AE Test Flashcards
Vector
Quantity that represents direction and magnitude
Displacement
Distance and direction of a body’s movement
Velocity
speed and direction of a body’s motion (rate of change of position
Acceleration
Rate of change of velocity
Force
push or pull exerted on a body
Vectors may be added by
placing the head of the 1st on the tail of the second and drawing the resultant
Mass
quantity of molecular material that comprises an object
volume
the amount of space occupied by an object
Density
Mass per unit volume
Mass/volume=density
Work
done when a force acts on a body and moves it
Work=
Force (F) x the distance of displacement (s)
F x S
Power
is the rate of work done per unit time
P=
W/t
or
F(s/t)
Horsepower
Calculated by dividing power by 550
Weight
the force with which a mass is attracted toward the center of the earth by gravity
Force=
mass x acceleration
Moment
created when force is applied from some distance producing rotation
Moment arm
distance between axis and force
Moment=
force x distance
Energy
scalar measure of a body’s capacity to do work
Total energy=
KE+PE
Potential energy
is the ability of a body to do work because of its position or state of being
Kinetic Energy
ability of a body to do work because of its motion
=1/2 x mVsquared
Newton’s 1st law of motion
Law of Equilibrium
A body at rest stays at rest blah blah
Equilibrium
The lack of acceleration in any direction
newton’s 2nd Law of motion
Law of Acceleration
unbalanced force produces accel in direction of the force proportional to the force and inversely proportional to the mass.
A=F/m
Newton’s 3rd Law
the law of interaction
For each action there is an equal and opposite reaction
Ambient static pressure
measurement of the weight of an air column over a specific area
Air density
total mass of air particle for a given volume
Temperature
measure of the average kinetic energy of the air particles
General gas law
relationship between pressure density temp and constant
Static Pressure
the force that molecules of air exert on each other by their random movement
Dynamic Pressure
measure of impact pressure of a large group of air molecules moving together
Total pressure
sum of static and dynamic pressure
Mass flow continuity in subsonic airflow
A1V1=A2V2
Bernoulli’s equation
describes lift
True Altitude
Actual height above mean sea level
Pressure Altitude
height measured above standard datum plane (actual elevation where barometric pressure is equal to 2992
Density altitude
pressure altitude corrected for temperature deviations from the standard atmosphere
(not used for height ref but gauging aircraft performance)
True airspeed (TAS)
speed at which an aircraft moves through an air mass
Groundspeed (GS)
True airspeed corrected for winds
Indicated Airspeed (IAS)
speed that pilot reads of the airspeed indicator (shows dynamic pressure)
TAS increaases
3 kts for every 1000’
Calibrated airspeed (CAS)
indicated airspeed corrected for indicator or sensing error
Equivalent Airspeed (EAS)
calibrated airspeed corrected for errors caused by compressibility effects.
Airfoil
streamlined shape designed to produce lift as it moves through the air
Mean Camber Line (MCL)
line drawn between leading and trailing edge halfway between the upper and lower surface of the airfoil.
Chordline
infinitely straight line drawn from leading edge to trailing edge. Chord is segment between the two edges
Root chord
chord at wing root
tip chord
chord measured at wingtip
average chord
averages all the chords from root to wingtip
camber
curvature of the mean caber line of an airfoil
symmetric airfoil
has zero camber
Positively cambered airfoil
more cross section above than below the chord
Negatively cambered airfoil
opposite of positive
spanwise flow
flow that travels along wing parallel to leading edge, does not create lift.
chordwise flow
flows at right angle to leading edge and produces lift
pitch attitude
angle between longitudinal axis of plane and horizon
flightpath
apparent movement through an airmass
relative wind
motion of air with respect to the motion of the aircraft, opposite of the flightpath
AOA
angle between the chordline and the relative wind
Angle of incidence
angle of the plane’s longitudinal axis and chordline of its wing.
Dihedral angle
upslope or downslope of the wings when viewed head on
wingspan
distance from wingtip to wingtip
33 feet 5 inches for T-6
Wing area (S)
apparent surface area of the wing.
chord x wingspan
Wing loading (WL)
ratio of aircrafts weight to surface area of wings.
WL= weight/S
Wing Taper
reduction in chord from root to tip
Sweep angle
angle between the quarter chord and a line parallel to the lateral axis.
aspect ratio
ratio of wingspan to average chord
Center of Gravity
point at which all weight is considered to be concentrated
Aerodynamic center
also known as the center of lift and where all aerodynamic forces are acting.
Weight
Force of earths gravity acting on mass of aircraft
Lift
Acts against weight
Aerodynamic force
Thrust
Provided by prop or jet
Drag
acts against thrust
aerodynamic force
Equilbrium
absence of acceleration either angular or linear
8 factors that affect lift
air density, velocity, surface area, AOA, shape of airfoil, aspect ration, viscosity, compressibility
Aerodynamic stwist
decrease in camber from the wing root to wingtip
geometric twist
decrease in angle of incidence from wing root to wing tip
parasite drag
drag not associated with production of lift
increases with increase in velocity
3 types of parasitic drag
form, friction, interference
form drag
result of separation of airflow from a surface and wake created by separation
friction drag
caused by turbulent airflow in the boundary layer
interference drag
mixing air streams between aircraft components such as wing and fuselage
Induced Drag
associated with the production of lift
when velocity increases induced drag decreases
total drag
combination of parasite and induced drag resulting in L/D max
ground effect
greatly reduces induced drag within 1 wingspan of ground
Thrust horsepower
propeller output
shaft horsepower
engine output
thrust required
must be higher than total drag
thrust available
max at PCL 100%
as velocity increases thrust available decreases
thrust excess
occurs when thrust available is greater than thrust required for a particular velocity
power available
amount of power the engine produces at given PCL setting, velocity, and density
Power required
amount of power required to produce the thrust required
weight effects on Pr and Tr for level flight
increase weight shift Pr & Tr curves up and to the right
Altitude effects on Pr and Tr for level flight
increase in altitude the Tr curve shifts right, the Pr curve shifts up and right
Ta and Pa decrease at high alt
Plain flap
hinged portion of the trailing edge of wing
Split flap
plate deflected from lower wing surface creates more drag than plain (used by T-6)
Slotted flap
like plane but opens small slot between flap and wing
Fowler
used on larger aircraft to increase camber and surface area
Leading edge flaps
slats
Flap effects
increase lift, slower takeoff and landing, lower aoa
Minimum takeoff speed
20 %above the power off stall speed
Takeoff distance factors
Weight(greatest factor)
flaps
high density altitude
high hot heavy humid
winds
Max rate climb
most climb per unit time (140KIAS)
Max angle
gain most alt for least distance
slower than best rate
still use 140 KIAS
max endure
max time plane can stay airborne
less than LDmax speed and higher AOA
Max range
how far for given fuel
On LDmax speed and AOA
Cruise factors
Weight= lower endure/range
Altitude= higher alt endure/range
Configuration= gear down low endure/range
Wind= does not affect endurance, can help or hurt range
critical mach
first evidence of local supersonic flow on an airplane
best glide speed
engine out max range speed per 1000’ lost 125 kias
glide range
glide ratio 11:1
glide factors
high alt= greater range
tailwind= increased range
configuration
non feathered prop
weight= fly faster
region of reverse commands
fly slower than LDmax
“behind power curve”
approach speed
1.3 times stall speed
4 turning tendencies
Torque causes left role
P-Factor nose high yaw left nose low yaw right
Slipstream swirl yaw left
gyroscopic precession pitch nose up yaw right
adverse yaw
yaw in direction of down aileron
slip
ball and turn pointer on same side
skid
ball and turn pointer on opposite
limit load factor
greatest load factor plane can sustain without risk of permanent deformation or damage
ultimate load factor
max load factor an aircraft can sustain without structural failure
150% limit load factor
Symmetric
only elevator is defleted
asymmetric limits
when aileron or rudder deflected with elevator
maneuvering speed
speed which full abrupt control movements can cause structural damage
227 KIAS
Static stability
tendency of an object to move toward or away from its original equilibrium
Positive- return to
Negative- move away from
Neutral- oscillations never dampen
stability and maneuverability are
inversely proportional
Dynamic stability
position and measure of displacement of an object after it has been disturbed with respect to time
Positive- oscillations become smaller
negative- get bigger
neutral- never dampen
longitudinal stability
About the lateral axis
CG ahead of AC is stable
CG aft of AC is unstable
slideslip angle
difference between flight path and longitudinal axis
wing impact
advancing wing has more parasite drag pulling it back to equilibrium
directional stability Fuselage impact
negative contributor
Directional stability vertical stabilize
greatest positive contributor
Lateral Static Stability
Dihedral wing is greatest positive contributor
high wing is positive
low wing is negative
wing sweep is positive
vert stabilizer is positive
Direction divergence
continues yaw and increase its sideslip angle in response to small initial sideslip
Spiral divergence
continues to roll and yaw in reaction to initial sideslip resulting in a tight descending spiral
Dutch Roll
caused by strong lateral and weak directional stability
Proverse roll
Tendency for plane to roll in same direction it is yawing
Boundary layer definition
Thin layer of air near surface of airfoil where streamlines demonstrate local retardation due to velocity
Laminar Flow
Primary producer of lift
Turbulent Flow
Produces minimal lift
Adverse pressure gradient
low pressure behind max point of thickness
creates turbulent flow
kinetic energy of the relative wind
Definition of boundary layer separation
point in the streamline where airflow no longer adheres to the airfoil
Definition of stall
flight condition where increase in AOA decreases CL
remains constant for any given airfoil
Stall airspeed
variable based on condition
Pro spin rudder
nose will pitch up
lesser vertical component of drag
initial rotation slows
then increases
anti spin rudder
nose will pitch down
larger vertical component of drag
initial rotation increases
then slows
nose down elevator (accelerated)
maximizes vertical drag
nose pitches down
spin accelerates
nose up elevator (unaccelerated)
minimizes vertical drag
nose pitches up
spin decelerates
progressive spin
maintaining full up elevator and anti-spin rudder
lowering of the nose spin direction reversal
aggravated spin
caused by maintaining pro spin rudder and moving stick forward of neutral
nose down pitch and increased roll rate
right spin
stabilizes at lower pitch
slower with more oscillation
rotation rate increased
left spin
higher pitch
stabilizes faster with less oscillations
rotation rate decreased
ways to detect microburst
formal weather briefs
visual cues
airport alert systems
pireps
