Jeppesen Ch 3 Flashcards
1
Q
Lift
A
The force created by the effect of airflow as it passes over and under the wing
2
Q
Weight
A
The force caused by the downward pull of gravity
3
Q
Thrust
A
The forward force that propels the airplane through the air
4
Q
Drag
A
The backward, retarding force that limits the speed of the airplane
5
Q
Newton’s Three Laws Of Motion
A
First: Inertia
Second: F = ma
Third: For every action there is an equal and opposite reaction
6
Q
Bernoulli’s Principle
A
As the velocity of a fluid increases, its pressure decreases
7
Q
Venturi
A
A tube that is narrower in the middle than at the ends
8
Q
Airfoil
A
Any surface, such as a wing, that provides aerodynamic force when it interacts with a moving stream of air
9
Q
Leading Edge
A
The part of an airfoil which meets the airflow first
10
Q
Trailing Edge
A
The portion of an airfoil where the airflow over the upper surface rejoins the lower surface airflow
11
Q
Upwash
A
The deflection of the oncoming airstream upward and over the wing
12
Q
Downwash
A
The downward deflection of the airstream as it passes under the wing and past the trailing edge
13
Q
Relative Wind
A
The airflow which is parallel and opposite the flight path of the airplane
14
Q
Camber
A
The characteristic curve of the airfoil’s upper and lower surfaces
15
Q
Chord Line
A
An imaginary straight line drawn through the airfoil from the leading edge to the trailing edge
16
Q
Angle of Attack
A
The angle between the chord line of the airfoil and the direction of the relative wind
17
Q
Coefficient of Lift
A
A measure of lift as it relates to angle of attack
18
Q
Stall
A
Loss of lift caused by the separation of airflow from the wing’s upper surface
19
Q
Critical Angle of Attack
A
The angle of attack at which a given airplane will stall
20
Q
Aspect Ratio
A
The relationship between the length and width of a wing (span, wingtip to wingtip, divided by average chord). Higher aspect ratios generally correspond to higher lifting efficiency
21
Q
Planform
A
The shape of an airplane’s wing when viewed from above or below
22
Q
Angle of Incidence
A
The angle between the wing chord line and a line parallel to the longitudinal axis of the airplane
23
Q
Stall Strips
A
Metal strips attached to the leading edge of each wing near the fuselage, designed to ensure that the interior portion of the wing stalls before the wingtips, increasing ability to control the airplane during a stall
24
Q
Flaps
A
Devices on the trailing edge of a wing which can be used by the pilot to increase the lifting efficiency of the wing and decrease stall speed
25
Configuration
The position of the landing gear and flaps
26
Plain Flap
Flaps which operate by hinging downward
27
Split Flap
Flaps which operate by hinging only the lower portion of the wing downward
28
Slotted Flap
Flaps which hinge downward but leave a slot through which air from beneath the wing can travel to go over the flap
29
Fowler Flap
Flaps attached on a track and roller system, which move both rearward and down when deployed
30
Parasite Drag
Drag caused by any aircraft surface which deflects or interferes with the smooth airflow around the airplane
31
Form Drag
Drag resulting from the turbulent wake caused by the separation of airflow from the surface of a structure
32
Interference Drag
Drag created by airflow around one part of an airplane interacts with the airflow around an adjacent part
33
Skin Friction Drag
Drag caused by the roughness of an airplane's surface
34
Induced Drag
Drag generated by airflow circulation around the wing as it creates lift
35
Wingtip Vortices
Spiral movement of air generated behind wingtips whenever lift is being produced
36
Ground Effect
An increase in lift caused by the interference of the ground on the airflow around the plane, most pronounced when the plane is less than one wingspan from the ground
37
Clean configuration
Flaps are up and landing gear, if retractable, is retracted
38
Which is true about the four forces of flight?
A: During accelerated flight, thrust and drag are equal
B: The four forces are in equilibrium during unaccelerated flight
C: In straight-and-level unaccelerated flight, all four forces are equal
B: The four forces are in equilibrium during unaccelerated flight
39
True or False? As airspeed increases the angle of attack at which an airfoil stalls also increases
False
40
Identify three methods you can use to control lift during flight
- Changing airspeed
- Changing angle of attack
- Using high-lift devices like flaps
41
Will the wing's angle of attack increase or decrease when you lower trailing edge flaps?
Increase
42
Is it more desirable for the wing root or wingtips to stall first and why?
Wing root, because a stall at the wingtips will reduce aileron effectiveness and decrease control of the airplane
43
List the three forms of parasite drag
- Form drag
- Interference drag
- Skin friction drag
44
What are some examples of aircraft features that reduce parasite drag?
- Streamlining, such as using fairings or retractable gear
- Minimizing protruding rivet heads
- Applying a glossy, smooth surface to the airplane's surfaces
45
Center of Pressure
A point along the wing chord line where lift is considered to be concentrated, aka Center of Lift
46
CG Range
The area within which the center of gravity can exist without adversely affecting the airplane's controllability and balance
47
Tail-Down Force
The balancing force during most flight conditions which pushes downward on the airplane's tail, aiding in longitudinal stability
48
Dihedral
The upward angle of an airplane's wings with respect to the horizontal, appearing to form a shallow V
49
Sweepback
A design in which a plane's wings are angled back from the fuselage in order to keep the center of lift aft of the CG and reduce wave drag when operating near the speed of sound
50
Keel Effect
The steadying influence exerted by the side area of the fuselage as it reacts to the airflow like the keel of a ship
51
Dutch Roll
A phenomenon in which a plane has stronger dihedral effects than directional stability, causing it to over-correct after yawing/sideslip motions and enter an oscillation that feels like a side-to-side wagging of the plane's tail
52
Spiral Instability
A phenomenon in which a plane has stronger directional stability than lateral stability, causing a sideslip to tend to increase once started, tightening into a spiral
53
Power-Off Stalls
A maneuver which simulates the conditions likely to be encountered during a normal landing approach for practice recovering from stalls that might be encountered during such times
54
Power-On Stalls
A maneuver which simulates the conditions likely to be encountered during takeoff, climb-out, and go-arounds for practice recovering from stalls that might be encountered during such times
55
Accelerated Stalls
A maneuver in which stalls are practiced at higher speeds than those found during landing/takeoff conditions
56
Crossed-Control Stall
An uncoordinated stall most likely to occur when a pilot tries to compensate for overshooting a runway during a turn from base to final while on landing approach
57
Secondary Stall
A stall which occurs before positive control has been attained after another stall, normally caused by poor stall recovery
58
Erect Spin
A spin characterized by a slightly nose down rolling and yawing motion in the same direction, also known as an upright spin
59
Inverted Spin
A spin in which the aircraft is spinning upside down with yaw and roll occurring in opposite directions, most likely during aerobatic maneuvers
60
Flat spin
A spin in which the aircraft simply yaws around its vertical axis with a pitch attitude approximately level with the horizon
61
Incipient Spin
The portion of a spin between the time the airplane stalls and rotation starts and the time at which the stall is fully developed
62
Fully Developed Spin
The point in a spin at which the angular rotation rates, airspeed, and vertical speed become stabilized with a nearly vertical flight path
63
Spin Recovery
The final stage of a spin, in which anti-spin forces overcome pro-spin forces, resulting in a slowing and eventual cessation of rotation coupled with a decrease in angle of attack below the spin threshold
64
In relation to the center of gravity, in which direction would the center of pressure normally move as angle of attack is increased on a cambered wing?
Forward
65
Does the propwash resulting from high power settings increase or decrease the contribution of wing dihedral to the lateral stability of an airplane?
Decrease
66
An aircraft with strong directional stability and weak lateral stability is prone to what type of undesirable side effect?
Spiral instability
67
True or False? When landing in gusty winds, airspeed should be increased above normal to help guard against a stall
True
68
List the basic guidelines for stall recovery
- Decrease angle of attack
- Smoothly apply maximum power
- Adjust power as required
- Maintain coordinated flight while restoring power to a normal level
69
List the basic guidelines for spin recovery
- Move the throttle to idle
- Neutralize the ailerons
- Determine the direction of rotation
- Apply full opposite rudder
- Briskly apply elevator/stabilator to return to level flight
70
Gyroscopic Precession
The reaction when a force is applied to the rim of a rotating disc
71
P-Factor
Asymmetrical thrust generated by a propeller, due to the fact that the descending blade has a greater angle of attack than the ascending blade and therefore is able to generate stronger thrust.
72
Spiraling Slipstream
An effect in which the air passing the plane, pushed by the propeller, spirals around the plane and pushes against one side of the rudder
73
L/Dmax
The specific angle of attack that generates the greatest lift with the least amount of corresponding drag
74
Best Glide Speed
The speed that will give the maximum gliding distance for a particular plane at a given weight
75
Glide Ratio
The distance an airplane will travel forward without power in relation to altitude loss
76
Glide Angle
The angle between the glide path of the aircraft and the horizon
77
Centripetal Force
The horizontal component of lift when banking, which pushes towards the inside of the turn
78
Centrifugal Force
An apparent force which results from the effects of inertia when a plane is turned
79
Adverse Yaw
The tendency of an airplane to yaw towards the outside of a turn, caused by the increased drag on the outside wing, which is moving faster through the air than the inside wing
80
Overbanking Tendency
The tendency of a turning airplane to bank into the turn, due to the increased lift on the outside wing, which is moving faster through the air than the inside wing
81
Rate of Turn
The amount of time it takes a plane to turn a specified number of degrees
82
Radius of Turn
The amount of horizontal distance a plane takes to complete a turn
83
Load Factor
The ratio of the load supported by the airplane's wings to the actual weight of the aircraft and its contents
84
Limit Load Factor
The amount of stress that an airplane can withstand before structural damage or failure occurs
85
V-g Diagram
A graphical depiction of the limit load factors for a variety of airspeeds
86
Design Maneuvering Speed
The maximum speed at which you can use full, abrupt control movement without overstressing the airframe (Va)
87
What is the aerodynamic force which opposes the rearward component of weight in a climb?
Thrust
88
What relative airspeed, power, and angle-of-attack conditions produce the most noticeable left-turning tendencies that are common to single-engine, propeller-driven aircraft?
- Low airspeed
- High power
- High angle of attack
89
Name two design elements that can be used to help offset left-turning tendencies
- Rudder trim tab
- Offset vertical stabilizer
- Horizontally canted engine
90
All else being equal, will two aerodynamically identical aircraft with different weights be able to glide the same distance over the ground?
Yes. Only the time elapsed will vary
91
What causes the airplane to turn?
When control surfaces create a horizontal component of lift, which pushes the airplane sideways relative to the flight path
92
If angle of bank and altitude are held constant, what can be done to increase the rate of turn?
Decrease airspeed
93
True or False? Maneuvering speed increases with a decrease in weight
False
