Airdesign2 Midterms Review

Front 1

What angle is needed for tricycle landing gear from Main wheel to the tail?

Back 1

15 deg

Front 2

T or F:

The reference lines for the balance diagram may fall outside the aircraft itself.

Back 2

True

Front 3

List of all items contained in the weight estimate, as well as their CG locations and moments.

Back 3

Balance Table

Front 4

Other term for Center of Gravity

Back 4

Balance Point

Front 5

2 Reasons for changes in balance during flight

Back 5

1. Fuel and Oil being used up

2. Passenger Cabin - lipat ng upuan in the middle of the flight

Front 6

T or F:

To maintain proper balance, the center of gravity must be within the envelope.

Back 6

True

Front 7

For propeller thrust (Fpr) in condition 1 and 2, which V must be used?

Back 7

VL - maximum level speed

Front 8

For propeller thrust (Fpr) in condition 3 and 4, which V must be used?

Back 8

Vg - gliding speed

Front 9

Net tail load factor (n3) is found by:

Back 9

Summation of moments about the CG.

Front 10

Cmt refers to:

Back 10

Total Moment Coefficient

Front 11

T or F:

The increment in moment is determined from a wind tunnel test

Back 11

False - The total moment coefficient is found using a wind tunnel test

Front 12

If data is not available, Delta Cm value may be assumed equal to:

Back 12

-0.01

Front 13

From the preceeding preliminary design, balancing load on the tail was assumed to act at the ____ point on the mean chord of the horizontal tail.

Back 13

20%

Front 14

At 0.15 of Cs, what is the load distribution?

Back 14

3W (found in Balancing Loads in Flight)

Front 15

How is the loads distributed if Cs is 1.0?

Back 15

0.15 , 0.45 , 0.40

Front 16

Formula for w (loads on fixed surfaces) ___

Back 16

w = total load on fixed surface

/ 1.75 x area of fixed surface

Front 17

____ is the sum of aerodynamic lift and drag forces, as well as concentrated and distributed weight of wing mounted engines, fuel stored, and structural elements.

Back 17

Loads on the wing

Front 18

Also called as Aerodynamic Loads

Back 18

Air loads

Front 19

Forces and moments caused by asymmetry of pressure over the surface of the aircraft

Back 19

Air loads

Front 20

T or F:

Maneuvering loads are resultants of pressure distribution over the surfaces of the skin produced by steady flight, maneuver, or gust conditions.

Back 20

False - Air loads (not maneuver loads)

Front 21

2 sub-categories of Air Loads

Back 21

Maneuvering Loads and Gust Loads

Front 22

Greatest air loads comes from:

Back 22

generation of lift from high-g maneuvers

Front 23

T or F:

At lower speeds, the maximum load factor is limited by the maximum lift available

Back 23

True

Front 24

Worst case load that sets the structural requirement of the aircraft

Back 24

Sizing Criteria

Front 25

Depicts the aircraft limit load factor as a function of airspeed.

Back 25

V-n diagram

Front 26

Maximum lift load factor at stall speed:

Back 26

1.0

Front 27

At the Vn Diagram, this is the slowest speed at which the maximum load factor can be reached without stalling.

Back 27

High AOA

Front 28

At the Vn Diagram, this is the rightmost portion signifiying the maximum q.

Back 28

Dive speed, maximum dynamic pressure q.

Front 29

T or F:

Gust loads cannot exceed maneuver loads

Back 29

False

Front 30

T or F:

When an aircraft is experiencing a gust, the effect is an increase or decrease in angle of attack.

Back 30

True

Front 31

Pilots will ______ in severe gust conditions.

Back 31

Pull g

Front 32

Due to control deflection, the greatest impact is in the effect of:

Back 32

elevator on angle of attack

Front 33

T or F:

Deflection of control surfaces produces additional loads directly on the fuselage.

Back 33

False - directy on the wing or tail structure

Front 34

Other term for Pull up speed

Back 34

Maneuvering Speed

Front 35

Maximum speed at which the pilot is able to fully deflect controls without damaging the aircraft.

Back 35

Va, maneuvering speed, pull up speed (Vp)

Front 36

T or F:

For most aircrafts, the maximum level speed VL is more than the maneuver speed. ____

Back 36

True

Front 37

_____ imposed by maximum aileron deflection while at maximum load factor are critical to the wing structure.

Back 37

Instantaneous Loads

Front 38

T or F:

Flap speed Vf is usually thrice the flaps down stall speed

Back 38

False, twice

Front 39

Required Cn Values for the horizontal tail

Back 39

-0.55 for downward and 0.35 for upward

Front 40

Required Cn Values for the vertical tail

Back 40

0.45

Front 41

Wing Planform Shapes as discussed by the module:

Back 41

Straight

Sweptback

Delta

Semidelta

Front 42

Formula for Ct (Tip chord)

Back 42

Cr x taper ratio

Cr x λ

Front 43

Wing position that is most aerodynamically efficient

Back 43

Mid wing

Front 44

Wing position that is used by most cargo aircrafts

Back 44

High Wing

Front 45

Wing position whose wing tips are less likely to hit the ground

Back 45

High wing

Front 46

When the upper wing is closer to the nose, what type of stagger?

Back 46

Positive stagger

Front 47

When the lower wing is closer to the nose, what type of stagger?

Back 47

Negative Stagger

Front 48

When the upper wing is farther to the nose, what type of stagger?

Back 48

Negative Stagger

Front 49

The vertical distance between 2 wings

Back 49

Gap

Front 50

The ratio between the shorter and longer wing

Back 50

Span Ratio

Front 51

The relative incidence between 2 wings

Back 51

Decalage

Front 52

Wing size affects which characteristics?

Back 52

1. Take off and landing field length

2. Cruise performance

3. Ride through turbulence

4. Weight

Front 53

T or F:

For a short field length, large wing/ high wing loading is required.

Back 53

False - low wing loading

Front 54

T or F:

For short field length, a short wing and low wing loading is required.

Back 54

False - Large wing

Front 55

For flight at high altitudes at low speeds, (small/large) wing is required.

Back 55

Large

Front 56

Wing position in which the fuselage needs stiffening

Back 56

High Wing and Mid wing

Front 57

T or F

A low wing loading translates to high load factor.

Back 57

True

Front 58

T or F

High aspect ratio means increased induced drag

Back 58

False, reduced induced drag (which is why gliders have highbaspect ratios.)

Front 59

T or F

Higher Aspect ratio, Higher Span

Back 59

True

Front 60

the ratio between max thickness and chord

Back 60

Thickness Ratio

Front 61

T or F

Higher thickness ratio means lower profile drag at supersonic speeds.

Back 61

False, Higher profile drag

Front 62

T or F

Sweep angle delays drag divergence effects

Back 62

True

Front 63

T or F

The sweep angle contributes to pitch down characteristics

Back 63

False - pitch up characteristics

Front 64

T or F

Forward swept wing is lighter

Back 64

False, heavier

Front 65

T or F

Sweep angle reduces subsonic lift.

Back 65

True

Front 66

T or F

forward swept wing has inferior stall characteristics to aft swept wing

Back 66

False, superior stall characteristics

Front 67

Wing position which has the least interference drag

Back 67

Mid wing

Front 68

Airplanes have constant sweep problems, _____ solves this.

Back 68

Variable sweep

Front 69

T or F

An aircraft having variable sweep is heavier.

Back 69

True, due to pivot mechanism (more weight)

Front 70

Ratio between Tip chord and Root chord

Back 70

Taper ratio

Front 71

Symbol for Taper Ratio

Back 71

λ

Front 72

T or F

Less taper means more fuel volume

Back 72

True, less taper means wider wing thus more space for fuel.

Front 73

T or F

Smaller tip chord is more conducive to tip stall

Back 73

True

Front 74

T or F

More taper means less weight

Back 74

True, more taper means smaller wing -> less structure -> less weight

Front 75

3 Types of Twist

Back 75

Geometric Twist

Linear Twist

Aerodynamic Twist

Front 76

Type of Twist:

Incidence is proportional to distance from root airfoil

Back 76

Linear Twist

Front 77

Type of Twist:

One type of airfoil is used

Back 77

Geometric Twist

Front 78

Wing position that has a shorter landing gear strut

Back 78

Low wing

Front 79

Type of Twist:

Difference in 0 lift angles of the root and tip airfoil

Back 79

Aerodynamic Twist

Front 80

Also called negative dihedral

Back 80

Anhedral

Front 81

T or F

Anhedral angle allows for more lateral stability

Back 81

False, Dihedral angle

Front 82

T or F

Dihedral angle increases dutch roll stability

Back 82

False, decreases dutch roll stability

Front 83

Opposite of Dihedral

Back 83

Anhedral

Front 84

6 Landing Gear Configurations according to the module

Back 84

Single Main

Taildragger

Quadricycle

Bicycle

Tricycle

Multi-bogey

Front 85

Employed by sailplanes

Back 85

Single Main LG Config

Front 86

Flat attitude for landing and take off

Back 86

Bicycle LG Config

Front 87

In a bicycle landing gear configuration, the CG should be:

Back 87

Aft of the midpoint of the 2 wheels.

Front 88

LG Config with more propeller ground clearance

Back 88

Taildragger (since naka lean backwards siya)

Front 89

Where the wing connects to the fuselage

Back 89

Fairings

Front 90

LG Config that is more prone to ground looping

Back 90

Conventional or Taildragger

Front 91

Taildragger: The angle between the ground and the line from centerpoint of the main wheel to the tail wheel

Back 91

10-15 degrees

Front 92

What CG is considered in longitudinal tip over for Taildragger LGC?

Back 92

Most Forward CG

Front 93

Landing Gear Configuration (LGC) that can be landed with a large crab angle

Back 93

Tricycle

Front 94

What CG is considered in longitudinal tip over for Tricycle LGC?

Back 94

Most Aft CG

Front 95

For Lateral Tip-over Criterion in Tricycle LGC, what is the angle created by the most aft cg and the line perpendicular to the line from the nose wheel to main wheel?

Back 95

55 degrees

Front 96

Taildragger: The angle between the centerpoint of the main wheel and the tail wheel

Back 96

10-15 degrees

Front 97

What angle is needed for tricycle landing gear from Main wheel to the tail?

Back 97

15 deg

Front 98

angle for Lateral ground clearance criterion (Tricycle LGC)

Back 98

more than 5 deg

Front 99

Wing position that is commonly adapted by large commercial air transports

Back 99

Low wing

Front 100

For Lateral Tip-over Criterion in Tricycle LGC, what is the angle created by the most aft cg and the line perpendicular to the line from the nose wheel to main wheel?

Back 100

55 degrees

Front 101

Apat na Number of Wings based on the module Tru

Back 101

Monowing

Biplane

Triplane

Multiplane

Front 102

What angle is needed for tricycle landing gear from Main wheel to the tail?

Back 102

15 deg

Front 103

angle for Lateral ground clearance criterion (Tricycle LGC)

Back 103

more than 5 deg

Front 104

Wing position whose wing tips are less likely to hit the ground

Back 104

High wing

Front 105

When the upper wing is closer to the nose, what type of stagger?

Back 105

Positive stagger

Front 106

When the lower wing is closer to the nose, what type of stagger?

Back 106

Negative Stagger

Front 107

When the upper wing is farther to the nose, what type of stagger?

Back 107

Negative Stagger

Front 108

The vertical distance between 2 wings

Back 108

Gap

Front 109

The ratio between the shorter and longer wing

Back 109

Span Ratio

Front 110

The relative incidence between 2 wings

Back 110

Decalage

Front 111

Wing size affects which characteristics?

Back 111

1. Take off and landing field length

2. Cruise performance

3. Ride through turbulence

4. Weight

Front 112

T or F:

For a short field length, large wing/ high wing loading is required.

Back 112

False - low wing loading

Front 113

T or F:

For short field length, a short wing and low wing loading is required.

Back 113

False - Large wing

Front 114

For flight at high altitudes at low speeds, (small/large) wing is required.

Back 114

Large

Front 115

Wing position in which the fuselage needs stiffening

Back 115

High Wing

Front 116

T or F

A low wing loading translates to high load factor.

Back 116

True

Front 117

T or F

High aspect ratio means increased induced drag

Back 117

False, reduced induced drag (which is why gliders have highbaspect ratios.)

Front 118

T or F

Higher Aspect ratio, Higher Span

Back 118

True

Front 119

the ratio between max thickness and chord

Back 119

Thickness Ratio

Front 120

T or F

Higher thickness ratio means lower profile drag at supersonic speeds.

Back 120

False, Higher profile drag

Front 121

T or F

Sweep angle delays drag divergence effects

Back 121

True

Front 122

T or F

The sweep angle contributes to pitch down characteristics

Back 122

False - pitch up characteristics

Front 123

T or F

Forward swept wing is lighter

Back 123

False, heavier

Front 124

T or F

Sweep angle reduces subsonic lift.

Back 124

True

Front 125

T or F

forward swept wing has inferior stall characteristics to aft swept wing

Back 125

False, superior stall characteristics

Front 126

Wing position which has the least interference dragWin

Back 126

Mid wing

Front 127

Airplanes have constant sweep problems, _____ solves this.

Back 127

Variable sweep

Front 128

T or F

An aircraft having variable sweep is heavier.

Back 128

True, due to pivot mechanism (more weight)

Front 129

Ratio between Tip chord and Root chord

Back 129

Taper ratio

Front 130

Symbol for Taper Ratio

Back 130

λ

Front 131

T or F

Less taper means more fuel volume

Back 131

True, less taper means wider wing thus more space for fuel.

Front 132

T or F

Smaller tip chord is more conducive to tip stall

Back 132

True

Front 133

T or F

More taper means less weight

Back 133

True, more taper means smaller wing -> less structure -> less weight

Front 134

3 Types of Twist

Back 134

Geometric Twist

Linear Twist

Aerodynamic Twist

Front 135

Type of Twist:

Incidence is proportional to distance from root airfoil

Back 135

Linear Twist

Front 136

Type of Twist:

One type of airfoil is used

Back 136

Geometric Twist

Front 137

Wing position that has a shorter landing gear strut

Back 137

Low wing

Front 138

Type of Twist:

Difference in 0 lift angles of the root and tip airfoil

Back 138

Aerodynamic Twist

Front 139

Also called negative dihedral

Back 139

Anhedral

Front 140

T or F

Anhedral angle allows for more lateral stability

Back 140

False, Dihedral angle

Front 141

T or F

Dihedral angle increases dutch roll stability

Back 141

False, decreases dutch roll stability

Front 142

Opposite of Dihedral

Back 142

Anhedral

Front 143

6 Landing Gear Configurations according to the module

Back 143

Single Main

Taildragger

Quadricycle

Bicycle

Tricycle

Multi-bogey

Front 144

Employed by sailplanes

Back 144

Single Main LG Config

Front 145

Flat attitude for landing and take off

Back 145

Bicycle LG Config

Front 146

In a bicycle landing gear configuration, the CG should be:

Back 146

Aft of the midpoint of the 2 wheels.

Front 147

LG Config with more propeller ground clearance

Back 147

Taildragger (since naka lean backwards siya)

Front 148

Where the wing connects to the fuselage

Back 148

Fairings

Front 149

LG Config that is more prone to ground looping

Back 149

Conventional or Taildragger

Front 150

Taildragger: The angle between the centerpoint of the main wheel and the tail wheel

Back 150

10-15 degrees

Front 151

What CG is considered in longitudinal tip over for Taildragger LGC?

Back 151

Most Forward CG

Front 152

Landing Gear Configuration (LGC) that can be landed with a large crab angle

Back 152

Tricycle

Front 153

What CG is considered in longitudinal tip over for Tricycle LGC?

Back 153

Most Aft CG

Front 154

For Lateral Tip-over Criterion in Tricycle LGC, what is the angle created by the most aft cg and the line perpendicular to the line from the nose wheel to main wheel?

Back 154

55 degrees

Front 155

What CG is considered in lateral tip over for Taildragger LGC?

Back 155

Most Forward CG

Front 156

What angle is needed for tricycle landing gear from Main wheel to the tail?

Back 156

15 deg

Front 157

angle for Lateral ground clearance criterion (Tricycle LGC)

Back 157

more than 5 deg

Front 158

T or F

For lateral ground clearance criterion, the tires are fully deflated

Back 158

True

Front 159

Wing position that is commonly adapted by large commercial air transports

Back 159

Low wing

Front 160

LGC that permits a very low cargo floor

Back 160

Quadricycle

Front 161

LGC that is used for extra heavy aircrafts

Back 161

Multi-Bogey

Front 162

Aircraft weight that utilize multi-bogey LGC

Back 162

200-400 kips (kilo pounds)

Front 163

2 Types of Loads on aircraft

Back 163

Ground Loads

Air Loads

Front 164

Loads excerted onto the structure during flight

Back 164

Air loads

Front 165

Loads encountered by the aircraft during movement on the ground

Back 165

Ground Loads

Front 166

2 Further division of loads

Back 166

Surface Loads

Body Forces

Front 167

T or F

Surface loads are loads exerted to the structure during flight by the maneuvers carried out by the aircraft

Back 167

False, surface loads are specific to the surface of the structure

Front 168

T or F

Body forces are loads thag act on the surface of the structure

Back 168

False, Surface loads

Front 169

T or F

Body forces act over the volume of the structure and are generated by gravitational and inertial effects

Back 169

True

Front 170

How to alleviate ground clearance problem of low wing position?

Back 170

Dihedral

Front 171

2 Examples of Surface loads

Back 171

Hydrostatic Loads

Aerodynamic Loads (Air loads)

Front 172

Apat na Number of Wings based on the module Tru

Back 172

Monowing

Biplane

Triplane

Multiplane

Front 173

T or F:

Cantilevered wings are lighter than strutted wings.

Back 173

False, Strutted wings are lighter.

Front 174

The longitudinal offset of 2 wings relative to each other

Back 174

Stagger