Flight Dynamics
Expert-defined terms from the Executive Certificate in Electric Aircraft Aerodynamics and Propulsion course at London School of International Business. Free to read, free to share, paired with a globally recognised certification pathway.
Flight Dynamics #
Flight dynamics is the study of the motion of aircraft in three #
dimensional space. It involves understanding how aircraft move, react to external forces, and maintain stability and control during flight. Flight dynamics encompass various aspects such as aircraft performance, stability, and control.
Aircraft Performance #
Aircraft performance refers to the capabilities of an aircraft in terms of speed… #
It is essential to understand aircraft performance to ensure safe and efficient flight operations.
Aircraft Stability #
Aircraft stability is the ability of an aircraft to return to its original state… #
Stability is crucial for maintaining control and ensuring safe flight.
Aircraft Control #
Aircraft control involves the manipulation of flight controls to steer the aircr… #
Pilots use control inputs to adjust the aircraft's attitude, altitude, and direction.
Angle of Attack #
The angle of attack is the angle between the chord line of an airfoil and the re… #
It determines the lift and drag forces acting on the aircraft. A higher angle of attack generates more lift but also increases drag.
Roll Axis #
The roll axis is an imaginary line passing through the aircraft's center of grav… #
Rotations around the roll axis result in the aircraft rolling from side to side.
Pitch Axis #
The pitch axis is an imaginary line passing through the aircraft's center of gra… #
Rotations around the pitch axis cause the aircraft to pitch up or down.
Yaw Axis #
The yaw axis is an imaginary line passing through the aircraft's center of gravi… #
Rotations around the yaw axis result in the aircraft yawing left or right.
Longitudinal Stability #
Longitudinal stability refers to the stability of an aircraft in the pitch axis #
It ensures that the aircraft returns to its trimmed angle of attack after being disturbed. Longitudinal stability is essential for maintaining straight and level flight.
Lateral Stability #
Lateral stability refers to the stability of an aircraft in the roll axis #
It ensures that the aircraft returns to its wings-level attitude after being disturbed. Lateral stability is crucial for maintaining coordinated turns and preventing adverse yaw.
Directional Stability #
Directional stability refers to the stability of an aircraft in the yaw axis #
It ensures that the aircraft returns to coordinated flight after being disturbed. Directional stability is necessary for maintaining a straight flight path and preventing sideslip.
Stability Augmentation System (SAS) #
A stability augmentation system is a system that improves the stability and cont… #
It uses sensors and actuators to provide automatic assistance to the pilot in maintaining stability and handling qualities.
Flight Envelope #
The flight envelope is a graphical representation of the safe operating limits o… #
It defines the boundaries within which the aircraft can safely operate without exceeding its structural or aerodynamic limits.
Stall #
A stall occurs when the angle of attack of an airfoil exceeds the critical angle… #
Stalls can result in a loss of control and a rapid descent if not promptly corrected.
Spin #
A spin is a sustained autorotational motion of an aircraft around its vertical a… #
Spins typically occur when an aircraft enters a stalled condition with uncoordinated flight controls. Spins can be dangerous and challenging to recover from.
Ground Effect #
Ground effect is the phenomenon where an aircraft experiences increased lift and… #
Ground effect can affect aircraft performance during takeoff, landing, and low-altitude flight.
Dynamic Stability #
Dynamic stability refers to an aircraft's ability to return to a stable flight c… #
It involves the aircraft's response to control inputs and external disturbances.
Static Stability #
Static stability refers to an aircraft's initial tendency to return to its trimm… #
It is determined by the aircraft's inherent design characteristics and is essential for maintaining stable flight.
Neutral Stability #
Neutral stability occurs when an aircraft neither returns to its original state… #
Neutral stability can make an aircraft challenging to control and require constant pilot intervention.
Positive Stability #
Positive stability occurs when an aircraft returns to its original state after b… #
Positive stability is desirable for maintaining control and ensuring safe flight operations.
Negative Stability #
Negative stability occurs when an aircraft diverges further from its original st… #
Negative stability can lead to uncontrollable flight conditions and necessitate immediate corrective action.
Proverse Stability #
Proverse stability refers to an aircraft's tendency to return to its trimmed con… #
Proverse stability is desirable for maintaining predictable flight characteristics and ease of control.
Adverse Stability #
Adverse stability refers to an aircraft's tendency to return to its trimmed cond… #
Adverse stability can make an aircraft more challenging to control and require careful handling by the pilot.
Flight Test #
Flight testing is the process of evaluating an aircraft's performance, handling… #
Flight tests are essential for validating design assumptions, identifying potential issues, and certifying aircraft for operation.
Flight Simulation #
Flight simulation involves using computer #
based models to replicate the behavior of an aircraft in a simulated environment. Flight simulators are valuable tools for training pilots, testing new aircraft designs, and conducting research.
Control Surface #
A control surface is a movable surface on an aircraft that can be adjusted to co… #
Examples of control surfaces include ailerons, elevators, rudders, and flaps.
Aileron #
An aileron is a hinged control surface on the trailing edge of an aircraft wing… #
Ailerons work in opposition to each other to produce a rolling motion.
Elevator #
An elevator is a hinged control surface on the horizontal stabilizer of an aircr… #
Elevators adjust the aircraft's angle of attack and influence its climb or descent.
Rudder #
A rudder is a hinged control surface on the vertical stabilizer of an aircraft t… #
Rudders help the aircraft maintain coordinated flight and control its heading.
Flap #
A flap is a hinged control surface on the trailing edge of an aircraft wing that… #
Flaps are used during takeoff, landing, and maneuvers to adjust the aircraft's performance.
Spoiler #
A spoiler is a hinged control surface on an aircraft wing that can be raised to… #
Spoilers are used to assist in descent, increase drag, and improve control during landing.
Stabilator #
A stabilator is a single #
piece control surface that combines the functions of an elevator and a horizontal stabilizer. Stabilators move as a single unit to control both pitch and stability.
Fuselage #
The fuselage is the main body of an aircraft that houses the cockpit, passengers… #
The fuselage provides structural support and aerodynamic shape to the aircraft.
Wing #
The wing is the primary lifting surface of an aircraft that generates lift throu… #
Wings come in various shapes and configurations to optimize performance and efficiency.
Empennage #
The empennage is the tail section of an aircraft that includes the vertical stab… #
The empennage provides stability and control in the pitch, roll, and yaw axes.
Engine #
The engine is the power source of an aircraft that produces thrust to propel the… #
Engines can be piston-powered, turboprop, turbojet, or turbofan, depending on the aircraft's design and requirements.
Thrust #
Thrust is the force generated by an aircraft's engines to overcome drag and prop… #
Thrust is essential for achieving and maintaining flight.
Lift #
Lift is the aerodynamic force that opposes the aircraft's weight and enables it… #
Lift is generated by the wings as air flows over them at a higher speed than underneath.
Drag #
Drag is the aerodynamic force that opposes the aircraft's motion through the air #
Drag is caused by air resistance and affects the aircraft's speed, fuel consumption, and overall performance.
Weight #
Weight is the force exerted by gravity on an aircraft's mass #
Weight must be balanced by lift to maintain level flight and control the aircraft's altitude.
Center of Gravity #
The center of gravity is the point at which the aircraft's weight is concentrate… #
The center of gravity affects the aircraft's stability, maneuverability, and performance.
Center of Lift #
The center of lift is the point along the wing's chord line where the lift force… #
The center of lift changes with the angle of attack and influences the aircraft's stability and control.
Center of Thrust #
The center of thrust is the point along the aircraft's longitudinal axis where t… #
The center of thrust affects the aircraft's pitch stability and control.
Center of Pressure #
The center of pressure is the point along the wing's chord line where the lift f… #
The center of pressure changes with the angle of attack and influences the aircraft's stability and control.
Stall Speed #
The stall speed is the minimum airspeed at which an aircraft can maintain level… #
Stall speed varies with the aircraft's weight, configuration, and angle of attack.
Maneuvering Speed #
Maneuvering speed is the maximum speed at which full control deflection can be a… #
Maneuvering speed ensures safe handling during aggressive maneuvers.
Takeoff Speed #
Takeoff speed is the minimum speed at which an aircraft can become airborne duri… #
Takeoff speed depends on the aircraft's weight, configuration, and environmental conditions.
Landing Speed #
Landing speed is the speed at which an aircraft touches down on the runway durin… #
Landing speed is critical for a safe and controlled landing without bouncing or overshooting the runway.
Rate of Climb #
The rate of climb is the vertical speed at which an aircraft can ascend in feet… #
The rate of climb is influenced by the aircraft's power, weight, drag, and aerodynamic efficiency.
Rate of Descent #
The rate of descent is the vertical speed at which an aircraft can descend in fe… #
The rate of descent is controlled by the aircraft's pitch attitude, power setting, and aerodynamic configuration.
Bank Angle #
The bank angle is the angle at which an aircraft is rolled about its longitudina… #
Bank angle affects the aircraft's turn radius, load factor, and rate of turn during a maneuver.
Load Factor #
The load factor is the ratio of the lift force to the aircraft's weight #
Load factor increases with maneuvering and affects the aircraft's structural integrity, stability, and control.
Ground Speed #
Ground speed is the speed of an aircraft relative to the ground #
Ground speed is a combination of the aircraft's airspeed and the wind speed and direction.
Airspeed Indicator #
The airspeed indicator is an instrument that displays the aircraft's speed throu… #
Airspeed is crucial for maintaining safe flight operations and avoiding stalls or overspeed conditions.
Altimeter #
The altimeter is an instrument that indicates the aircraft's altitude above sea… #
Altimeters are essential for navigating, maintaining vertical separation, and avoiding terrain or airspace conflicts.
Heading Indicator #
The heading indicator is an instrument that displays the aircraft's magnetic hea… #
Heading indicators help pilots maintain the desired course, navigate accurately, and control the aircraft's direction.
Vertical Speed Indicator #
The vertical speed indicator is an instrument that shows the aircraft's rate of… #
Vertical speed indicators help pilots maintain a desired altitude and control the aircraft's vertical motion.
Attitude Indicator #
The attitude indicator is an instrument that displays the aircraft's pitch and b… #
Attitude indicators help pilots maintain level flight, perform maneuvers, and recover from unusual attitudes.
Turn Coordinator #
The turn coordinator is an instrument that shows the aircraft's rate of turn and… #
Turn coordinators help pilots maintain coordinated flight, perform turns, and control the aircraft's heading.
Flight Director #
A flight director is an electronic system that provides guidance cues to the pil… #
Flight directors help pilots navigate, manage workload, and fly precise flight profiles.
Autopilot #
An autopilot is a system that automatically controls the aircraft's flight path,… #
Autopilots relieve the pilot of manual control tasks, enhance safety, and improve flight efficiency.
Fly #
by-Wire:
Fly #
by-wire is a flight control system that uses electronic signals to transmit pilot inputs to control surfaces. Fly-by-wire systems offer enhanced control characteristics, redundancy, and flight envelope protection.
Flight Control Laws #
Flight control laws are sets of algorithms that govern the behavior of fly #
by-wire systems based on the aircraft's flight condition. Flight control laws adjust control surface deflections to maintain stability, performance, and safety.
Envelope Protection #
Envelope protection is a feature of fly #
by-wire systems that prevents the aircraft from exceeding its structural or aerodynamic limits. Envelope protection enhances safety and prevents the pilot from entering dangerous flight regimes.
Flight Management System (FMS) #
A flight management system is a computerized avionics system that assists pilots… #
FMS integrates navigation databases, autopilots, and flight instruments to optimize flight efficiency.
Automatic Dependent Surveillance #
Broadcast (ADS-B):
ADS #
B is a surveillance technology that uses GPS to broadcast an aircraft's position, velocity, and intent to other aircraft and air traffic control. ADS-B enhances situational awareness, traffic separation, and flight safety.
Electronic Flight Instrument System (EFIS) #
An electronic flight instrument system is a cockpit display system that replaces… #
EFIS provides pilots with integrated flight data, navigation information, and system status.
Primary Flight Display (PFD) #
A primary flight display is a cockpit instrument that presents essential flight… #
PFDs help pilots maintain situational awareness and control the aircraft.
Engine Instrument Display #
An engine instrument display is a cockpit instrument that provides information o… #
Engine displays help pilots monitor engine performance and detect abnormalities.
Multi #
Function Display (MFD):
A multi #
function display is a cockpit instrument that presents various flight information, such as weather, traffic, terrain, and system status. MFDs help pilots manage workload, access critical data, and enhance situational awareness.
Electronic Flight Bag (EFB) #
An electronic flight bag is a tablet or portable device that stores digital char… #
EFBs provide real-time information, reduce paperwork, and improve cockpit efficiency.
Head #
Up Display (HUD):
A head #
up display is a transparent screen that projects flight data onto the pilot's field of view. HUDs allow pilots to view critical information without looking down, enhancing situational awareness and safety.
Flight Data Recorder (FDR) #
A flight data recorder is a device that records essential flight parameters and… #
FDRs are used for accident investigation, safety analysis, and performance monitoring.
Cockpit Voice Recorder (CVR) #
A cockpit voice recorder is a device that records audio communications in the co… #
CVRs capture pilot conversations, radio transmissions, and ambient sounds for accident investigation and analysis.
Flight Management Computer (FMC) #
A flight management computer is an avionics system that calculates and optimizes… #
FMCs assist pilots in managing flight operations, fuel efficiency, and navigation.
Flight Director System (FDS) #
A flight director system is an avionics system that provides guidance cues to th… #
FDS enhances precision, reduces workload, and improves flight safety.
Global Positioning System (GPS) #
The Global Positioning System is a satellite #
based navigation system that provides accurate positioning, velocity, and timing information to aircraft. GPS enhances navigation accuracy, situational awareness, and flight efficiency.
Automatic Terminal Information Service (ATIS) #
ATIS is a continuous broadcast service that provides essential airport and weath… #
ATIS helps pilots prepare for arrival, departure, and approach procedures at an airport.
Transponder #
A transponder is a radio transmitter/receiver that responds to ground #
based radar signals with the aircraft's identification code. Transponders enhance air traffic control surveillance, traffic separation, and aircraft identification.
Mode S Transponder #
A Mode S transponder is an advanced version of the transponder that provides add… #
Mode S transponders enhance air traffic management and situational awareness.
Collision Avoidance System (TCAS) #
A Traffic Collision Avoidance System is an avionics system that provides traffic… #
TCAS enhances flight safety by providing timely warnings and guidance to pilots.
Weather Radar #
Weather radar is an onboard radar system that detects and displays weather patte… #
Weather radar helps pilots avoid hazardous weather conditions and plan safe routes.
Emergency Locator Transmitter (ELT) #
An emergency locator transmitter is a radio beacon that transmits distress signa… #
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