Airframes, Aerodynamics, and Theory of Flight Flashcards

Question

Nose Wheel Advantages

Answer 1

- Greater visibility over the nose - Nose over tendencies eliminated - Greater maneuverability on ground

Answer 2

- Less Drag - Cheaper and easier to build and maintain - Will sustain less prop damage - More suitable for ski operations

Answer 3

- Hydraulic leak around main gear (red puddle) - Cracks in the pucks - Rusting over long periods due to lack of use

Answer 4

- Lift acts 90º to wing span - Weight acts at C of G

Answer 5

- Angle of Attack - Velocity of the Airfoil - Density of the Air - Wing Area - Shape of the Aerofoil

Answer 6

- Relative measure of aerofoil's lifting capabilities - Varies with angle of attack and aerofoil type - Higher camber and flaps will yield greater CL - Increases up to critical angle of attack, the decreases rapidly (stall)

Answer 7

Induced Drag + Parasite Drag

Answer 8

- Drag produced by any surface that doesn't contribute to lift - Interference Drag (Joining of two or more parts) - Profile Drag (Form Drag + Skin Friction)

Answer 9

- Drag created by shape of body - Reduce by streamlining

Answer 10

Drag created by tendency of air flowing over a surface to stick to it

Answer 11

Greatest at low airspeeds, clean configuration, heavy

Answer 12

- High Aspect Ratio (Ratio of span to average chord) - Winglets (Reduce airflow around wing tip) - Ground effect

Answer 13

- Different shapes and sizes - Maximum camber is about 25% chord from leading edge

Answer 14

- Maximum camber occurs at 50% chord - Maintains smooth laminar flow over greater percentage of chord - Used on higher speed aircraft - Stalls more violently at high angles of attack

Answer 15

Shape of wing as seen from directly above

Answer 16

Angle at which the wing is permanently inclined to the longitudinal axis of the airplane

Answer 17

- Twist in the wing where the angle of incidence at the root is greater than at the tip - Improves stall characteristics by having wing root stall before wingtips - Enhances aileron control at low speeds

Answer 18

- Strips attached to the leading edge of the wing near the root - Purpose is wing root area to stall first - Very similar to washout

Answer 19

- Fin-like vertical surfaces attached to the upper surface of the wing to prevent spanwise airflow - Wing Fences improve slow-speed handling and stall characteristics

Answer 20

- Long narrow strips arranged spanwise along the top surface of an aerofoil - Purpose of spoilers is to increase drag and spoil lift - Can replace ailerons as a means of roll control

Answer 21

- Metal plates used on high speed aircraft to increase drag withou t decreasing lift - Located near trailing edge of airfoil - Used to slow the aircraft at high speed when unsafe to deploy flaps or landing gear

Answer 22

- Small vertical plates arranged across the upper surface of the wing - Purpose is to re-energize the boundary layer to reduce drag caused by turbulence airflow

Answer 23

- High lift device FIXED to the leading edge of an airfoil - Used to maintain stability and control at low speeds

Answer 24

- High lift device on the leading edge of an airfoil that is RETRACTABLE - Used to maintain stability and control at low speeds

Answer 25

Creates a low pressure area between the wing and the extended flap to create more drag than the plain flap with lesser angles of deflection

Answer 26

Combines camber change with an increase in wing area as well as the creation of a slot to obtain a smooth airflow

Answer 27

Increases wing area without creating the slot

Answer 28

Combines camber changes and slots to obtain smoother airflow

Answer 29

- Tab on trailing edge of control surface - Moves opposite to control surface - Eases amount of force required by pilot

Answer 30

- Tab on trailing edge of control surface - Moves in same direction as control surface - Increases amount of force required by pilot

Answer 31

In rolling the wings, down-going aileron increases the drag on that wing, causing adverse yaw

Answer 32

Up-going aileron projects into airflow, increasing form drag, balancing the induced drag on the down-going aileron

Answer 33

Up-going aileron moves through a greater angle than the down-going aileron, increasing form drag, balancing the induced drag on the down-going aileron

Answer 34

- Aerodynamic Balance (Extending part of control surface in opposing airflow to hold surface in position) - Mass Balance (Placing a mass ahead of the control surface hinge to prevent flutter at high speed)

Answer 35

Initial Tendency to return

Answer 36

Overall tendency to return

Answer 37

- Stability about the lateral axis (or pitch stability) - Influenced by the horizontal stabilizer and C of G position

Answer 38

- Positive Static Stability - More tail-down force required to balance weight ahead of the centre of pressure - Effective weight increases, stall speed increases, TAS decreases

Answer 39

- Less Positive Static Stability - less tail-down force required to balance weight ahead of the centre of pressure - Effective weight decreases, TAS increases

Answer 40

- Neutral Static Stability - No tail down force exerted

Answer 41

- Balancing force is ahead of the C of G - Horizontal stabilizer will always be a positive force - Less apparent weight, higher TAS - aerodynamically efficient, however engine gets disturbed airflow in rear of aircraft - Aft C of G more stable than forward C of G

Answer 42

- Angle that a wing makes with the horizon - Sideslip is produced in a wingdrop - Lower wing meets relative airflow at greater angle of attack - Aircraft will tend to roll back to straight and level

Answer 43

Occurs on high wing aircraft where the weight of the aircraft is primarily below the wing and acts as a pendulum to correct any lateral instability

Answer 44

- Wing drops and creates a sideslip - Leading edge of the lower wing presents itself at an angle perpendicular to the relative airflow - Lower wing will create more lift, causing a roll back to straight and level

Answer 45

- Creates a greater surface area aft of the C of G - Any disturbance from the desired direction is automatically corrected (weather vaning)

Answer 46

When aircraft is yawed, upwind wing has longer leading edge to the relative airflow, creating more drag on that wing, pulling the aircraft back straight

Answer 47

= regular stalls speed * square root of load factor - Load factor = 1/cos(bank)

Answer 48

- Clockwise spinning propeller causes an opposite counter-clockwise rolling action on the airframe - Yaw to the left

Answer 49

- At high angles of attack, down-going propeller meets relative airflow at a greater angle of attack, producing more thrust on the right side of propeller - Yaw to the left

Answer 50

- Propeller acts as a gyro - Any force applied to spinning gyro acts as if that force had been applied from 90º in the direction of rotation - When aircraft pitches down, yaw to the left - Experienced by tail-wheel aircraft when tail wheel rises

Answer 51

- Spiralling corkscrew of air strikes tail on left side - Causes nose to pivot to left when power setting is high - Reduction in power causes yaw to right

Answer 52

Highest altitude at which an aircraft can maintain a 100 fpm climb

Answer 53

Altitude at which an aircraft can no longer climb

Answer 54

- Point on wing where lift is assumed to act - Center of pressure shifts as the angle of attack changes

Answer 55

- Higher the weight, higher the stall speed - Due to more downforce required, therefore increasing effective weight, needing more lift, higher angle of attack

Answer 56

- Will stall at higher airspeed with forward C of G - Aft C of G has higher TAS

Answer 57

Tendency to over-bank

Answer 58

Under banking Tendency