LIFT

Question 1

The aerodynamic forces of both lift and drag depend on the combined effect of many variables.
The important factors being:

Answer 1

Dynamic Pressure: The dynamic pressure ( ½ ρ V2) of the airflow is a common denominator of
aerodynamic forces and is a major factor since the magnitude of a pressure distribution depends
on the energy given to the airflow (KE = ½ m V2).
Pressure Distribution: Another major factor is the relative pressure distribution existing on the
surface. The distribution of velocities, with resulting pressure distribution, is determined by the
shape or profile of the surface and the angle of attack (C L or C D).
Surface Area: Since aerodynamic forces are the result of various pressures distributed on a
surface, the surface area (S) is the remaining major factor - the larger the surface area for a given
pressure differential, the greater the force generated.

Question 2

The value of lift divided by drag is a measure of ________. This has a maximum value at one particular angle of attack. For a modern wing this is about ____. If this “optimum” angle of attack is maintained, maximum aerodynamic efficiency will be achieved.
- Maximum CL and minimum CD are not obtained at best L/D. True/ False

Answer 2

The value of lift divided by drag is a measure of aerodynamic efficiency. This has a maximum value at one particular angle of attack. For a modern wing this is about 4°. If this “optimum” angle of attack is maintained, maximum aerodynamic efficiency will be achieved. Note: Maximum CL and minimum CD are not obtained at best L/D. True

Question 3

If speed is increased in level flight by 30% from the minimum level flight speed, we can calculate the new CL as a percentage of C L MAX :

Answer 3

While maintaining level flight at a speed 30% above minimum level flight speed, the CL would be 59% of CL MAX

Question 4

To maintain constant lift if density varies because of altitude change, the TAS must be changed.
• If altitude is increased, density decreases, so ____________.
• If altitude is decreased, density increases, _________________.
Maintaining a constant ______ will compensate for density changes.

Answer 4

To maintain constant lift if density varies because of altitude change, the TAS must be
changed.
• If altitude is increased, density decreases, so TAS must be increased.
• If altitude is decreased, density increases, so TAS must be decreased.
Maintaining a constant IAS will compensate for density changes.

Question 5

To maintain constant lift if speed is changed at a constant altitude (density), the angle of attack must be adjusted.
• If speed is increased, angle of attack must be _______, (if speed is doubled, angle of attack must be decreased to make CL ________ of its previous value).
• If speed is decreased, angle of attack must be _______, (if speed is halved, angle of attack must be increased to make CL _______ its previous value).

Answer 5

To maintain constant lift if speed is changed at a constant altitude (density), the angle of attack must be adjusted.
• If speed is increased, angle of attack must be decreased, (if speed is doubled, angle of attack must be decreased to make CL one quarter of its previous value).
• If speed is decreased, angle of attack must be increased, (if speed is halved, angle of attack must be increased to make CL four times its previous value).

Question 6

The velocity in the force equation is the speed of the aircraft relative to the air through which it is moving - the True Air Speed (TAS).

Answer 6

The velocity in the force equation is the speed of the aircraft relative to the air through which it is moving - _______________

Question 7

When an aircraft is flying at an altitude where the air density is other than sea level ISA, the __must be varied in proportion to ______________. With increasing altitude; the _____ must be _____ to maintain the same _________________.

Answer 7

When an aircraft is flying at an altitude where the air density is other than sea level ISA, the TAS must be varied in proportion to the air density change. With increasing altitude; the TAS must be increased to maintain the same dynamic pressure (Q = ½ ρ V2 ).

Question 8

Air density is a product of ___________________. Humidity reduces air density because _____________.

Answer 8

Air density is a product of static pressure,temperature and humidity. Humidity reduces air density because the density of water vapour is about 5/8 that of dry air.

Question 9

What is Density Altitude ?

Answer 9

On an airfield at sea level with standard pressure, 1013 hPa set in the window will cause the altimeter to read zero. This is the “Pressure Altitude”, which can be very misleading because dynamic pressure depends on the TAS and air density, not just air pressure. If the temperature is above standard, the density of the air will be less, perhaps a lot less, with no direct indication of this fact visible to the pilot. If the temperature is 25°C it would be 10°C above standard (25 - 15 = 10). The air density would be that which would exist at a higher altitude and is given the name, “high density altitude”.
- In practical terms, this means that the aircraft will need a higher TAS for a given dynamic pressure, hence a longer take-off run to achieve the required IAS.

Question 11

Drag is the product of __________________. CD is the ratio of _____________. Drag forces may be expressed in the form of a coefficient which is independent of dynamic pressure and surface area.
D = Q CD S

Answer 11

Drag is the product of dynamic pressure, drag coefficient and surface area. CD is the ratio of drag
per unit wing area to dynamic pressure. drag forces may be expressed in the form of a coefficient which is independent of dynamic pressure and surface area.
D = Q CD S

Question 12

A given aerofoil section will always stall at ___________, but aircraft _______ will influence the IAS at which this occurs.

Answer 12

A given aerofoil section will always stall at the same angle of attack, but aircraft weight will influence the IAS at which this occurs.

Question 13

CL MAX decreases progressively with _______ roughness of the leading edge. Roughness further downstream than ___________ from the leading edge has little effect on CL MAX or the lift-curve slope

Answer 13

CL MAX decreases progressively with increasing roughness of the leading edge. Roughness further downstream than about 20 percent of the chord from the leading edge has little effect on CL MAX or the lift-curve slope

Question 14

Wing Area (S):

Answer 14

The plan surface area of the wing. Although a portion of the area may be covered by fuselage or engine nacelles, the pressure carryover on these surfaces allows legitimate consideration of the entire plan area.

Question 15

Average Chord (c):

Answer 15

The geometric average. The product of the span and the average chord is
the wing area (b x c = S).

Question 16

Aspect Ratio (AR):

Answer 16

The proportion of the span and the average chord (AR = b/c)

Question 17

Taper Ratio (C T / C R)
A rectangular wing has a taper ratio of ____ while the pointed tip delta wing has a taper ratio of ___

Answer 17

The ratio of the tip chord to the root chord. The taper ratio affects the lift distribution and the structural weight of the wing.
- A rectangular wing has a taper ratio of 1.0 while the pointed tip delta wing has a taper ratio of 0.0

Question 18

Sweep Angle

Answer 18

Sweep Angle: Usually measured as the angle between the line of 25% chords and a perpendicular
to the root chord.

Question 19

Mean Aerodynamic Chord (MAC):

Answer 19

The chord drawn through the geographic centre of the plan area. A rectangular wing of this chord and the same span would have broadly similar pitching moment characteristics. The MAC is located on the reference axis of the aircraft and is a primary reference for longitudinal stability considerations.

Question 20

What are the origins of Induced Drag ?

Answer 20

–The stronger the vortices, the greater the reduction in effective angle of attack. Because of this local reduction in effective angle of attack, the overall lift generated by a wing will be below the value that would be generated if there were no spanwise pressure differential.
–To replace the lift lost by the increased downwash, the aircraft must be flown at a higher angle of
attack. This increases drag. This extra drag is called induced drag. The stronger the vortices,
the greater the induced drag.

Question 21

Wake vortex generation begins when the ______________ and continues until the ____________. They present the greatest danger during the ___________ - in other words, at low altitude where large numbers of aircraft congregate.

Answer 21

Wake vortex generation begins when the nosewheel lifts off the runway on take-off and continues until the nosewheel touches down on landing.They present the greatest danger during the take-off, initial
climb, final approach and landing phases of flight - in other words, at low altitude where large
numbers of aircraft congregate.

Question 22

The characteristics of trailing vortices are determined by the “generating” aircraft’s:
 Gross weight - the higher the weight, ____________.
 Wingspan - has an influence ___________.
 Airspeed - the lower the speed, _________________.
 Configuration - vortex strength is greatest with aircraft in ___________ (for a
given speed and weight).
 Attitude - the higher the angle of attack, the _____________.
- There is also evidence that for a given weight and speed a helicopter produces a ______________

Answer 22

The characteristics of trailing vortices are determined by the “generating” aircraft’s:
 Gross weight - the higher the weight, the stronger the vortices.
 Wingspan - has an influence upon the proximity of the two trailing vortices.
 Airspeed - the lower the speed, the stronger the vortices.
 Configuration - vortex strength is greatest with aircraft in a “clean” configuration (for a
given speed and weight).
 Attitude - the higher the angle of attack, the stronger the vortices.
There is also evidence that for a given weight and speed a helicopter produces a stronger vortex than a fixed-wing aircraft.

Question 24

Distribution of Trailing Vortices: Typically the two trailing vortices remain separated by about __________ and in still air they tend to drift slowly downwards and level off, usually between __________________. Behind a large aircraft the trailing vortices can extend as much as __________.

Answer 24

Distribution of Trailing Vortices: Typically the two trailing vortices remain separated by about three
quarters of the aircraft’s wingspan and in still air they tend to drift slowly downwards and level off,
usually between 500 and 1000 ft below the flight path of the aircraft. Behind a large aircraft the trailing
vortices can extend as much as nine nautical miles.

Question 25

Vortex Movement near the Ground: If the generating aircraft is within _____ of the ground, the two vortices will “touch-down” and move outwards at about ____ from the track of the generating aircraft at a height approximately equal to ______ the aircraft’s wingspan.

Answer 25

Vortex Movement near the Ground: Figure 5.17 shows that if the generating aircraft is within 1000 ft of the ground, the two vortices will “touch-down” and move outwards at about 5 kts from the track of the generating aircraft at a height approximately equal to 2 the aircraft’s wingspan.

Question 26

The Decay Process of Trailing vortices: Atmospheric turbulence has the greatest influence on the decay of wake vortices; the stronger the wind, ______________

Answer 26

The Decay Process of Trailing vortices: Atmospheric turbulence has the greatest influence on the decay of wake vortices; the stronger the wind, the quicker the decay.

Question 27

Probability of Wake Turbulence Encounter: Certain separation minima are applied by Air Traffic Control (ATC), but _____________.The majority of serious incidents, close to the ground, occur ____________.

Answer 27

Probability of Wake Turbulence Encounter: Certain separation minima are applied by Air Traffic Control (ATC), but this does not guarantee avoidance.The majority of serious incidents, close to the ground, occur when winds are light.

Question 28

Wake Turbulence Avoidance: Staying ___________ of a preceding or crossing aircraft will usually keep your aircraft out of the generating aircraft’s wake vortex. Unfortunately, deviating from published approach and departure requirements in order to stay above/upwind of the flight path of a preceding aircraft may not be advisable. _______________ remains the best advice for avoiding a wake turbulence encounter.

Answer 28

Wake Turbulence Avoidance:Staying above and/or upwind of a preceding or crossing aircraft will usually keep your aircraft out of the generating aircraft’s wake vortex. Unfortunately, deviating from published approach and departure requirements in order to stay above/upwind of the flight path of a preceding aircraft may not be advisable. Maintaining proper separation remains the best advice for avoiding a wake turbulence encounter.

Question 29

In Ground Effect the Upwash and downwash are ______, causing the effective angle of attack of the wing to _________. Therefore, when an aircraft is “in ground effect” lift will generally be ______ and induced drag (CDi) will be _________. In addition, the reduced downwash will effect both longitudinal stability because of _______, and the ________ because of changes to the effective angle of attack of the tailplane

Answer 29

In Ground Effect the Upwash and downwash are reduced, causing the effective angle of attack of the wing to increase. Therefore, when an aircraft is “in ground effect” lift will generally be increased and induced drag (CDi) will be decreased. In addition, the reduced downwash will effect both longitudinal stability because of CP movement, and the pitching moment because of changes to the effective angle of attack of the tailplane

Question 30

In general, it can be said that a ____ wing aircraft will experience a greater degree of ground effect than an aircraft with a ____ mounted wing.

Answer 30

In general, it can be said that a low wing aircraft will experience a greater degree of ground effect than an aircraft with a high mounted wing.

Question 31

In Ground Effect, type of tailplane camber ____ the pitching moment generated when downwash from the wing changes. Decreased downwash will always result in an aircraft ________. The opposite will be true of increased downwash.

Answer 31

In Ground Effect, type of tailplane camber does not influence the pitching moment generated when downwash from the wing changes. Decreased downwash will always result in an aircraft nose down pitching moment. The opposite will be true of increased downwash.

Question 32

- Air flowing off the wing trailing edge (downwash) cannot be defined as relative airflow because it does not conform to the definitions. Neither is it possible to think strictly of a tailplane angle of attack. - Airflow which has been influenced by the presence of the aircraft (direction of flow and dynamic pressure) must be thought of as _______. And the angle between the chord line and the effective airflow must be thought of as ___________.

Answer 32

- Airflow which has been influenced by the presence of the aircraft (direction of flow and dynamic pressure) must be thought of as Effective Airflow. And the angle between the chord line and the effective airflow must be thought of as Effective Angle of Attack.

Question 33

In Ground Effect- Increasing downwash gives a ______ in tailplane (effective) angle of attack and decreasing downwash gives an _______ in tailplane (effective) angle of attack.

Answer 33

In Ground Effect- Increasing downwash gives a decrease in tailplane (effective) angle of attack and decreasing downwash gives an increase in tailplane (effective) angle of attack.

Question 34

Entering Ground Effect: Consider an aircraft entering ground effect, assuming that a constant CL and IAS is maintained. The decreased downwash will give an ______ in the effective angle of attack, requiring a ____ wing angle of attack to produce the same lift coefficient. If a constant pitch attitude is maintained as ground effect is encountered, ____________ due to the _____ in CL and the _____ in CD i (thrust requirement),

Answer 34

The decreased downwash will give an increase in the effective angle of attack, requiring a smaller wing angle of attack to produce the same lift coefficient. If a constant pitch attitude is maintained as ground effect is encountered, a “floating” sensation may be experienced due to the increase in CL and the decrease in CD i (thrust requirement),

Question 35

Entering Ground Effect- If airspeed is allowed to decay significantly during short finals and the resulting sinkrate arrested by _____________ the angle of attack, upon entering ground effect the wing ____________________.

Answer 35

Entering Ground Effect- If airspeed is allowed to decay significantly during short finals and the resulting sinkrate arrested by increasing the angle of attack, upon entering ground effect the wing could stall, resulting in a heavy landing.

Question 36

Entering Ground Effect- The pilot may need to _____ pitch input (more elevator _____) to maintain the desired landing attitude. This is due to the _____ downwash increasing the ______________. The download on the tail is ________, producing a ____________________.

Answer 36

Entering Ground Effect- The pilot may need to increase pitch input (more elevator back-pressure) to maintain the desired landing attitude. This is due to the decreased downwash increasing the effective angle of attack of the tailplane. The download on the tail is reduced, producing a nose down pitching moment.

Question 37

Entering Ground Effect- Due to the changes in the flowfield around the aircraft there will be a change in position error which may cause the ASI to misread. In the majority of cases, local pressure at the static port will _______ and cause the ASI and altimeter to ________.

Answer 37

Entering Ground Effect- Due to the changes in the flowfield around the aircraft there will be a change in position error which may cause the ASI to misread. In the majority of cases, local pressure at the static port will increase and cause the ASI and altimeter to under read.

Question 38

Three major factors influence production of the required lift force:

Answer 38

Three major factors influence production of the required lift force:  Dynamic Pressure (IAS)  Pressure Distribution (Section profile & Angle of attack)  Wing Area (S)

Question 39

As altitude increases a constant IAS will supply the _______________

Answer 39

As altitude increases a constant IAS will supply the same lift force at a given angle of attack

Question 40

The ___________ ratio is a measure of aerodynamic efficiency.

Answer 40

The Lift/Drag ratio is a measure of aerodynamic efficiency.

Question 41

Contamination of the wing surface, particularly the front ____ of the chord, will seriously decrease aerodynamic performance.

Answer 41

Contamination of the wing surface, particularly the front 20% of the chord, will seriously decrease aerodynamic performance.

Question 42

Why does the cambered aerofoil a significantly higher CL MAX?

Answer 42

When compared to a symmetrical section of the same thickness: at approximately the same stall angle, the cross sectional area of the Astreamtube@ over the top surface is smaller with a more gradual section change. This allows greater acceleration of the air over the top surface, and a bigger pressure differential.

Question 43

For the same angle of attack, why do the symmetrical aerofoil sections generate less lift than the cambered aerofoil section?

Answer 43

Angle of attack is the angle between the chord line and the relative airflow. At the same angle of attack, the cross sectional area of the symmetrical section upper surface Astreamtube@ is larger.

Question 44

Why does the cambered aerofoil section of 12% thickness generate a small amount of lift at slightly negative angles of attack?

Answer 44

At small negative angles of attack, a cambered aerofoil is still providing a reduced cross sectional area Astreamtube@ over the top surface, generating a small pressure differential.

Question 45

What are the disadvantages of the symmetrical aerofoil section of 6% thickness?

Answer 45

It will give a high minimum speed, requiring complex high lift devices to enable the aircraft to use existing runways.

Question 46

To maintain altitude, what must be done as Indicated Air Speed (IAS) is reduced: a. Decrease angle of attack to reduce the drag. b. Increase angle of attack to maintain the correct lift force. c. Deploy the speed brakes to increase drag. d. Reduce thrust.

Answer 46

B

Question 47

If more lift force is required because of greater operating weight, what must be done to fly at the angle of attack which corresponds to CL MAX: a. Increase the angle of attack. b. Nothing, the angle of attack for CL MAX is constant. c. It is impossible to fly at the angle of attack that corresponds to CL MAX. d. Increase the Indicated Air Speed (IAS).

Answer 47

D

Question 48

Which of the following statements is correct: 1 To generate a constant lift force, any adjustment in IAS must be accompanied by a change in angle of attack. 2 For a constant lift force, each IAS requires a specific angle of attack. 3 Minimum IAS is determined by CL MAX. 4 The greater the operating weight, the higher the minimum IAS. a. 1, 2 and 4 b. 4 only c. 2, 3 and 4 d. 1, 2, 3 and 4

Answer 48

D

Question 49

What effect does landing at high altitude airports have on ground speed with comparable conditions relative to temperature, wind, and aeroplane weight: a. Higher than at low altitude. b. The same as at low altitude. c. Lower than at low altitude. d. Dynamic pressure will be the same at any altitude.

Answer 49

A

Question 50

What flight condition should be expected when an aircraft leaves ground effect: a. A decrease in parasite drag permitting a lower angle of attack. b. An increase in induced drag and a requirement for a higher angle of attack. c. An increase in dynamic stability. d. A decrease in induced drag requiring a smaller angle of attack.

Answer 50

B

Question 51

What will be the ratio between airspeed and lift if the angle of attack and other factors remain constant and airspeed is doubled. Lift will be: a. Two times greater. b. Four times greater. c. The same. d. One quarter.

Answer 51

B

Question 52

What true airspeed and angle of attack should be used to generate the same amount of lift as altitude is increased: a. A higher true airspeed for any given angle of attack. b. The same true airspeed and angle of attack. c. A lower true airspeed and higher angle of attack. d. A constant angle of attack and true air speed.

Answer 52

A

Question 53

How can an aeroplane produce the same lift in ground effect as when out of ground effect: a. A lower angle of attack. b. A higher angle of attack. c. The same angle of attack. d. The same angle of attack, but a lower IAS.

Answer 53

A

Question 54

By changing the angle of attack of a wing, the pilot can control the aeroplane’s: a. Lift and airspeed, but not drag. b. Lift, gross weight, and drag. c. Lift, airspeed, and drag. d. Lift and drag, but not airspeed.

Answer 54

C

Question 55

Which flight conditions of a large jet aeroplane create the most severe flight hazard by generating wingtip vortices of the greatest strength: a. Heavy, slow, gear and flaps up. b. Heavy, fast, gear and flaps down. c. Heavy, slow, gear and flaps down. d. Weight, gear and flaps make no difference.

Answer 55

A

Question 56

Hazardous vortex turbulence that might be encountered behind large aircraft is created only when that aircraft is: a. Using high power settings. b. Operating at high airspeeds. c. Developing lift. d. Operating at high altitude.

Answer 56

C

Question 57

Wingtip vortices created by large aircraft tend to: a. Rise from the surface to traffic pattern altitude. b. Sink below the aircraft generating the turbulence. c. Accumulate and remain for a period of time at the point where the takeoff roll began. d. Dissipate very slowly when the surface wind is strong.

Answer 57

B

Question 58

How does the wake turbulence vortex circulate around each wingtip, when viewed from the rear: a. Inward, upward, and around the wingtip. b. Counterclockwise. c. Outward, upward, and around the wingtip. d. Outward, downward and around the wingtip.

Answer 58

C

Question 59

Which statement is true concerning the wake turbulence produced by a large transport aircraft: a. Wake turbulence behind a propeller‑driven aircraft is negligible because jet engine thrust is a necessary factor in the formation of vortices. b. Vortices can be avoided by flying 300 feet below and behind the flightpath of the generating aircraft. c. The vortex characteristics of any given aircraft may be altered by extending the flaps or changing the speed. d. Vortices can be avoided by flying downwind of, and below the flight path of the generating aircraft.

Answer 59

C

Question 60

What effect would a light crosswind have on the wingtip vortices generated by a large aeroplane that has just taken off: a. The downwind vortex will tend to remain on the runway longer than the upwind vortex. b. A crosswind will rapidly dissipate the strength of both vortices. c. A crosswind will move both vortices clear of the runway. d. The upwind vortex will tend to remain on the runway longer than the downwind vortex.

Answer 60

D

Question 61

To avoid the wingtip vortices of a departing jet aeroplane during takeoff, the pilot should: a. Remain below the flightpath of the jet aeroplane. b. Climb above and stay upwind of the jet aeroplane’s flightpath. c. Lift off at a point well past the jet aeroplane’s flightpath. d. Remain below and downwind of the jet aeroplane’s flightpath.

Answer 61

B

Question 62

What wind condition prolongs the hazards of wake turbulence on a landing runway for the longest period of time: a. Light quartering headwind. b. Light quartering tailwind. c. Direct tailwind. d. Strong, direct crosswind.

Answer 62

B

Question 63

If you take off behind a heavy jet that has just landed, you should plan to lift off: a. Prior to the point where the jet touched down. b. At the point where the jet touched down and on the upwind edge of the runway. c. Before the point where the jet touched down and on the downwind edge of the runway. d. Beyond the point where the jet touched down.

Answer 63

D

Question 64

The adverse effects of ice, snow, or frost on aircraft performance and flight characteristics include decreased lift and: a. Increased thrust. b. A decreased stall speed. c. An increased stall speed. d. An aircraft will always stall at the same indicated airspeed.

Answer 64

C

Question 65

Lift on a wing is most properly defined as the: a. Differential pressure acting perpendicular to the chord of the wing. b. Force acting perpendicular to the relative wind. c. Reduced pressure resulting from a laminar flow over the upper camber of an aerofoil, which acts perpendicular to the mean camber. d. Force acting parallel with the relative wind and in the opposite direction.

Answer 65

B

Question 66

Which statement is true relative to changing angle of attack: a. A decrease in angle of attack will increase pressure below the wing, and decrease drag. b. An increase in angle of attack will decrease pressure below the wing, and increase drag. c. An increase in angle of attack will increase drag. d. An increase in angle of attack will decrease the lift coefficient.

Answer 66

C

Question 67

The angle of attack of a wing directly controls the: a. Angle of incidence of the wing. b. Distribution of pressures acting on the wing. c. Amount of airflow above and below the wing. d. Dynamic pressure acting in the airflow.

Answer 67

B

Question 68

In theory, if the angle of attack and other factors remain constant and the airspeed is doubled, the lift produced at the higher speed will be: a. The same as at the lower speed. b. Two times greater than at the lower speed. c. Four times greater than at the lower speed. d. One quarter as much.

Answer 68

C

Question 69

An aircraft wing is designed to produce lift resulting from a difference in the: a. Negative air pressure below and a vacuum above the wing’s surface. b. Vacuum below the wing’s surface and greater air pressure above the wing’s surface. c. Higher air pressure below the wing’s surface and lower air pressure above the wing’s surface. d. Higher pressure at the leading edge than at the trailing edge.

Answer 69

C

Question 70

On a wing, the force of lift acts perpendicular to, and the force of drag acts parallel to the: a. Camber line. b. Longitudinal axis. c. Chord line. d. Flightpath.

Answer 70

D

Question 71

Which statement is true, regarding the opposing forces acting on an aeroplane in steady‑state level flight: a. Thrust is greater than drag and weight and lift are equal. b. These forces are equal. c. Thrust is greater than drag and lift is greater than weight. d. Thrust is slightly greater than Lift, but the drag and weight are equal.

Answer 71

B

Question 72

At higher elevation airports the pilot should know that indicated airspeed: a. Will be unchanged, but ground speed will be faster. b. Will be higher, but ground speed will be unchanged. c. Should be increased to compensate for the thinner air. d. Should be higher to obtain a higher landing speed.

Answer 72

A

Question 73

An aeroplane leaving ground effect will: a. Experience a reduction in ground friction and require a slight power reduction. b. Require a lower angle of attack to maintain the same lift coefficient. c. Experience a reduction in induced drag and require a smaller angle of attack d. Experience an increase in induced drag and require more thrust.

Answer 73

D

Question 74

If the same angle of attack is maintained in ground effect as when out of ground effect, lift will: a. Increase, and induced drag will increase. b. Increase, and induced drag will decrease. c. Decrease, and induced drag will increase. d. Decrease and induced drag will decrease.

Answer 74

B

Question 75

Which is true regarding the force of lift in steady, unaccelerated flight: a. There is a corresponding indicated airspeed required for every angle of attack to generate sufficient lift to maintain altitude. b. An aerofoil will always stall at the same indicated airspeed; therefore, an increase in weight will require an increase in speed to generate sufficient lift to maintain altitude. c. At lower airspeeds the angle of attack must be less to generate sufficient lift to maintain altitude. d. The lift force must be exactly equal to the drag force.

Answer 75

A

Question 76

At a given Indicated Air Speed, what effect will an increase in air density have on lift and drag: a. Lift will increase but drag will decrease. b. Lift and drag will increase. c. Lift and drag will decrease. d. Lift and drag will remain the same.

Answer 76

D

Question 77

If the angle of attack is increased beyond the critical angle of attack, the wing will no longer produce sufficient lift to support the weight of the aircraft: a. Unless the airspeed is greater than the normal stall speed. b. Regardless of airspeed or pitch attitude. c. Unless the pitch attitude is on or below the natural horizon. d. In which case, the control column should be pulled-back immediately.

Answer 77

B

Question 78

Given That: Aircraft A. Wingspan: 51 m Average wing chord: 4 m Aircraft B. Wingspan: 48 m Average wing chord: 3.5 m Determine the correct aspect ratio and wing area. a. Aircraft A has an aspect ratio of 13.7, and has a larger wing area than aircraft B. b. Aircraft B has an aspect ratio of 13.7, and has a smaller wing area than aircraft A. c. Aircraft B has an aspect ratio of 12.75, and has a smaller wing area than aircraft A. d. Aircraft A has an aspect ratio of 12.75, and has a smaller wing area than aircraft B.

Answer 78

B

Question 79

Aspect ratio of the wing is defined as the ratio of the: a. Wingspan to the wing root. b. Square of the chord to the wing span. c. Wing span to the average chord. d. Square of the wing area to the span.

Answer 79

C

Question 80

What changes to aircraft control must be made to maintain altitude while the airspeed is being decreased: a. Increase the angle of attack to compensate for the decreasing dynamic pressure. b. Maintain a constant angle of attack until the desired airspeed is reached, then increase the angle of attack. c. Increase angle of attack to produce more lift than weight. d. Decrease the angle of attack to compensate for the decrease in drag.

Answer 80

A

Question 81

Take-off from an airfield with a low density altitude will result in: a. a longer take-off run. b. a higher than standard IAS before lift off. c. a higher TAS for the same lift off IAS. d. a shorter take off run because of the lower TAS required for the same IAS.

Answer 81

D