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A
14 CFR. See Title 14 of the Code of Federal Regulations.
100-hour inspection. An inspection identical in scope to
an annual inspection. Conducted every 100 hours of flight
on aircraft of under 12,500 pounds that are used to carry
passengers for hire.
Absolute accuracy. The ability to determine present position
in space independently, and is most often used by pilots.
Absolute altitude. The actual distance between an aircraft
and the terrain over which it is flying.
Absolute pressure. Pressure measured from the reference
of zero pressure, or a vacuum.
A.C. Alternating current.
Acceleration. Force involved in overcoming inertia, and
which may be defined as a change in velocity per unit of time.
Acceleration error. A magnetic compass error apparent when
the aircraft accelerates while flying on an easterly or westerly
heading, causing the compass card to rotate toward North.
Accelerate-go distance. The distance required to accelerate
to V1 with all engines at takeoff power, experience an engine
failure at V 1, and continue the takeoff on the remaining
engine(s). The runway required includes the distance required
to climb to 35 feet by which time V2 speed must be attained.
Accelerate-stop distance. The distance required to accelerate
to V1 with all engines at takeoff power, experience an engine
failure at V1, and abort the takeoff and bring the airplane to
a stop using braking action only (use of thrust reversing is
not considered).
Accelerometer. A part of an inertial navigation system
(INS) that accurately measures the force of acceleration in
one direction.
Glossary
ADC. See air data computer.
ADF. See automatic direction finder.
ADI. See attitude director indicator.
Adiabatic cooling. A process of cooling the air through
expansion. For example, as air moves up slope it expands with
the reduction of atmospheric pressure and cools as it expands.
Adiabatic heating. A process of heating dry air through
compression. For example, as air moves down a slope it is
compressed, which results in an increase in temperature.
Adjustable-pitch propeller. A propeller with blades whose
pitch can be adjusted on the ground with the engine not
running, but which cannot be adjusted in flight. Also referred
to as a ground adjustable propeller. Sometimes also used to
refer to constant-speed propellers that are adjustable in flight.
Adjustable stabilizer. A stabilizer that can be adjusted in
flight to trim the airplane, thereby allowing the airplane to
fly hands-off at any given airspeed.
ADM. See aeronautical decision-making.
ADS-B. See automatic dependent surveillance-broadcast.
Advection fog. Fog resulting from the movement of warm,
humid air over a cold surface.
Adverse yaw. A condition of flight in which the nose of an
airplane tends to yaw toward the outside of the turn. This is
caused by the higher induced drag on the outside wing, which
is also producing more lift. Induced drag is a by-product of
the lift associated with the outside wing.
Aerodynamics. The science of the action of air on an object,
and with the motion of air on other gases. Aerodynamics
deals with the production of lift by the aircraft, the relative
wind, and the atmosphere.
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Aeronautical chart. A map used in air navigation containing
all or part of the following: topographic features, hazards and
obstructions, navigation aids, navigation routes, designated
airspace, and airports.
Aeronautical decision-making (ADM). A systematic
approach to the mental process used by pilots to consistently
determine the best course of action in response to a given
set of circumstances.
Agonic line. An irregular imaginary line across the surface of
the Earth along which the magnetic and geographic poles are
in alignment, and along which there is no magnetic variation.
Ailerons. Primary flight control surfaces mounted on the
trailing edge of an airplane wing, near the tip. Ailerons control
roll about the longitudinal axis.
Aircraft. A device that is used, or intended to be used, for
flight.
Aircraft altitude. The actual height above sea level at which
the aircraft is flying.
Aircraft approach category. A performance grouping of
aircraft based on a speed of 1.3 times the stall speed in the
landing configuration at maximum gross landing weight.
Air data computer (ADC). An aircraft computer that
receives and processes pitot pressure, static pressure, and
temperature to calculate very precise altitude, indicated
airspeed, true airspeed, and air temperature.
Airfoil. Any surface, such as a wing, propeller, rudder, or
even a trim tab, which provides aerodynamic force when it
interacts with a moving stream of air.
Air mass. An extensive body of air having fairly uniform
properties of temperature and moisture.
AIRMET. Inflight weather advisory issued as an amendment
to the area forecast, concerning weather phenomena of
operational interest to all aircraft and that is potentially
hazardous to aircraft with limited capability due to lack of
equipment, instrumentation, or pilot qualifications.
Airplane. An engine-driven, fixed-wing aircraft heavier than
air that is supported in flight by the dynamic reaction of air
against its wings.
Airplane Flight Manual (AFM). A document developed
by the airplane manufacturer and approved by the Federal
Aviation Administration (FAA). It is specific to a particular
make and model airplane by serial number and it contains
operating procedures and limitations.
Airplane Owner/Information Manual. A document
developed by the airplane manufacturer containing general
information about the make and model of an airplane. The
airplane owner’s manual is not FAA approved and is not
specific to a particular serial numbered airplane. This manual
is not kept current, and therefore cannot be substituted for
the AFM/POH.
Airport diagram. The section of an instrument approach
procedure chart that shows a detailed diagram of the
airport. This diagram includes surface features and airport
configuration information.
Airport/Facility Directory (A/FD). See Chart Supplement
U.S.
Airport surface detection equipment (ASDE). Radar
equipment specifically designed to detect all principal
features and traffic on the surface of an airport, presenting the
entire image on the control tower console; used to augment
visual observation by tower personnel of aircraft and/or
vehicular movements on runways and taxiways.
Airport surveillance radar (ASR). Approach control
radar used to detect and display an aircraft’s position in the
terminal area.
Airport surveillance radar approach. An instrument
approach in which ATC issues instructions for pilot
compliance based on aircraft position in relation to the final
approach course and the distance from the end of the runway
as displayed on the controller’s radar scope.
Air route surveillance radar (ARSR). Air route traffic
control center (ARTCC) radar used primarily to detect
and display an aircraft’s position while en route between
terminal areas.
Air route traffic control center (ARTCC). Provides ATC
service to aircraft operating on IFR flight plans within
controlled airspace and principally during the en route phase
of flight.
Airspeed. Rate of the aircraft’s progress through the air.
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Airspeed indicator. A differential pressure gauge that
measures the dynamic pressure of the air through which the
aircraft is flying. Displays the craft’s airspeed, typically in
knots, to the pilot.
Air traffic control radar beacon system (ATCRBS).
Sometimes called secondary surveillance radar (SSR), which
utilizes a transponder in the aircraft. The ground equipment is
an interrogating unit, in which the beacon antenna is mounted
so it rotates with the surveillance antenna. The interrogating
unit transmits a coded pulse sequence that actuates the aircraft
transponder. The transponder answers the coded sequence
by transmitting a preselected coded sequence back to the
ground equipment, providing a strong return signal and
positive aircraft identification, as well as other special data.
Airway. An airway is based on a centerline that extends from
one navigation aid or intersection to another navigation aid
(or through several navigation aids or intersections); used
to establish a known route for en route procedures between
terminal areas.
Airworthiness Certificate. A certificate issued by the FAA
to all aircraft that have been proven to meet the minimum
standards set down by the Code of Federal Regulations.
Airworthiness Directive. A regulatory notice sent out by
the FAA to the registered owner of an aircraft informing
the owner of a condition that prevents the aircraft from
continuing to meet its conditions for airworthiness.
Airworthiness Directives (AD notes) are to be complied with
within the required time limit, and the fact of compliance,
the date of compliance, and the method of compliance are
recorded in the aircraft’s maintenance records.
Alert area. An area in which there is a high volume of pilot
training or an unusual type of aeronautical activity.
Almanac data. Information the global positioning system
(GPS) receiver can obtain from one satellite which describes
the approximate orbital positioning of all satellites in the
constellation. This information is necessary for the GPS
receiver to know what satellites to look for in the sky at a
given time.
ALS. See approach lighting system.
Alternate airport. An airport designated in an IFR flight
plan, providing a suitable destination if a landing at the
intended airport becomes inadvisable.
Alternate static source valve. A valve in the instrument static
air system that supplies reference air pressure to the altimeter,
airspeed indicator, and vertical speed indicator if the normal
static pickup should become clogged or iced over.
Altimeter. A flight instrument that indicates altitude by
sensing pressure changes.
Altimeter setting. Station pressure (the barometric pressure
at the location the reading is taken) which has been corrected
for the height of the station above sea level.
Altitude engine. A reciprocating aircraft engine having a
rated takeoff power that is producible from sea level to an
established higher altitude.
Ambient pressure. The pressure in the area immediately
surrounding the aircraft.
Ambient temperature. The temperature in the area
immediately surrounding the aircraft.
AME. See aviation medical examiner.
Amendment status. The circulation date and revision
number of an instrument approach procedure, printed above
the procedure identification.
Ammeter. An instrument installed in series with an electrical
load used to measure the amount of current flowing through
the load.
Aneroid. The sensitive component in an altimeter or
barometer that measures the absolute pressure of the air.
It is a sealed, flat capsule made of thin disks of corrugated
metal soldered together and evacuated by pumping all of
the air out of it.
Aneroid barometer. An instrument that measures the
absolute pressure of the atmosphere by balancing the weight
of the air above it against the spring action of the aneroid.
Angle of attack. The angle of attack is the angle at which
relative wind meets an airfoil. It is the angle that is formed
by the chord of the airfoil and the direction of the relative
wind or between the chord line and the flight path. The
angle of attack changes during a flight as the pilot changes
the direction of the aircraft and is related to the amount of
lift being produced.
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Angle of incidence. The acute angle formed between the
chord line of an airfoil and the longitudinal axis of the aircraft
on which it is mounted.
Anhedral. A downward slant from root to tip of an aircraft’s
wing or horizontal tail surface.
Annual inspection. A complete inspection of an aircraft and
engine, required by the Code of Federal Regulations, to be
accomplished every 12 calendar months on all certificated
aircraft. Only an A&P technician holding an Inspection
Authorization can conduct an annual inspection.
Anti-ice. Preventing the accumulation of ice on an aircraft
structure via a system designed for that purpose.
Antiservo tab. An adjustable tab attached to the trailing edge
of a stabilator that moves in the same direction as the primary
control. It is used to make the stabilator less sensitive.
Approach lighting system (ALS). Provides lights that will
penetrate the atmosphere far enough from touchdown to
give directional, distance, and glidepath information for safe
transition from instrument to visual flight.
Area chart. Part of the low-altitude en route chart series,
this chart furnishes terminal data at a larger scale for
congested areas.
Area forecast (FA). A report that gives a picture of clouds,
general weather conditions, and visual meteorological
conditions (VMC) expected over a large area encompassing
several states.
Area navigation (RNAV). Allows a pilot to fly a selected
course to a predetermined point without the need to overfly
ground-based navigation facilities, by using waypoints.
Arm. See moment arm.
ARSR. See air route surveillance radar.
ARTCC. See air route traffic control center.
ASDE. See airport surface detection equipment.
ASOS. See Automated Surface Observing System.
Aspect ratio. Span of a wing divided by its average chord.
ASR. See airport surveillance radar.
Asymmetric thrust. Also known as P-factor. A tendency for
an aircraft to yaw to the left due to the descending propeller
blade on the right producing more thrust than the ascending
blade on the left. This occurs when the aircraft’s longitudinal
axis is in a climbing attitude in relation to the relative wind.
The P-factor would be to the right if the aircraft had a
counterclockwise rotating propeller.
ATC. Air Traffic Control.
ATCRBS. See air traffic control radar beacon system.
ATIS. See automatic terminal information service.
Atmospheric propagation delay. A bending of the
electromagnetic (EM) wave from the satellite that creates
an error in the GPS system.
Attitude. A personal motivational predisposition to respond
to persons, situations, or events in a given manner that can,
nevertheless, be changed or modified through training as sort
of a mental shortcut to decision-making.
Attitude and heading reference system (AHRS). A system
composed of three-axis sensors that provide heading, attitude,
and yaw information for aircraft. AHRS are designed to
replace traditional mechanical gyroscopic flight instruments
and provide superior reliability and accuracy.
Attitude director indicator (ADI). An aircraft attitude
indicator that incorporates flight command bars to provide
pitch and roll commands.
Attitude indicator. The foundation for all instrument flight,
this instrument reflects the airplane’s attitude in relation to
the horizon.
Attitude instrument flying. Controlling the aircraft by
reference to the instruments rather than by outside visual cues.
Attitude management. The ability to recognize hazardous
attitudes in oneself and the willingness to modify them as
necessary through the application of an appropriate antidote
thought.
Autokinesis. Nighttime visual illusion that a stationary light
is moving, which becomes apparent after several seconds of
staring at the light.
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Automated Surface Observing System (ASOS). Weather
reporting system which provides surface observations every
minute via digitized voice broadcasts and printed reports.
Automated Weather Observing System (AWOS).
Automated weather reporting system consisting of various
sensors, a processor, a computer-generated voice subsystem,
and a transmitter to broadcast weather data.
Automatic dependent surveillance—broadcast (ADS–B).
A function on an aircraft or vehicle that periodically
broadcasts its state vector (i.e., horizontal and vertical
position, horizontal and vertical velocity) and other
information.
Automatic direction finder (ADF). Electronic navigation
equipment that operates in the low- and medium-frequency
bands. Used in conjunction with the ground-based
nondirectional beacon (NDB), the instrument displays the
number of degrees clockwise from the nose of the aircraft
to the station being received.
Automatic terminal information service (ATIS). The
continuous broadcast of recorded non-control information in
selected terminal areas. Its purpose is to improve controller
effectiveness and relieve frequency congestion by automating
repetitive transmission of essential but routine information.
Autopilot. An automatic flight control system which keeps
an aircraft in level flight or on a set course. Automatic pilots
can be directed by the pilot, or they may be coupled to a radio
navigation signal.
Aviation medical examiner (AME). A physician with
training in aviation medicine designated by the Civil
Aerospace Medical Institute (CAMI).
Aviation Routine Weather Report (METAR). Observation
of current surface weather reported in a standard international
format.
AWOS. See Automated Weather Observing System.
Axes of an aircraft. Three imaginary lines that pass through
an aircraft’s center of gravity. The axes can be considered
as imaginary axles around which the aircraft rotates. The
three axes pass through the center of gravity at 90° angles to
each other. The axis from nose to tail is the longitudinal axis
(pitch), the axis that passes from wingtip to wingtip is the
lateral axis (roll), and the axis that passes vertically through
the center of gravity is the vertical axis (yaw).
Axial flow compressor. A type of compressor used in a
turbine engine in which the airflow through the compressor
is essentially linear. An axial-flow compressor is made up of
several stages of alternate rotors and stators. The compressor
ratio is determined by the decrease in area of the succeeding
stages.
Azimuth card. A card that may be set, gyroscopically
controlled, or driven by a remote compass.
B
Back course (BC). The reciprocal of the localizer course
for an ILS. When flying a back-course approach, an aircraft
approaches the instrument runway from the end at which the
localizer antennas are installed.
Balance tab. An auxiliary control mounted on a primary
control surface, which automatically moves in the direction
opposite the primary control to provide an aerodynamic
assist in the movement of the control.
Baro-aiding. A method of augmenting the GPS integrity
solution by using a nonsatellite input source. To ensure that
baro-aiding is available, the current altimeter setting must
be entered as described in the operating manual.
Barometric scale. A scale on the dial of an altimeter to which
the pilot sets the barometric pressure level from which the
altitude shown by the pointers is measured.
Basic empty weight (GAMA). Basic empty weight
includes the standard empty weight plus optional and special
equipment that has been installed.
BC. See back course.
Bernoulli’s Principle. A principle that explains how the
pressure of a moving fluid varies with its speed of motion.
An increase in the speed of movement causes a decrease in
the fluid’s pressure.
Biplanes. Airplanes with two sets of wings.
Block altitude. A block of altitudes assigned by ATC to
allow altitude deviations; for example, “Maintain block
altitude 9 to 11 thousand.”
Bypass ratio. The ratio of the mass airflow in pounds per
second through the fan section of a turbofan engine to the
mass airflow that passes through the gas generator portion
of the engine.
G-6
C
Cabin altitude. Cabin pressure in terms of equivalent altitude
above sea level.
Cage. The black markings on the ball instrument indicating
its neutral position.
Calibrated. The instrument indication compared with a
standard value to determine the accuracy of the instrument.
Calibrated orifice. A hole of specific diameter used to delay
the pressure change in the case of a vertical speed indicator.
Calibrated airspeed. The speed at which the aircraft
is moving through the air, found by correcting IAS for
instrument and position errors.
Camber. 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 higher than that below the wing.
Canard. 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. A configuration in which the span
of the forward wings is substantially less than that of the
main wing.
Cantilever. A wing designed to carry loads without external
struts.
CAS. Calibrated airspeed.
CDI. Course deviation indicator.
Ceiling. 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). 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 expressed in inches from the
reference datum, or in percentage of mean aerodynamic
chord (MAC). The location depends on the distribution of
weight in the airplane.
Center of gravity limits. 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. The distance between the forward
and aft CG limits indicated on pertinent airplane specifications.
Center of pressure. 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.
Centrifugal flow compressor. 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. An outward force that opposes centripetal
force, resulting from the effect of inertia during a turn.
Centripetal force. A center-seeking force directed inward
toward the center of rotation created by the horizontal
component of lift in turning flight.
CG. See center of gravity.
Changeover point (COP). A point along the route or
airway segment between two adjacent navigation facilities
or waypoints where changeover in navigation guidance
should occur.
Chart Supplement U.S. (formerly Airport/Facility
Directory). An FAA publication containing information on
all airports, communications, and NAVAIDs.
Checklist. 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. An imaginary straight line drawn through an
airfoil from the leading edge to the trailing edge.
Circling approach. 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.
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Class A airspace. 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 ATC radar coverage,
and within which domestic procedures are applied.
Class B airspace. 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 airspace.
Class C airspace. 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 shelf area that extends from
1,200 feet to 4,000 feet above the airport elevation.
Class D airspace. 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. Airspace that is not Class A, Class B, Class
C, or Class D, and is controlled airspace.
Class G airspace. 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. A configuration in which all flight
control surfaces have been placed to create minimum drag.
In most aircraft this means flaps and gear retracted.
Clearance. 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. Control tower position responsible for
transmitting departure clearances to IFR flights.
Clearance limit. The fix, point, or location to which an
aircraft is cleared when issued an air traffic clearance.
Clearance on request. An IFR clearance not yet received
after filing a flight plan.
Clearance void time. 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. Glossy, clear, or translucent ice formed by the
relatively slow freezing of large, supercooled water droplets.
Coefficient of lift (CL). The ratio between lift pressure and
dynamic pressure.
Cold front. The boundary between two air masses where
cold air is replacing warm air.
Compass course. A true course corrected for variation and
deviation errors.
Compass locator. 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. A small circle graduated in 360° increments,
to show direction expressed in degrees.
Complex aircraft. An aircraft with retractable landing gear,
flaps, and a controllable-pitch propeller.
Compressor pressure ratio. The ratio of compressor
discharge pressure to compressor inlet pressure.
Compressor stall. 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 stall will be
indicated by a rise in exhaust temperature or rpm fluctuation,
and if allowed to continue, may result in flameout and
physical damage to the engine.
Computer navigation fix. A point used to define a
navigation track for an airborne computer system such as
GPS or FMS.
G-8
Concentric rings. Dashed-line circles depicted in the plan
view of IAP charts, outside of the reference circle, that show
en route and feeder facilities.
Condensation. A change of state of water from a gas (water
vapor) to a liquid.
Condensation nuclei. Small particles of solid matter in the
air on which water vapor condenses.
Cone of confusion. A cone-shaped volume of airspace
directly above a VOR station where no signal is received,
causing the CDI to fluctuate.
Configuration. This is a general term, which normally refers
to the position of the landing gear and flaps.
Constant-speed propeller. 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.
Continuous flow oxygen system. 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 airliners.
Control and performance. 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. 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. A measure of the response of an aircraft
relative to the pilot’s flight control inputs.
Controllable-pitch propeller (CPP). 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 changing the
direction of shaft revolutions.
Controlled airspace. An airspace of defined dimensions
within which ATC 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. The amount of physical exertion on the
control column necessary to achieve the desired attitude.
Convective weather. Unstable, rising air found in
cumiliform clouds.
Convective SIGMET. Weather advisory concerning
convective weather significant to the safety of all aircraft,
including thunderstorms, hail, and tornadoes.
Conventional landing gear. Landing gear employing a third
rear-mounted wheel. These airplanes are also sometimes
referred to as tailwheel airplanes.
Coordinated flight. Flight with a minimum disturbance of
the forces maintaining equilibrium, established via effective
control use.
COP. See changeover point.
Coriolis illusion. 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.
Coupled ailerons and rudder. 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. The intended direction of flight in the horizontal
plane measured in degrees from north.
Cowl flaps. 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.
Crew resource management (CRM). 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” was 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 current definition includes
all groups routinely working with the flight crew who
are involved in decisions required to operate a flight
safely. These groups include, but are not limited to pilots,
dispatchers, cabin crewmembers, maintenance personnel,
and air traffic controllers. CRM is one way of addressing
the challenge of optimizing the human/machine interface
and accompanying interpersonal activities.