Theory Of Flight Flashcards
0
Q
Components of airplane (5)
A
Fuselage Lifting surfaces Empennage Propulsion system Undercarriage
1
Q
Definition of Airplane
A
Power-driven heavier than air aircraft deriving its lift in flight from aerodynamic reactions on surfaces that remain fixed under given conditions of flight
2
Q
Truss: what forms frame?
A
Longerons and girders
3
Q
Truss principle member
A
Longerons
4
Q
Truss: what takes load
A
Frame
5
Q
Monocoque: describe structure
A
Solid structure, no internal frame, skin takes load
6
Q
Semi-monocoque: what covered with what (describe)
A
Monocoque structure with internal frame/stiffeners (formers, stringers) covered with stressed skin
7
Q
Semi monocoque principle member
A
Formers
8
Q
Semi monocoque: what takes load
A
Formers, stressed skin
9
Q
Monoplane vs biplane
A
One pair wings vs two pairs wings
10
Q
Wing shapes (4)
A
Rectangular Elliptical Delta Tapered
11
Q
Spars run from — to —
A
Wing root to tip
12
Q
Ribs run from — to —
A
Leading edge to trailing edge
13
Q
Compression struts
A
Hold soars in place, take some of load
14
Q
Ailerons allow airplane to
A
Roll
15
Q
MAC
A
Mean aerodynamic chord Average of chord along wing Leading edge to trailing edge
16
Q
Horizontal stabilizer : what stability
A
Longitudinal stability
17
Q
Vertical stabilizer: what stability
A
Directional stability
18
Q
Elevator controls
A
Pitch, longitudinal control
19
Q
Rudder controls
A
Yaw, directional control
20
Q
Stabilator is what?
A
Stabilizer combined with elevator
21
Q
What do trim tabs do
A
Take pressure off flight controls during various phases of flight
22
Q
What is a canard
A
Horizontal stabilizer and lifting surface on nose of aircraft
23
Q
3 types propulsion system
A
Piston powered (common) Turbine engine Jet engine
24
What does landing gear do
Takes shock off landing
25
Rudder controlled by
Foot pedals
26
Elevators and ailerons controlled by
Control stick or control wheel
27
Stress
Force that causes a strain
28
Strain
Distortion of an object due to stress
29
Types of stresses (5)
Shearing (cutting) Bending Tension (stretching) Torsion (twisting) Compression
30
Wing loading
Gross weight / area of lifting surfaces
31
Span loading
Gross weight / span
32
Power loading
Gross weight / engine horsepower
33
Load factor
Live load : dead load (Actual load on wings : aircraft weight on ground)
34
Aircraft journey log : when carried
Always during flight
35
Aircraft journey log: what it records
Daily flight time, air time, fuel, oil, maintenance
36
Aircraft technical log: when is it carried
Not carried on aircraft
37
Aircraft technical log: what does it record
Everything concerning maintenance repairs and modifications
38
What do personal logbooks record
Licenses, training information, flight time, airplane routes
39
Define air time
Starts when wheels leave ground, ends when wheels touch back down
40
Define flight time
Starts when aircraft starts moving under its own power to when it stops, for the purpose of flight
41
Name the four fources
Lift Thrust Weight Drag
42
Lift acts perpendicular to
Relative airflow
43
Camber
Curve of upper and lower surfaces of wing
44
Boundary layer
Thin sheet of air that sticks to wing as it moves through air
45
Parts of boundary layer
Laminar, turbulent , boundary point
46
Relative airflow
Direction of wind flowing relative to wing
47
Angle of attack between
Relative airflow and chord
48
Newtons laws (3)
1. Object in motion stays in motion 2. External force applied to alter state 3. For every action, equal and opposite reaction
49
Down wash
Air hits wing, deflects down Opposite reaction is upward force
50
Bernoulli's principle
Total energy in any system remains constant
51
How is lift created
Top of wing: faster, less pressure Bottom of wing: slower, more pressure
52
Centre of pressure
All distributed pressures act through a line, where line cuts chord
53
When angle of attack increases: lift, drag, c of p
Increases, increases, moves forward
54
After point of stall, c of p
Moves back
55
Weight acts through
Centre of gravity
56
Weight always acts towards
Centre of earth
57
Thrust
Force exerted by engine and its propeller or jet
58
Types of drag (2)
Induced, parasite
59
Parasite drag
Created by parts of airplane not contributing to lift
60
Form drag vs skin drag
How streamlined it is vs tendency of air to cling to surface
61
Induced drag
Caused by parts of airplane active in producing lift
62
Angle of attack and induced drag
Greater = greater
63
Airflow over top of wing flows
Inwards
64
Wing tip vortices
Small eddies formed at training edge, move to tips
65
Ground effect
Vortices reduced close to ground, induced drag decreased
66
Differential ailerons
Up going aileron goes up more than the other goes down
67
Aileron drag
Yaw in opposite direction to which bank applied
68
When thrust and drag are equal and opposite
Aircraft moves forwards at constant speed
69
Equilibrium
Two forces equal and opposite
70
If thrust greater than drag, if drag greater than thrust
Accelerate, decelerate
71
When two forces are equal and opposite but parallel instead of one point
Couple
72
Couples act around
Centre of gravity
73
Conventional airfoil: where thickest, what kind of plane
25% Larger, slower aircraft
74
Laminar flow airfoils
Thickest at 50% Thinner Smaller, faster aircraft
75
Planform
Shape of wing as seen from above
76
Aspect ratio
Ratio of wing span to chord
77
High aspect ratio: lift and induced drag
More lift Less induced drag
78
Angle of incidence between
Wing and longitudinal axis
79
Devices to reduce wing tip vortices (4)
Wing tip tanks Wing tip plates Droop wing tip Winglets
80
Wing fences: appearance, location
Small fin-like surfaces Upper surface of wing
81
What do wing fences do
Control & straighten airflow Reduce wing vortices Reduce induced drag Better slow speed handling and stall characteristics
82
Twist in the wing so wing tip has smaller angle of incidence than wing root
Wash out
83
What is purpose of wash out
Reduces tendency of wing to suddenly stall Wing tips stall last so ailerons remain effective
84
Airfoils on leading edge that pull out at high angle of attacks Improve lateral control by smoothing out turbulent airflow
Slats
85
Leading edge flap
Increase camber and increase lift
86
Devices fitted into wing that increase drag and decrease lift
Spoilers
87
Devices on wing or fuselage that increase drag
Speed brakes
88
Flaps give you:
Better take off performance Steeper approach angles Lower approach/ landing speeds
89
The three axis run through
Centre of gravity
90
Horn balance/ inset hinge
Part of control surface in front of hinge Airflow helps pilot move it
91
Streamlined mass in front of control surface hinge, reduces flutter
Mass balance
92
Tendency of airplane in flight to remain in straight, level, upright flight Return to this attitude if displaced without corrective action by pilot
Stability
93
Stability from design features of an aircraft, affected by weight and c of g
Inherent stability
94
Dynamic vs initial stability
Overall vs initial tendency
95
Neutral vs positive vs negative stability
Continues, returns to original, moves further away
96
Pitch stability is stability about the --- axis
Lateral
97
Longitudinal stability affected by (2)
Horizontal stabilizer, centre of gravity
98
Lateral stability = ---- stability = stability around ----axis
Roll Longitudinal axis
99
Lateral stability affected by (3)
Dihedral Keel effect Sweepback
100
Directional stability = stability about --- axis
Vertical
101
Directional stability affected by (2)
Vertical stabilizer Sweepback
102
Propellor rotates clockwise, therefore roll to left (cause, correction)
Torque Slight right turning tendency built in
103
At high angles of attack and high power setting, descending propellor blade has greater angle of attack than ascending blade, so right side more thrust than left, so yaw to left
Asymmetric thrust, use right rudder
104
When force applied to spinning gyro, force acts as if it was 90 deg in direction of rotation
Precession
105
Cause, correction or precession
Nose up= yaw right Nose down =yaw left Use opposite rudder
106
Propellor pushes air back in corkscrew motion which hits left side of fin
Slipstream
107
cause, correction of slipstream
Constant yaw to left Offset fin, trim, right rudder
108
---- thrust needed at higher altitudes
More
109
Most altitude in least horizontal distance
Best angle of climb (Vx)
110
Most altitude in least time
Best rate of climb (Vy)
111
Resultant of lift and drag, opposes weight
Glide reaction
112
Best endurance speed
Most time in air per altitude lost
113
Best range speed
Furthest distance per altitude lost
114
Angle of bank increase = load factor ----
Increase
115
60 degree bank g's
2 Gs
116
Stall definition
Wing can't produce enough lift to support weight
117
Critical angle of attack= ---- angle
Stall
118
During stall, c of p rapidly moves towards
Trailing edge
119
Aircraft will stall at same --- regardless of altitude
Indicated airspeed
120
Aircraft can stall at any airspeed or altitude if ---- exceeded
Angle of attack
121
Stall and weight
More weight = higher angle of attack
122
Stall and c of g
Forward = high stall speed Rearword = low stall speed
123
Other factors affecting stall
Turns, flaps, aircraft condition
124
Spin definition
Auto rotation which develops after aggravated stall
125
Spiral dive definition
Steep descending turn in which airplane has excessive nose down attitude
126
Spin vs stall
Spin: stalled, speed constant and low Spiral: not stalled, speed increasing
127
V ne
Never exceed speed
128
V no
Normal operating speed
129
V a
Manoeuvring speed (flight controls can be fully deflected)
130
V fe
Max flaps extended speed
131
Mach number
Ratio of speed of body to speed of sound (Mach 1= speed of sound)
132
Pitot tube measures --- pressure How positioned?
Dynamic Clear of slipstream, facing line of sight
133
Static port measures --- pressure
Static
134
What does it do (instrument cases)
Allows them to be same pressure as outside
135
Where is static port located
On side of aircraft, parallel to airflow
136
Altimeter uses what port
Static
137
Vertical speed indicator uses what port
Static
138
Airspeed indicator uses which port
Pitot and static
139
Altimeter: height in meters or feet
Feet
140
Aneroid capsules
Set to standard pressure, capsules expand & contract, moving needle
141
Altimeter errors (3)
Pressure error Temperature error Mountain effect
142
Indicated altitude
What is read off altimeter when set to current pressure
143
Pressure altitude
What is read off altimeter when set to standard pressure
144
Density altitude
Pressure altitude corrected for temperature
145
True altitude
Exact height above MSL
146
Absolute altitude
Actual height above ground
147
Airspeed indicator: airspeed or ground speed
Speed through air
148
How does ASI work
Android capsule inflated with airspeed, moves clockwise Static pressure in case corrects for altitude
149
Airspeed errors (4)
Density Position Lag Icing
150
Airspeeds (3)
Indicated Calibrated True
151
Airspeed marking: red
Never exceed speed
152
Airspeed marking: yellow
Caution range (lower limit Vno)
153
Airspeed marking: green
Normal range (lower limit Vs)
154
Airspeed marking: white
Flaps range (upper limit Vfe lower limit Vso)
155
Variometer
Very sensitive VSI used in gliders to find thermals
156
Gyroscopic inertia
Tendency of rotating body to maintain its plane of motion
157
Precession
When force applied to point on rotating body, body acts as if force applied 90 in direction of spin
158
Heading indicator
Must be corrected every 15 min Operates on principle of guroscopic inertia Indicated heading without errors associated with compass
159
Attitude indicator / artificial horizon
Operated on gyroscopic inertia Used when horizon is obscured by weather
160
Slipping vs skidding
Ball opposite needle vs ball same side as needle
161
Turn and slip indicator
Needle shows direction and rate of turn Operates on gyroscopic precession
162
Turn coordinator
Replaces turn&slip indicator on newer planes Responds to yaw and roll in a turn Operates on gyroscopic precession
163
Magnetic compass accuracy
Only when aircraft is flying straight and level at constant speed
164
Lubber line parallel with, indicates
Longitudinal axis Straight, level, constant airspeed
