AE Flashcards
What is done when a force acts upon a body and moves it?
Work
What is a vector?
A quantity that indicates magnitude and direction
What is force?
A push or pull exerted on a body
F=M(A)
What is mass?
The quantity of molecular material that comprises an object
What is volume?
The amount of space occupied by an object
What is density?
The mass per unit of volume (Mass/Volume)
What is power?
The amount of work done over a period of time (Rate)
What is weight?
The force with which a mass is attracted to the the earth by gravity
What is kinetic energy?
Energy of motion
How many knots TAS will you gain as altitude increases?
3 kts per 1000 feet
What happens to air density and temp as altitude increases?
Both decrease
What atmospheric properties affect pressure?
Temperature and Density
What is total pressure?
Dynamic plus static pressure.
Define True Altitude
Height above sea level (MSL)
Define Pressure Altitude
Height above the standard datum plane. (29.92)
Define Density Altitude
Pressure altitude corrected for temperature
What is the Standard Lapse Rate?
2 °C for every 1000 feet
The measure of the average kinetic energy of air particles is called?
Temperature
Define Static Pressure
The force that air molecules exert upon one another by their random movement
Define Dynamic Pressure
The measure of impact pressure of a large group of air molecules moving together
Define Indicated Airspeed
Airspeed read off the indicator
Define Calibrated Airspeed
Indicated airspeed corrected for indicator errors or minor position errors
Define True Airspeed
The actual speed at which an aircraft moves through an air mass
Define Groundspeed
True Airspeed corrected for winds
Define Equivalent Airspeed
Calibrated airspeed corrected for compressibility effects (negligible for subsonic speeds)
Define Mach Number
TAS/Speed of sound
What is adverse yaw?
The tendency for an aircraft to yaw opposite of a roll
Define Critical Mach Number
Speed with the first evidence of localized supersonic flow
Define Mean Camber Line
The line drawn from the leading edge to the trailing edge of a wing equidistant from the upper and lower surfaces.
Define Wingspan
Length, wingtip to wingtip
Define Chordline
An infinite line drawn straight through the leading and trailing edges
Define Chord
The segment of chordline measured from leading edge to trailing edge
Define Root Chord
Chord measured at the root of the wing
Define Tip Chord
Chord measured at the tip of the wing
Define Wing Area
Wingspan x Average Chord
Define Wing Loading
Weight / Wing Area
Define Aspect Ratio
Wingspan / Average Chord
What is a positively cambered airfoil?
When the Mean Camber Line is above the chord
What is a negatively cambered airfoil?
When the Mean Camber Line is below the chord
What is spanwise flow?
Airflow that travels along the span of the wing, parallel to the leading edge
Define Pitch Attitude
The angle between the longitudinal axis and the horizon (this is NOT the angle of attack)
Define AOA
The angle between the chordline and the relative wind
Define the angle of incidence
The angle between the chordline and the longitudinal axis. Think of it as the angle the wing is mounted to the aircraft
Define dihedral angle
The upward slope of the wings when viewed from head on
Define anhedral angle
The downward slope of the wings when viewed head-on (C-17 wings)
Define relative wind
The apparent motion of air with respect to the motion of the aircraft. Airflow directly opposite of the flight path
What is the T6 wingspan?
33 feet 5 inches
Define wing taper
The reduction in chord length from wing root to tip
Define sweep angle
the angle between a quarter chord and the lateral axis of the airplane
What is the center of gravity?
The point at which all weight is concentrated. It is also the point where all movement on all three axes is MEASURED
What is the aerodynamic center?
The center of lift, the point where all aerodynamic forces are ACTING. (typically aft of CG)
Define aerodynamic force
The result of pressure and friction distributed over an airfoil
What are the two components of aerodynamic force?
Lift and drag
Total drag is comprised of these two types of drag:
Parasitic and Induced
What types of drag makeup parasitic drag?
Form, Friction, and Interference drag
What three factors of lift can a pilot control?
Angle of Attack, Velocity, and Camber (flaps)
What is aerodynamic twist?
A decrease in camber from the wing root to the wing tip. (the reason why stalls develop at the root of a wing)
What is geometric twist?
A decrease in the angle of incidence between the wing root and the wing tip
What is induced drag?
Drag associated with the creation of lift
What is parasitic drag?
Drag NOT associated with the creation of lift
What is form drag?
Drag created by the shape of the wing (difference in static pressures)
What is friction drag?
Drag created by the skin on the aircraft (turbulent airflow at boundary layer)
What is interference drag?
Drag created by the mixing of different component airstreams (think wing root/fuselage connection, gear extension)
What causes ground effect?
Reduction of induced drag due to a decrease in downwash.
When is induced drag the greatest?
Slower airspeeds and high AOA
What drag increases with increased Gs?
Induced
As weight increases, how is equilibrium flight maintained?
AOA or Velocity must increase
Propeller Output is called:
Thrust horsepower
Engine Output is called:
Shaft horsepower
What is propeller efficiency?
The ability to convert shaft horsepower into thrust horsepower
What factors affect thrust available?
PCL setting, Density, and Velocity
Define thrust required (TR)
Thrust needed to overcome drag
Define power required (PR)
The amount of power required to produce thrust required
Define power available
The amount of power an engine is producing given PCL setting, density and velocity
Define power excess
Power available is greater than power required
What type of flaps does the T6 have?
Split
This component of aerodynamic force acts parallel to the relative wind
Drag
What negatively affects takeoff performance?
High, Hot, Heavy, and Humid (altitude, temp, weight, humidity)
Which factor has the greatest effect takeoff performance?
Weight
Vy
Best rate
Vx
Best angle
Best Glide
Max range, power-off airspeed. L/Dmax (125 KIAS)
Max range
Max Distance
Max endurance
Max Time Aloft (white diamond on AOA)
What factors decrease max range and max endurance?
Increased weight, high temp, dirty config, lower altitude
What factors decrease glide range?
Dirty config, lower altitude, headwind, unfeathered prop
Do winds have an effect on Max Endurance?
No
Do winds have an effect on Vy?
No
Do winds have an effect on Vx?
Yes, distance will decreases thus angle is steeper
Do winds have an effect on range?
Yes. Headwinds decrease, tailwinds increase range
What is the T6 glide ratio?
11:1 (11,000 feet horizontal for every 1,000 feet vertical)
What effect does a tailwind have on glide range?
It will increase range
What effect does a headwind have on glide range?
It will decrease range
Does weight have an impact on glide range?
NO. It will change the AOA and airspeed, meaning descent will be faster, but NOT the range.
Where does max range for a propeller aircraft occur?
L/Dmax on the PR curve
Where is the region of reverse command?
Left of Max Endurance on the PR curve
What makes P-factor noticeable?
High power settings and a thrust axis above or below relative wind
In takeoff or climb, P-Factor will yaw the aircraft which direction?
Left
In a descent, P-Factor will yaw the aircraft in which direction?
Right
What direction will torque cause the aircraft to roll?
Left (counterclockwise/opposite of the prop rotation)
Why does slipstream swirl cause the aircraft to turn left?
It increases the AOA of the vertical stab pushing it to the right (nose left)
When is slipstream swirl most noticeable?
High power settings and low airspeed
What causes gyroscopic precession?
Pure Fucking Magic buddy
What causes P-Factor?
One side of the prop is generating more thrust that the other
What causes adverse yaw?
The drag created by the the up wing
Define turn rate
The rate of heading change measured in degrees per second
Name the two factors that affect turn performance
Velocity and Bank Angle
Describe laminar airflow
Area of the boundary layer where air molecules flow smoothly within the streamline
What force opposes and controls the adverse pressure gradient?
the kinetic energy of the relative wind
What is boundary layer separation?
The point in the streamline where airflow no longer adheres to the airfoil
What causes boundary layer separation?
The decreasing ratio of kinetic energy vs. adverse pressure gradient
What is the point of stall on the CL curve?
CLmax
Define a stall
The condition in flight where an increase in AOA results in a decrease in CL
What are the aerodynamic factors associated with increased thrust that impact stall characteristics?
Vertical Thrust Component and Propeller Acceleration Factor
How does the Vertical Thrust Component affect stall characteristics?
It acts in the same direction as lift, lowering stall airspeed
How does the Propeller Acceleration Factor affect stall characteristics?
It increases airflow over the wings (relative wind kinetic energy), lowering stall speed
What direction does roll tend to go in a power-off stall?
Right
What causes a right roll tendency in power-off stalls?
The engine being mounted 1 degree right and 2 degrees down from centerline
What factors affect stall airspeed?
Weight, Altitude, and Load Factor (Gs)
Power-on stalls have a tendency to roll which direction?
Left, primarily due to torque
In what order are controls lost in a stall?
- Aileron
- Elevator
- Rudder
What is the most effective flight control surface in a stall?
Rudder
What is the least effective control surface in a stall?
Aileron
What do leading-edge slats do?
Control how far aft boundary layer separation occurs
When does the stick shaker activate?
15-16 Units AOA, 5-10 Knots above stall speed
Post-stall gyration tendencies are greater when:
Stalls are entered are a higher airspeed
Post-stall gyration tendencies are lower when:
Stalls are entered at a lower airspeed
What are two non-pilot sources of yaw?
Wake turbulence and fuel imbalance
What is autorotation?
Combination of roll and yaw that gets progressively worse due to asymmetrically stalled wings
In a spin which wing will have the higher AOA?
The down-going wing (inside wing)
What two aerodynamic factors affect spins?
Conservation of Angular Momentum (MAIN FACTOR) and acceleration factor
How does anti-spin rudder aid in recovery?
Slows rotation and decreases AOA
What is an accelerated spin?
A spin with the stick anywhere but full aft
What is an unaccelerated spin?
A spin with the stick in full aft
What causes a progressive spin?
Full up elevator with anti-spin rudder (characterized by nose drop and spin reversal)
What causes an aggravated spin?
Forward of neutral stick with pro-spin rudder (characterized by immediate nose down and increased spin rate)
How does decreased weight affect a spin?
Quicker spin entry and recovery, increased oscillations
How does increased weight affect a spin?
Slower spin entry and recovery, less oscillations
Why is a left spin different than a right spin?
Gyroscopic Precession
Gyroscopic Precession RIGHT spin characteristics
Stabilizes at LOWER pitch
Stabilizes SLOWER with MORE oscillation
INCREASED rotation rate
Gyroscopic Precession LEFT spin characteristics
Stabilizes at HIGHER pitch
Stabilizes FASTER with LESS oscillation
DECREASED rotation rate
When do Wingtip Vortices stop?
When the nosewheel touches the ground
What is the minimum spacing for wake turbulence avoidance for LANDING?
2 mins for large aircraft/3 mins for heavy
How fast does wake turbulence sink?
450-500 fpm
How far below an aircraft does wake turbulence level off?
800-900 feet
Contrast a slip vs a skid
Slip = insufficient rudder
Skid = too much rudder
Why must back pressure be added in a turn?
increase total lift, vertical component of lift must equal weight
Why must power be increased in a turn?
Increased AOA means higher induced drag
Define Limit Load factor
Max Load w/o damage (OPS LIMIT)
Define Ultimate Load factor
Max Load w/o FAILURE
Define Manuevering Speed
Max Speed where abrupt controls will not cause damage
Define Asymmetric Gs
Pulling Gs while rolling or yawing
What happens when the stick is full aft in a spin?
Pitch flattens and the rotation rate decreases
What factors affect wingtip vortex strength?
weight, speed, and configuration
When is wake turbulence generated?
Anytime an aircraft is producing lift
What is the minimum spacing for wake turbulence avoidance on TAKEOFF?
2 mins
What is the maximum airspeed adjustment for wind shear?
10 knots
Describe decreasing performance wind shear
Lift/Climb - DECREASE
Airspeed/VSI - DECREASE
Describe increasing performance wind shear
Lift/Climb - INCREASE
Airspeed/VSI - INCREASE
With a 15 knot loss reported, what action do you take?
Flaps - Takeoff
Add 10 knots to airspeed
Anticipate long landing
