performance with Vertical Guidance approach using WAAS GPS providing p...

GPS-based lateral guidance for non-precision approaches. LNAV approaches use a m...

Operations where a pilot is cleared to land and hold short of an intersecting ru...

A nighttime wind blowing from land to sea caused by the land cooling faster than...

A lens-shaped cloud formed in mountain wave crests. Lenticular clouds remain sta...

An ATC instruction authorizing an aircraft to taxi onto the runway and hold in t...

Four forces that cause a single-engine propeller aircraft to yaw or roll left: t...

Visual signals using a directional light from the control tower to communicate w...

The ratio of true airspeed to the local speed of sound. Mach 1.0 is the speed of...

The maximum speed at which full control deflection will not cause structural dam...

The maximum certified weight at which an aircraft is allowed to attempt takeoff....

Meteorological Terminal Air Report, a standardized format for reporting current ...

A small-scale intense downdraft that produces damaging divergent winds at the su...

A standing atmospheric wave generated when stable air flows over a mountain rang...

The angular difference between true north and magnetic north at a given location...

The direction the aircraft nose points relative to magnetic north. Magnetic head...

A certificate issued by an Aviation Medical Examiner attesting to pilot fitness....

A document approved by the aviation authority listing equipment that may be inop...

The most basic navigation instrument, using a magnetized card to indicate magnet...

An electronic display showing navigation, weather, engine, traffic, and terrain ...

A gauge measuring the air pressure in the engine intake manifold of a piston eng...

The lowest altitude to which descent is authorized during a non-precision approa...

A procedure executed when an instrument approach cannot be completed to a landin...

A cockpit control that adjusts the fuel-to-air ratio in piston engines. The mixt...

A self-contained electrical generator on a piston engine providing spark to the ...

The international distress call indicating an aircraft is in grave and imminent ...

Nausea and discomfort caused by conflicting motion sensory inputs from the eyes,...

The lowest altitude providing at least 1000 feet of obstacle clearance within a ...

The lowest altitude on a federal airway that ensures adequate navigation signal ...

The lowest altitude on an airway that provides required obstacle clearance. Navi...

An additional rating on a pilot certificate authorizing the operation of multi-e...

Radio beacons on the ILS approach path providing range information. Outer marker...

A pilot advisory to ATC indicating that any undue delay will result in an emerge...

A nose-down pitching tendency that occurs when shock waves on the wing move the ...

The lowest altitude at which ATC may issue radar vectors providing 1000 feet (20...

A ground-based radio transmitter that broadcasts on low/medium frequencies used ...

A notice containing information essential to flight safety not sufficiently know...

The rotational speed of the low-pressure compressor and fan in a turbofan engine...

The rotational speed of the high-pressure compressor in a turbofan engine, expre...

A standardized set of words representing each letter of the alphabet used in avi...

The tendency to underestimate the probability and impact of a disaster or emerge...

Permanent hearing damage from prolonged exposure to high noise levels in the coc...

To carry passengers at night, a pilot must have made at least three takeoffs and...

An instrument approach with lateral guidance but no electronic glidepath. VOR, N...

A thick grey cloud layer producing steady continuous precipitation over a wide a...

The process by which the eyes adapt to low light conditions using rod cells inst...

Specific departure and arrival procedures designed to minimize aircraft noise ov...

The upward forcing of air when wind encounters mountain terrain. This mechanical...

The pressure of oil in the engine lubrication system. Low oil pressure is a seri...

The weight of the aircraft including crew, fluids, and standard equipment but ex...

Mandatory and voluntary reporting of safety events including incidents, accident...

A landing at a weight exceeding the maximum certificated landing weight. May be ...

Drag not associated with lift production, including form drag from the aircraft ...

Asymmetric propeller thrust that causes yaw, most noticeable at high power and h...

Rotation of the aircraft about its lateral axis, controlled by the elevator or s...

The indicated altitude when the altimeter is set to 29.92 inHg (1013.25 hPa). Us...

An area of relatively high or low atmospheric pressure. High pressure systems br...

A weather observation made by a pilot during flight, reporting actual conditions...

Navigation by visual reference to landmarks on the ground such as rivers, highwa...

FAR Part 91 covers general operating and flight rules applicable to all civil ai...

FAR Part 121 governs scheduled air carrier operations with high safety standards...

FAR Part 135 covers commuter and on-demand air carrier operations. It has strict...

The first pilot certificate allowing a pilot to fly as pilot in command of an ai...

An ICAO framework replacing sensor-specific navigation requirements with perform...

A forward-facing tube that measures dynamic pressure (ram air) used to calculate...

An electronic display combining attitude, airspeed, altitude, vertical speed, he...

The procedure of moving an aircraft backward from its gate position using a tug ...

A reciprocating internal combustion engine driving a propeller for aircraft prop...

A rotating airfoil that converts engine power into thrust. Propellers can be fix...

The international urgency call indicating a condition concerning the safety of t...

The tendency to continue with the original plan despite changing conditions that...

The person who has final authority and responsibility for the operation and safe...

An instrument approach with both lateral and vertical electronic guidance to the...

A visual aid of four light units beside the runway showing the aircraft position...

The combination of throttle position and propeller RPM (piston) or N1/EPR (turbi...

A radio call reporting aircraft position, altitude, and intentions. Mandatory at...

Airport lighting activated by radio transmissions on the CTAF frequency. Typical...

The useful load that generates revenue, including passengers, baggage, and cargo...

A visual and tactile examination of the aircraft before each flight to verify ai...

The process of maintaining cabin altitude at a comfortable level while the aircr...

A sudden physical or mental inability of a pilot to perform duties. Can be subtl...

A long-period oscillation of aircraft pitch and altitude at essentially constant...

Step-by-step taxi instructions from ground control given one turn at a time for ...

Ignition of the fuel-air charge before the spark plug fires, caused by a hot spo...

A course reversal maneuver used to establish an aircraft on an inbound approach ...

The direction of airflow relative to the aircraft, which is equal and opposite t...

Rotation of the aircraft about its longitudinal axis, controlled by the ailerons...

The movable surface on the vertical stabilizer that controls yaw. The rudder is ...

The maximum distance an aircraft can fly with a given fuel load without refuelin...

The range over which the pilot of an aircraft on the runway centerline can see t...

The ratio of actual water vapor in the air to the maximum amount it could hold a...

A specification for RNAV systems that includes onboard monitoring and alerting c...

A magnetic bearing extending outward from a VOR station. Radials are named by th...

The reduction of vertical separation from 2000 to 1000 feet between FL290 and FL...

An instrument that measures exact height above the ground using radar signals. A...

The decision to abort a takeoff and bring the aircraft to a stop on the remainin...

Any occurrence at an airport involving the incorrect presence of an aircraft, ve...

The pilot repetition of an ATC clearance or instruction to confirm correct recep...

The specific radio channel used for communication between aircraft and ATC or ot...

Headings assigned by ATC to guide aircraft for traffic separation, sequencing, o...

The vertical speed of an aircraft in feet per minute during climb. Depends on ex...

The moment during takeoff when the pilot applies back pressure on the controls t...

Sudden loss of cabin pressure due to structural failure or door seal breach at a...

Rules determining which aircraft has priority in various situations. Aircraft in...

An unannounced FAA inspection of aircraft documents and pilot certificates durin...

A helicopter flight condition where the retreating rotor blade stalls because th...

Painted markings on runway surfaces including threshold markings, centerline, to...

A pair of synchronized flashing strobe lights located at the runway threshold to...

A gear mechanism that reduces propeller RPM relative to engine RPM for optimal p...

An aerodynamic condition where the critical angle of attack is exceeded and the ...

The minimum speed at which an aircraft can maintain level flight at a given weig...

An aggravated stall where the aircraft autorotates about its vertical axis while...

The procedure to recover from a spin, typically involving: power idle, ailerons ...

A movable panel on the leading edge of the wing that extends to increase the win...

A flat plate that rises from the upper wing surface to disrupt airflow and reduc...

The tendency of an aircraft to return to its original flight condition after a d...

An uncoordinated flight condition where the aircraft moves sideways toward the i...

A wing design where the leading edge is angled backward, delaying the onset of c...

The altitude at which the aircraft can no longer climb at more than 100 feet per...

The fuel flow rate divided by thrust or power output, measuring engine efficienc...

Significant Meteorological Information advisory issued for hazardous weather phe...

A local wind blowing from the sea toward land during daytime, caused by differen...

A narrow band of active thunderstorms forming along or ahead of a cold front. Sq...

A four-digit octal code set on the aircraft transponder for ATC identification. ...

FAR 121.542 requiring crew members to refrain from non-essential activities duri...

An ATC authorization for VFR aircraft to operate within surface-based controlled...

An opening in the aircraft skin that senses ambient atmospheric pressure for the...

An approach where the aircraft is in the proper landing configuration, on the co...

A precision landing technique to achieve minimum landing distance. Requires a st...

A takeoff technique for grass, dirt, or snow-covered surfaces that minimizes nos...

A published departure procedure providing obstacle clearance and noise abatement...

A published arrival procedure routing traffic from the enroute environment to an...

A system that alerts a specific aircraft crew when ATC needs to communicate over...

A pilot mental model of what is happening around the aircraft, including positio...

The inability to correctly determine aircraft attitude or motion relative to the...

A vestibular illusion during rapid acceleration (like takeoff) where the pilot s...

A physiological response to an unexpected event causing a brief period of confus...

Techniques for managing acute and chronic stress that affects pilot performance....

The initial pilot certificate required before a student can solo an aircraft. Mu...

A flight in which a student pilot is the sole occupant of the aircraft. Requires...

A pilot who is designated to be second in command during flight. Also called Fir...

A system that alerts the pilot to an impending stall through an aural warning (h...

A computer-generated three-dimensional display of the external terrain based on ...

Water droplets that remain liquid below 0 degrees Celsius. Contact with an aircr...

Low-level lumpy grey cloud layer common in marine environments. May produce ligh...

Flight control surfaces or devices deployed to increase drag and reduce speed wi...

Additional oxygen provided to crew and passengers when cabin altitude exceeds sa...

James Reason accident causation model where multiple defensive layers (like slic...

The initial tendency of an aircraft to return toward its original condition afte...

A rapid pitch oscillation at constant speed involving rapid changes in angle of ...

The angle between the aircraft longitudinal axis and the relative wind in the ya...

A thin region of extremely rapid pressure and temperature increase that forms wh...

The maximum loads an aircraft structure is designed to withstand. Normal categor...

A specific departure time assigned to an aircraft by ATC flow control to manage ...

The principle requiring pilots to maintain vigilance to see and avoid other airc...

A formal top-down organizational approach to managing safety risk. SMS includes ...

Also called vortex ring state, a dangerous helicopter condition where the aircra...

The emergency transponder code set when declaring an emergency. Squawking 7700 t...

The transponder code indicating communication failure. When a pilot loses radio ...

Backup flight instruments providing essential data when primary systems fail. Ty...

A computer-generated three-dimensional terrain display on the primary flight dis...

Aircraft communication via satellite providing voice and data connectivity over ...

The reaction force to propeller rotation that tends to roll the aircraft in the ...

Adjustable surfaces or tabs that allow the pilot to relieve control pressure for...

The horizontal distance required to accelerate from a standing start to liftoff ...

Terminal Aerodrome Forecast, a weather forecast specific to an airport covering ...

Irregular atmospheric motion causing an aircraft to experience bumps, altitude c...

A convective weather phenomenon producing lightning, heavy rain, turbulence, hai...

The boundary between the troposphere (where weather occurs) and the stratosphere...

The rate at which air temperature decreases with altitude. The standard lapse ra...

A layer of atmosphere where temperature increases with altitude instead of decre...

The direction the aircraft nose points relative to true north. True heading is d...

The actual speed of the aircraft through the air mass, corrected for altitude an...

The altitude at which pilots change from QNH altimeter setting to standard press...

The actual path of the aircraft over the ground. Track differs from heading when...

A regulatory notice filed with the FAA temporarily restricting certain aircraft ...

An authorization on a pilot certificate to fly a specific type of aircraft requi...

An aircraft electronic device that responds to ATC radar interrogation by transm...

An instrument showing the rate and direction of turn and coordination quality vi...

An airborne system that monitors transponder signals from nearby aircraft and pr...

A standard rectangular flight path around an airport runway consisting of upwind...

Ground movement of an aircraft under its own power on airport surfaces. Taxi ope...

A gas turbine engine where a large fan driven by the turbine section produces mo...

A gas turbine engine that drives a propeller through a reduction gearbox. Turbop...

The simplest form of gas turbine jet engine where all thrust comes from the exha...

The forward force produced by an engine to propel the aircraft. In jet engines, ...

A mechanism that redirects engine exhaust forward to provide braking force durin...

The time from loss of oxygen supply until a person can no longer take corrective...

A vestibular illusion where a pilot perceives straight-and-level flight as a ban...

A safety framework that identifies threats (environmental events beyond pilot co...

The fundamental navigation relationship where Distance equals Speed multiplied b...

The first 3000 feet of the runway or the first third of the runway, whichever is...

The generic term for systems including EGPWS that provide terrain awareness. TAW...

ATC information about other aircraft in the vicinity using clock position, dista...

The actual height above mean sea level. True altitude is what the altimeter shou...

A condition where the pilot has more tasks to perform than can be effectively ma...

A narrowing of attention focus that causes a pilot to fixate on one task or inst...

The speed regime between Mach 0.8 and 1.2 where both subsonic and supersonic air...

A small adjustable surface on a primary control surface that provides aerodynami...

Painted markings on airport surfaces including yellow taxiway centerlines, runwa...

The tendency of a helicopter fuselage to rotate in the direction opposite to mai...

The additional lift gained by a helicopter when transitioning from hover to forw...

An exhaust-driven compressor that increases air density entering the engine, mai...

The volume of aircraft operating in a given area of airspace. High traffic densi...

A non-government air-ground radio communication station providing airport adviso...

A metropolitan area that is warmer than surrounding rural areas due to human act...

Small fin-like devices on the wing upper surface that energize the boundary laye...

Designated airspeeds important to the operation of an aircraft, typically shown ...

The stall speed or minimum steady flight speed in landing configuration with ful...

The stall speed or minimum steady flight speed in a clean configuration with fla...

The never-exceed speed, indicated by a red line on the airspeed indicator. Excee...

Maximum structural cruising speed, the upper limit of the green arc on the airsp...

Rotation speed during takeoff at which the pilot applies back pressure to raise ...

Takeoff decision speed. Below V1, the takeoff can be safely rejected. At or abov...

Takeoff safety speed that must be attained by 35 feet above the runway. The mini...

Reference landing speed, typically 1.3 times VS0 for the landing weight and conf...

Minimum control speed with the critical engine inoperative. Below VMC, direction...

The greatest distance at which objects can be seen and identified. Reported in s...

Fine particles of pulverized rock from volcanic eruptions that are extremely haz...

A ground-based radio navigation aid transmitting radials in all directions. Pilo...

Flight rules allowing pilots to navigate by visual reference to the ground and o...

An instrument showing rate of climb or descent in feet per minute by measuring t...

An IFR approach where the pilot proceeds visually to the runway with ATC authori...

False sensations of motion or attitude caused by fluid dynamics in the inner ear...

Optical illusions affecting approach judgment including narrow runways appearing...

Low-altitude federal airways below 18000 feet MSL defined by VOR radials. Design...

Automated vertical flight path management by the FMS or GPS. VNAV can provide ve...

A defined point on a non-precision approach from which normal descent from MDA t...

Precipitation that evaporates before reaching the ground. Virga can produce wind...

A systematic method of looking outside the aircraft for traffic and terrain by f...

A graph showing the relationship between airspeed and load factor limits. The V-...

A system of lights beside the runway indicating approach angle. Two-bar VASI sho...

Mandatory procedures to avoid volcanic ash clouds that can cause total engine fa...

An IFR clearance allowing a pilot to fly in VFR conditions above clouds while ma...

A circular airflow pattern created at the wingtips where high-pressure air below...

A vertical or angled extension at the wingtip that reduces induced drag by weake...

A design feature where the wing is twisted so the angle of incidence decreases f...

Turbulent air generated by wingtip vortices behind an aircraft, particularly dan...

The process of calculating aircraft total weight and center of gravity position ...

A sudden change in wind speed or direction over a short distance. Low-level wind...

The leading edge of an advancing warm air mass riding over retreating cold air. ...

The direction from which the wind is blowing, expressed in degrees magnetic for ...

A GPS augmentation system providing improved accuracy, integrity, and availabili...

A predetermined geographical position defined by coordinates used for RNAV route...

An airborne radar system that detects precipitation and turbulence ahead of the ...

The ability to prioritize tasks and manage time effectively during various phase...

The angle between the desired course and the heading necessary to track that cou...

Changes in center of gravity during flight due to fuel burn, passenger movement,...

The continued rotation of a failed engine propeller or fan driven by airflow. Wi...

The exterior portion of the preflight inspection where the pilot physically walk...

Reduced aircraft performance on a runway with visible moisture. Landing distance...

A lateral or vertical deviation from the assigned route or altitude to avoid haz...

A preflight consultation of current and forecast weather conditions obtained fro...

Rotation of the aircraft about its vertical axis, controlled by the rudder. Yaw ...

Coordinated Universal Time (UTC) used as the standard time reference in aviation...