Basic Theory Flashcards
Scalar
A quantity that only represents magnitude. ex., time, temp, or volume
Vector
A quantity that represents magnitude and direction. ex., displacement, velocity, acceleration, or force
Mass
The quantity of molecular material that comprises an object
Volume
The amount of space occupied by an object
Density
Mass per unit volume. Expresses weight and force
P=mass/volume
Force
Is mass times acceleration
F=MxA
Weight
Is the force with which a mass is attracted toward the center of the Earth by gravity
Moment
Is created when force is applied from an axis or fulcrum, and tends to produce rotation about that point
Work
Is done when a force acts on a body and moves it.
W=FxS
Power
The rate of doing work
P=W/T
Energy
A scalar measure of the body’s capacity to do work
Potential and kinetic
Conservation energy= energy cannot be created nor destroyed, but transferred from one to another
TE=PE+KE
Potential Energy
The ability of a body to do work because of its position or state of being
PE=weight x height = mgh
Kinetic Energy
The ability of a body to do work because of its motion
KE=1/2 mV^2
Newton’s Law of Equilibrium
A body at rest tends to stay at rest and a body in motion tends to remain in motion in a straight line at a constant velocity unless acted upon by some unbalanced force
The requirements for a plane to be in equilibrium
The sum of all forces AND the sum of all moments around the center of gravity are equal to zero
The requirements for a plane to be in trimmed flight
The sum of all moments around the center of gravity is equal to zero
Newton’s Law of Acceleration
An unbalanced force (F) acting on a body produces an acceleration (a) in the direction of the force that is directly proportional to the force and inversely proportional to the mass (m) of the body
a= F/M
Newton’s Law of Interaction
For every action there is an equal and opposite reaction
Static Pressure
The pressure particles of air exert on adjacent bodies
Air Density
The total mass of air particles per unit of volume
Temperature
A measure of the average random kinetic energy of air particles
Humidity
The amount of water vapor in the air
Viscosity
Is a measure of the air’s resistance to flow and shearing
Local speed of sound
Is the rate at which sound waves travel through a particular air mass
The values of standard atmosphere
A set of reference conditions giving representative values of air properties as a function of altitude
The General Gas Law
The relationships between the three properties of air: pressure, density, and air
PV=nRT
Steady Airflow
Exists if at every point in the airflow static pressure, density, temperature, and velocity remain constant over time
Streamline
Is the path that air particles follow in steady airflow
Streamtube
Streamlines which contains a flow just as effectively as a tube with solid walls
Pressure Altitude
The height above the standard datum plane
Density Altitude
The altitude in the standard atmosphere where the air density is equal to local air density
Indicated Airspeed
The actual instrument indication of the dynamic pressure the airplane is exposed to during flight
IAS
Calibrated Airspeed
When indicated airspeed is corrected for error
CAS
Equivalent Airspeed
Is the true airspeed at sea level on a standard day that produces the same dynamic pressure as the actual flight condition
True Airspeed
Is the actual velocity at which an airplane moves through an air mass
TAS
Ground Speed
The airplanes actual speed over the ground
An Aircraft
Any device used or intended to be used for flight in the air
An Airplane
A mechanically driven fixed-wing aircraft, heavier than air, which is supported by the dynamic reaction of the air against its wings
The five components of an airplane
Engine, landing gear, empennage, fuselage, wing
The airplane three-axis reference system
Lateral (pitch), longitudinal (roll/bank), vertical (yaw)
Chord Line
Is an infinitely long and straight line which passes through its leading and trailing edges
Chord
The precise measurement between the leading and trailing edges measured along the chord lines
Root Chord
The chord at the wing centerline
Tip Chord
The measure at the wingtip
Average Chord
The average of every chord from the wing root to the wingtip
Mean Camber Line
The line halfway between the upper and lower surface of an airfoilIs
Spanwise Flow
Airflow that travels along the span of the wing, parallel to the leading edge
Chordwise Flow
Air flowing at right angles to the leading edge of an airfoil
Pitch Attitude
The angle between an airplane’s longitudinal axis and the horizon
Flight Path
The path described by its center of gravity as it moves through an air mass
Relative Wind
The airflow that the airplane experiences as it moves through the air
Angle of Attack (AoA)
Is the angle between the relative wind and the chord line
Angle of Incidence
Is the angle between the airplane’s longitudinal axis and the chord line of the wing
Dihedral Angle
The angle between the spanwise inclination of the wing and the lateral axis
Its the upward slope of the wing when viewed from the front
wingspan
The length of a wing, measured from wingtip to wingtip
Wing Area
The apparent surface area of a wing from the wingtip to wingtip
Wing Loading
Is the ratio of an airplane’s weight to the surface area of its wings
WL=W/S
Sweep Angle
Is the angle between the lateral axis and a line drawn 25% aft of the leading edge
Aspect Ratio
Is the ratio of the wingspan to the average chord
