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Aviation Dictionary

Reference:

1 Airplane Flying Handbook
2 Pilot's Handbook of Aeronautical Knowledge
3 Instrument Procedures Handbook
4 Risk Management Handbook
5 Aviation Instructor Handbook
6 Seaplane Handbook
7 Balloon Handbook
8 Aeronautical Information Manual
9 Airplane Flying Handbook
10 Pilot Controller Glossary
11 Glider Handbook

C

Cabin altitude

2 Cabin pressure in terms of equivalent altitude above sea level.

Cabin pressurization

1 A condition where pressurized air is forced into the cabin simulating pressure conditions at a much lower altitude and increasing the aircraft occupants comfort.

Cage

2 The black markings on the ball instrument indicating its neutral position.

5 The black markings on the ball instrument indicating its neutral position.

Calibrated

2 The instrument indication compared with a standard value to determine the accuracy of the instrument.

5 The instrument indication compared with a standard value to determine the accuracy of the instrument.

Calibrated airspeed (CAS)

1 Indicated airspeed corrected for installation error and instrument error. Although manufacturers attempt to keep airspeed errors to a minimum, it is not possible to eliminate all errors throughout the airspeed operating range. At certain airspeeds an

2 The speed at which the aircraft is moving through the air, found by correcting IAS for instrument and position errors.

5 The speed at which the aircraft is moving through the air, found by correcting IAS for instrument and position errors.

Calibrated orifice

2 A hole of specific diameter used to delay the pressure change in the case of a vertical speed indicator.

5 A hole of specific diameter used to delay the pressure change in the case of a vertical speed indicator.

Camber

2 The camber of an airfoil is the characteristic curve of its upper and lower surfaces. The upper camber is more pronounced, while the lower camber is comparatively flat. This causes the velocity of the airflow immediately above the wing to be much hig

12 The curvature of a wing when looking at a cross section. A wing has upper camber on its top surface and lower camber on its bottom surface.

Cambered

1 The camber of an airfoil is the characteristic curve of its upper and lower surfaces. The upper camber is more pronounced, while the lower camber is comparatively flat. This causes the velocity of the airflow immediately above the wing to be much hig

Canard

2 A horizontal surface mounted ahead of the main wing to provide longitudinal stability and control. It may be a fixed, movable, or variable geometry surface, with or without control surfaces.

Canard configuration

2 A configuration in which the span of the forward wings is substantially less than that of the main wing.

Cantilever

2 A wing designed to carry loads without external struts.

Cap cloud

12 Also called a foehn cloud. These are clouds forming on mountain or ridge tops by cooling of moist air rising on the upwind side followed by warming and drying by downdrafts on the lee side.

Carburetor ice

1 Ice that forms inside the carburetor due to the temperature drop caused by the vaporization of the fuel. Induction system icing is an operational hazard because it can cut off the flow of the fuel/air charge or vary the fuel/air ratio.

Carburetor

1 1. Pressure: A hydromechanical device employing a closed feed system from the fuel pump to the discharge nozzle. It meters fuel through fixed jets according to the mass airflow through the throttle body and discharges it under a positive pressure. Pr

CAS

2 Calibrated airspeed.

5 Calibrated airspeed.

Cascade reverser

1 A thrust reverser normally found on turbofan engines in which a blocker door and a series of cascade vanes are used to redirect exhaust gases in a forward direction.

CBI

7 See computer-based instruction.

CBT

7 See computer-based training.

CDI

2 Course deviation indicator.

5 Course deviation indicator.

Ceiling

2 The height above the earth’s surface of the lowest layer of clouds, which is reported as broken or overcast, or the vertical visibility into an obscuration.

Center of gravity (CG)

1 The point at which an airplane would balance if it were possible to suspend it at that point. It is the mass center of the airplane, or the theoretical point at which the entire weight of the airplane is assumed to be concentrated. It may be expresse

2 The point at which an airplane would balance if it were possible to suspend it at that point. It is the mass center of the airplane, or the theoretical point at which the entire weight of the airplane is assumed to be concentrated. It may be expresse

Center-of-gravity limits

1 The specified forward and aft points within which the CG must be located during flight. These limits are indicated on pertinent airplane specifications.

2 The specified forward and aft points within which the CG must be located during flight. These limits are indicated on pertinent airplane specifications.

Center-of-gravity range

1 The distance between the forward and aft CG limits indicated on pertinent airplane specifications.

2 The distance between the forward and aft CG limits indicated on pertinent airplane specifications.

Center of pressure

2 A point along the wing chord line where lift is considered to be concentrated. For this reason, the center of pressure is commonly referred to as the center of lift.

12 The point along the wing chord line where lift is considered to be concentrated.

Centering

12 Adjusting circles while thermalling to provide the greatest average climb.

Center Radar ARTS Presentation/Processing (CENRAP)

4 CENRAP was developed to provide an alternative to a non-radar environment at terminal facilities should an ASR fail or malfunction. CENRAP sends aircraft radar beacon target information to the ASR terminal facility equipped with ARTS.

Centrifugal flow compressor

1 An impeller-shaped device that receives air at its center and slings air outward at high velocity into a diffuser for increased pressure. Also referred to as a radial outflow compressor

2 An impeller-shaped device that receives air at its center and slings the air outward at high velocity into a diffuser for increased pressure. Also referred to as a radial outflow compressor.

Centrifugal force

2 An outward force that opposes centripetal force, resulting from the effect of inertia during a turn.

12 The apparent force occurring in curvilinear motion acting to deflect objects outward from the axis of rotation. For instance, when pulling out of a dive, it is the force pushing you down in your seat.

Centripetal force

2 A center-seeking force directed inward toward the center of rotation created by the horizontal component of lift in turning flight.

12 The force in curvilinear motion acting toward the axis of rotation. For instance, when pulling out of a dive, it is the force that the seat exerts on the pilot to offset the centrifugal force.

CG

2 See center of gravity.

Changeover point (COP)

2 A point along the route or airway segment between two adjacent navigation facilities or waypoints where changeover in navigation guidance should occur.

4 A COP indicates the point where a frequency change is necessary between navigation aids, when other than the midpoint on an airway, to receive course guidance from the facility ahead of the aircraft instead of the one behind. These COPs divide an airway or route segment and ensure continuous reception of navigational signals at the prescribed minimum en route IFR altitude.

5 A point along the route or airway segment between two adjacent navigation facilities or waypoints where changeover in navigation guidance should occur.

Chart Supplements

1 A listing of data on record with the FAA on all open-to-the-public airports, seaplane bases, heliports, military facilities and selected private use airports specifically requested by the Department of Defense (DOD) for which a DOD instrument approac

4 Regional booklets published by Aeronautical Information Services that provides general information (graphic and textual) about all airports, both VFR and IFR (in the A/FD section), Notices, Associated Data and Airport Diagrams. The A/FD section includes runway length and width, runway surface, load bearing capacity, runway slope, airport services, and hazards such as birds and reduced visibility.

Chart Supplement U.S. (formerly Airport/Facility Directory)

2 An FAA publication containing information on all airports, communications, and NAVAIDs.

Checklist

2 A tool that is used as a human factors aid in aviation safety. It is a systematic and sequential list of all operations that must be performed to properly accomplish a task.

Chord line

1 An imaginary straight line drawn through an airfoil from the leading edge to the trailing edge.

2 An imaginary straight line drawn through an airfoil from the leading edge to the trailing edge.

12 An imaginary straight line drawn from the leading edge of an airfoil to the trailing edge.

Circling approach

2 A maneuver initiated by the pilot to align the aircraft with a runway for landing when a straight- in landing from an instrument approach is not possible or is not desirable.

5 A maneuver initiated by the pilot to align the aircraft with a runway for landing when a straight- in landing from an instrument approach is not possible or is not desirable.

Circuit breaker

1 A circuit-protecting device that opens the circuit in case of excess current flow. A circuit breaker differs from a fuse in that it can be reset without having to be replaced.

Class A airspace

2 Airspace from 18,000 feet MSL up to and including FL 600, including the airspace overlying the waters within 12 NM of the coast of the 48 contiguous states and Alaska; and designated international airspace beyond 12 NM of the coast of the 48 contiguo

5 Airspace from 18,000 feet MSL up to and including FL 600, including the airspace overlying the waters within 12 NM of the coast of the 48 contiguous states and Alaska; and designated international airspace beyond 12 NM of the coast of the 48 contiguous states and Alaska within areas of domestic radio navigational signal or A TC radar coverage, and within which domestic procedures are applied.

Class B airspace

2 Airspace from the surface to 10,000 feet MSL surrounding the nation’s busiest airports in terms of IFR operations or passenger numbers. The configuration of each Class B airspace is individually tailored and consists of a surface area and two or more

5 Airspace from the surface to 10,000 feet MSL surrounding the nation’s busiest airports in terms of IFR operations or passenger numbers. The configuration of each Class B airspace is individually tailored and consists of a surface area and two or more layers, and is designed to contain all published instrument procedures once an aircraft enters the airspace. For all aircraft, an ATC clearance is required to operate in the area, and aircraft so cleared receive separation services within the airspa

Class C airspace

2 Airspace from the surface to 4,000 feet above the airport elevation (charted in MSL) surrounding those airports having an operational control tower, serviced by radar approach control, and having a certain number of IFR operations or passenger number

5 Airspace from the surface to 4,000 feet above the airport elevation (charted in MSL) surrounding those airports having an operational control tower, serviced by radar approach control, and having a certain number of IFR operations or passenger numbers. Although the configuration of each Class C airspace area is individually tailored, the airspace usually consists of a 5 NM radius core surface area that extends from the surface up to 4,000 feet above the airport elevation, and a 10 NM radius shel

Class D airspace

2 Airspace from the surface to 2,500 feet above the airport elevation (charted in MSL) surrounding those airports that have an operational control tower. The configuration of each Class D airspace area is individually tailored, and when instrument proc

5 Airspace from the surface to 2,500 feet above the airport elevation (charted in MSL) surrounding those airports that have an operational control tower. The configuration of each Class D airspace area is individually tailored, and when instrument procedures are published, the airspace is normally designed to contain the procedures.

Class E airspace

2 Airspace that is not Class A, Class B, Class C, or Class D, and is controlled airspace.

5 Airspace that is not Class A, Class B, Class C, or Class D, and is controlled airspace.

Class G airspace

2 Airspace that is uncontrolled, except when associated with a temporary control tower, and has not been designated as Class A, Class B, Class C, Class D, or Class E airspace.

5 Airspace that is uncontrolled, except when associated with a temporary control tower, and has not been designated as Class A, Class B, Class C, Class D, or Class E airspace.

Clean configuration

2 A configuration in which all flight control surfaces have been placed to create minimum drag. In most aircraft this means flaps and gear retracted.

5 A configuration in which all flight control surfaces have been placed to create minimum drag. In most aircraft this means flaps and gear retracted.

Clear air turbulence

1 Turbulence not associated with any visible moisture.

Clearance

2 ATC permission for an aircraft to proceed under specified traffic conditions within controlled airspace, for the purpose of providing separation between known aircraft.

5 ATC permission for an aircraft to proceed under specified traffic conditions within controlled airspace, for the purpose of providing separation between known aircraft.

Clearance delivery

2 Control tower position responsible for transmitting departure clearances to IFR flights.

5 Control tower position responsible for transmitting departure clearances to IFR flights.

Clearance limit

2 The fix, point, or location to which an aircraft is cleared when issued an air traffic clearance.

5 The fix, point, or location to which an aircraft is cleared when issued an air traffic clearance.

Clearance on request

2 An IFR clearance not yet received after filing a flight plan.

5 An IFR clearance not yet received after filing a flight plan.

Clearance void time

2 Used by ATC, the time at which the departure clearance is automatically canceled if takeoff has not been made. The pilot must obtain a new clearance or cancel the IFR flight plan if not off by the specified time.

5 Used by ATC, the time at which the departure clearance is automatically canceled if takeoff has not been made. The pilot must obtain a new clearance or cancel the IFR flight plan if not off by the specified time.

Clear ice

2 Glossy, clear, or translucent ice formed by the relatively slow freezing of large, supercooled water droplets.

5 Glossy, clear, or translucent ice formed by the relatively slow freezing of large, supercooled water droplets.

Climb gradient

1 The ratio between distance traveled and altitude gained

Closely Spaced Dependent Approaches

4 Identifies dependent approaches to parallel runways spaced less than 2,500 feet apart where ATC is permitted to apply reduced diagonal separation and special wake turbulence procedures. turbulence procedures.

Cloud streets

12 Parallel rows of cumulus clouds. Each row can be as short as 10 miles or as long as a 100 miles or more.

Cockpit Display of Traffic Information (CDTI)

4 The display and user interface for information about air traffic within approximately 80 miles. It typically combines and shows traffic data from TCAS, TIS-B, and ADS-B. Depending on features, the display may also show terrain, weather, and navigation information.

Cockpit resource management

1 Techniques designed to reduce pilot errors and manage errors that do occur utilizing cockpit human resources. The assumption is that errors are going to happen in a complex system with error-prone humans.

Coefficient of lift (CL)

1 See lift coefficient.

2 The ratio between lift pressure and dynamic pressure.

Coffin corner

1 The flight regime where any increase in airspeed will induce high speed Mach buffet and any decrease in airspeed will induce low speed Mach buffet.

Cognitive domain

7 A grouping of levels of learning associated with mental activity. In order of increasing complexity, the domains are knowledge, comprehension, application, analysis, synthesis, and evaluation.

Cold front

2 The boundary between two air masses where cold air is replacing warm air.

Cold soaked

12 Condition of a self-launch or sustainer engine making it difficult or impossible to start in flight due to long- time exposure to cold temperatures. Usually occurs after a long soaring flight at altitudes with cold temperatures (e.g., a wave flight).

Collision Hazard

4 A condition, event, or circumstance that could induce an occurrence of a collision or surface accident or incident.

Columns

4 See database columns.

Combustion chamber

1 The section of the engine into which fuel is injected and burned.

Common traffic advisory frequency (CTAF)

1 The common frequency used by airport traffic to announce position reports in the vicinity of the airport.

Compact disk (CD)

7 A small plastic optical disk which contains recorded music or computer data. Also, a popular format for storing information digitally. The major advantage of a CD is its capability to store enormous amounts of information.

Compass course

2 A true course corrected for variation and deviation errors.

5 A true course corrected for variation and deviation errors.

Compass locator

2 A low-power, low- or medium-frequency (L/MF) radio beacon installed at the site of the outer or middle marker of an ILS.

5 A low-power, low- or medium-frequency (L/MF) radio beacon installed at the site of the outer or middle marker of an ILS.

Compass rose

2 A small circle graduated in 360° increments, to show direction expressed in degrees.

5 A small circle graduated in 360° increments, printed on navigational charts to show the amount of compass variation at different locations, or on instruments to indicate direction.

Complex aircraft

1 An aircraft with retractable landing gear, flaps, and a controllable-pitch propeller, or one that is turbine-powered.

2 An aircraft with retractable landing gear, flaps, and a controllable-pitch propeller.

Comprehensiveness

7 The degree to which a test measures the overall objective.

Compressor pressure ratio

2 The ratio of compressor discharge pressure to compressor inlet pressure.

Compression ratio

1 1. In a reciprocating engine, the ratio of the volume of an engine cylinder with the piston at the bottom center to the volume with the piston at top center. 2. In a turbine engine, the ratio of the pressure of the air at the discharge to the pressur

Compressor stall

2 In gas turbine engines, a condition in an axial-flow compressor in which one or more stages of rotor blades fail to pass air smoothly to the succeeding stages. A stall condition is caused by a pressure ratio that is incompatible with the engine rpm.

Compressor bleed air

1 See bleed air.

Compressor bleed valves

1 See bleed valve.

Compressor section

1 The section of a turbine engine that increases the pressure and density of the air flowing through the engine.

Compressor stall

1 In gas turbine engines, a condition in an axial-flow compressor in which one or more stages of rotor blades fail to pass air smoothly to the succeeding stages. A stall condition is caused by a pressure ratio that is incompatible with the engine rpm C

Compressor surge

1 A severe compressor stall across the entire compressor that can result in severe damage if not quickly corrected. This condition occurs with a complete stoppage of airflow or a reversal of airflow.

Computer-assisted instruction

7 Instruction in which the instructor is responsible for the class and uses the computer to assist in the instruction.

Computer-based training (CBT)

7 The use of the computer as a training device. CBT is sometimes called computer-based instruction (CBI); the terms and acronyms are synonymous and may be used interchangeably.

Computer navigation fix

2 A point used to define a navigation track for an airborne computer system such as GPS or FMS.

5 A point used to define a navigation track for an airborne computer system such as GPS or FMS.

Concentric rings

2 Dashed-line circles depicted in the plan view of IAP charts, outside of the reference circle, that show en route and feeder facilities.

5 Dashed-line circles depicted in the plan view of IAP charts, outside of the reference circle, that show en route and feeder facilities.

Condensation

2 A change of state of water from a gas (water vapor) to a liquid.

Condensation nuclei

2 Small particles of solid matter in the air on which water vapor condenses.

Condition

7 The second part of a performance-based objective which describes the framework under which the skill or behavior will be demonstrated.

Condition lever

1 In a turbine engine, a powerplant control that controls the flow of fuel to the engine. The condition lever sets the desired engine rpm within a narrow range between that appropriate for ground and flight operations.

Cone of confusion

2 A cone-shaped volume of airspace directly above a VOR station where no signal is received, causing the CDI to fluctuate.

5 A cone-shaped volume of airspace directly above a VOR station where no signal is received, causing the CDI to fluctuate.

Configuration

1 This is a general term, which normally refers to the position of the landing gear and flaps.

2 This is a general term, which normally refers to the position of the landing gear and flaps.

Confusion between the symbol and the symbolized object

7 Results when a word is confused with what it is meant to represent. Words and symbols create confusion when they mean different things to different people.

Constant speed propeller

1 A controllable-pitch propeller whose pitch is automatically varied in flight by a governor to maintain a constant rpm in spite of varying air loads.

2 A controllable-pitch propeller whose pitch is automatically varied in flight by a governor to maintain a constant rpm in spite of varying air loads.

Control touch

1 The ability to sense the action of the airplane and its probable actions in the immediate future, with regard to attitude and speed variations, by sensing and evaluation of varying pressures and resistance of the control surfaces transmitted through

Continuous flow oxygen system

2 System that supplies a constant supply of pure oxygen to a rebreather bag that dilutes the pure oxygen with exhaled gases and thus supplies a healthy mix of oxygen and ambient air to the mask. Primarily used in passenger cabins of commercial airliner

Control and performance

2 A method of attitude instrument flying in which one instrument is used for making attitude changes, and the other instruments are used to monitor the progress of the change.

5 A method of attitude instrument flying in which one instrument is used for making attitude changes, and the other instruments are used to monitor the progress of the change.

Control display unit

2 A display interfaced with the master computer, providing the pilot with a single control point for all navigations systems, thereby reducing the number of required flight deck panels.

5 A display interfaced with the master computer, providing the pilot with a single control point for all navigations systems, thereby reducing the number of required flight deck panels.

Controllability

1 A measure of the response of an aircraft relative to the pilot’s flight control inputs.

2 A measure of the response of an aircraft relative to the pilot’s flight control inputs.

Controllable-pitch propeller (CPP)

1 A propeller in which the blade angle can be changed during flight by a control in the cockpit.

2 A type of propeller with blades that can be rotated around their long axis to change their pitch. If the pitch can be set to negative values, the reversible propeller can also create reverse thrust for braking or reversing without the need of changin

Controlled airspace

2 An airspace of defined dimensions within which A TC service is provided to IFR and VFR flights in accordance with the airspace classification. It includes Class A, Class B, Class C, Class D, and Class E airspace.

5 An airspace of defined dimensions within which A TC service is provided to IFR and VFR flights in accordance with the airspace classification. It includes Class A, Class B, Class C, Class D, and Class E airspace.

Control pressures

2 The amount of physical exertion on the control column necessary to achieve the desired attitude.

5 The amount of physical exertion on the control column necessary to achieve the desired attitude.

Convection

12 Transport and mixing of an atmospheric variable due to vertical mass motions (e.g., updrafts).

Convective condensation level (CCL)

12 The level at which cumulus forms from surface-based convection. Under this level, the air is dry adiabatic and the mixing ratio is constant.

Convective weather.

2 Unstable, rising air found in cumiliform clouds.

5 Unstable, rising air found in cumiliform clouds.

Convective SIGMET

2 Weather advisory concerning convective weather significant to the safety of all aircraft, including thunderstorms, hail, and tornadoes.

5 Weather advisory concerning convective weather significant to the safety of all aircraft, including thunderstorms, hail, and tornadoes.

Conventional landing gear

1 Landing gear employing a third rear-mounted wheel. These airplanes are also sometimes referred to as tailwheel airplanes.

2 Landing gear employing a third rear-mounted wheel. These airplanes are also sometimes referred to as tailwheel airplanes.

Conventional tail

12 A glider design with the horizontal stabilizer mounted at the bottom of the vertical stabilizer.

Convergence

12 A net increase in the mass of air over a specified area due to horizontal wind speed and/or direction changes. When convergence occurs in lower levels, it is usually associated with upward air motions.

Convergence zone

12 An area of convergence, sometimes several miles wide, at other times very narrow. These zones often provide organized lift for many miles (e.g., a sea-breeze front).

Cooperative or group learning.

7 An instructional strategy which organizes learners into small groups so that they can work together to maximize their own and each other’s learning.

Coordinated flight

1 Application of all appropriate flight and power controls to prevent slipping or skidding in any flight condition.

2 Flight with a minimum disturbance of the forces maintaining equilibrium, established via effective control use.

5 Flight with a minimum disturbance of the forces maintaining equilibrium, established via effective control use.

Coordination

1 The ability to use the hands and feet together subconsciously and in the proper relationship to produce desired results in the airplane.

COP

2 See changeover point.

5 See changeover point.

Core airflow

1 Air drawn into the engine for the gas generator.

Correlation

7 A basic level of learning where the learner can associate what has been learned, understood, and applied with previous or subsequent learning.

Coriolis illusion

2 The illusion of rotation or movement in an entirely different axis, caused by an abrupt head movement, while in a prolonged constant-rate turn that has ceased to stimulate the brain’s motion sensing system.

5 The illusion of rotation or movement in an entirely different axis, caused by an abrupt head movement, while in a prolonged constant rate turn that has ceased stimulating the brain’s motion sensing system.

Coupled ailerons and rudder

2 Rudder and ailerons are connected with interconnected springs in order to counteract adverse yaw. Can be overridden if it becomes necessary to slip the aircraft.

Course

2 The intended direction of flight in the horizontal plane measured in degrees from north.

Course of training

7 A complete series of studies leading to attainment of a specific goal, such as a certificate of completion, graduation, or an academic degree.

Cowl flaps

1 Devices arranged around certain air-cooled engine cowlings which may be opened or closed to regulate the flow of air around the engine.

2 Shutter-like devices arranged around certain air-cooled engine cowlings, which may be opened or closed to regulate the flow of air around the engine.

Crab

1 A flight condition in which the nose of the airplane is pointed into the wind a sufficient amount to counteract a crosswind and maintain a desired track over the ground.

Crazing

1 Small fractures in aircraft windshields and windows caused from being exposed to the ultraviolet rays of the sun and temperature extremes.

Crew resource management (CRM)

2 The application of team management concepts in the flight deck environment. It was initially known as cockpit resource management, but as CRM programs evolved to include cabin crews, maintenance personnel, and others, the phrase “crew resource manage

5 The effective use of all available resources—human, hardware, and information.

7 The application of team management concepts in the flight deck environment. It was initially known as cockpit resource management, but as CRM programs evolved to include cabin crews, maintenance personnel and others, the phrase “crew resource management” has been adopted. This includes single pilots, as in most general aviation aircraft. Pilots of small aircraft, as well as crews of larger aircraft, must make effective use of all available resources; human resources, hardware, and information. A

Criteria

7 The third part of a performance-based objective, descriptions of standards that will be used to measure the accomplishment of the objective.

Criterion-referenced testing

7 System of testing where learners are graded against a carefully written, measurable standard or criterion rather than against each other.

Critical angle of attack

2 The angle of attack at which a wing stalls regardless of airspeed, flight attitude, or weight.

12 Angle of attack, typically around 18°, beyond which a stall occurs. The critical angle of attack can be exceeded at any airspeed and at any nose attitude.

Critical altitude

1 The maximum altitude under standard atmospheric conditions at which a turbocharged engine can produce its rated horsepower.

Critical angle of attack

1 The angle of attack at which a wing stalls regardless of airspeed, flight attitude, or weight.

Critical areas

2 Areas where disturbances to the ILS localizer and glideslope courses may occur when surface vehicles or aircraft operate near the localizer or glideslope antennas.

5 Areas where disturbances to the ILS localizer and glide slope courses may occur when surface vehicles or aircraft operate near the localizer or glide slope antennas.

Critical engine

1 The engine whose failure has the most adverse effect on directional control.

CRM

2 See crew resource management.

5 See crew resource management.

7 See crew resource management.

Cross-check

2 The first fundamental skill of instrument flight, also known as “scan,” the continuous and logical observation of instruments for attitude and performance information.

5 The first fundamental skill of instrument flight, also known as “scan,” the continuous and logical observation of instruments for attitude and performance information.

Cross controlled

1 A condition where aileron deflection is in the opposite direction of rudder deflection.

Cross-country

12 In soaring, any flight out of gliding range of the takeoff airfield. Note that this is different from the definitions in the 14 CFR for meeting the experience requirements for various pilot certificates and/or ratings.

Crossfeed

1 A system that allows either engine on a twin- engine airplane to draw fuel from any fuel tank.

Crosswind component

1 The wind component, measured in knots, at 90 degrees to the longitudinal axis of the runway.

Cruise clearance

2 An ATC clearance issued to allow a pilot to conduct flight at any altitude from the minimum IFR altitude up to and including the altitude specified in the clearance. Also authorizes a pilot to proceed to and make an approach at the destination airpor

5 An ATC clearance issued to allow a pilot to conduct flight at any altitude from the minimum IFR altitude up to and including the altitude specified in the clearance. Also authorizes a pilot to proceed to and make an approach at the destination airport.

Cumulus congestus

12 A cumulus cloud of significant vertical extent and usually displaying sharp edges. In warm climates, these sometimes produce precipitation. Also called towering cumulus, these clouds indicate that thunderstorm activity may soon occur.

Cumulonimbus (CB)

12 Also called thunderclouds, these are deep convective clouds with a cirrus anvil and may contain any of the characteristics of a thunderstorm: thunder, lightning, heavy rain, hail, strong winds, turbulence, and even tornadoes.

Current limiter

1 A device that limits the generator output to a level within that rated by the generator manufacturer.

Current induction

2 An electrical current being induced into, or generated in, any conductor that is crossed by lines of flux from any magnet.

5 An electrical current being induced into, or generated in, any conductor that is crossed by lines of flux from any magnet.

Curriculum

7 A set of courses in an area of specialization offered by an educational institution. A curriculum for a pilot school usually includes courses for the various pilot certificates and ratings.

Cut-away

7 Model of an object that is built in sections so it can be taken apart to reveal the inner structure.