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Tyskland NOTES > Aerodynamic (multiple choice) + drawings > Flashcards

Aerodynamic (multiple choice) + drawings Flashcards

1
Q
  1. Cyclic stick movement:

☐ Alters the tip path plane attitude.

☐ Alters the amount of total rotor thrust.

☐ Changes the coning angle.

☐ Causes an equal blade pitch change on all blades together.

A

☐ Alters the tip path plane attitude.

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2
Q

The rotor thrust is always:

☐ Parallel with the main rotor shaft.

☐ Perpendicular to the plane which contains the swash plate.

☐ Perpendicular to the hub plane.

☐ Perpendicular to the tip path plane.

A

☐ Perpendicular to the tip path plane.

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3
Q

In level flight, as forward speed is increased, induced airflow velocity:

☐ Decreases and the component of the horizontal airflow through the disc decreases.

☐ Increases and the component of the horizontal airflow through the disc decreases.

☐ Increases and the component of the horizontal airflow through the disc increases.

☐ Decreases and the component of the horizontal airflow through the disc increases.

A

☐ Decreases and the component of the horizontal airflow through the disc increases.

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4
Q

What can be noticed during transition from hover to forward flight (anti-clockwise rotor)?

☐ Sudden yawing motion.

☐ Rolling motion to the retreating blade.

☐ Nose-down attitude.

☐ Significant climb without raising the collective pitch lever.

A

☐ Significant climb without raising the collective pitch lever.

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5
Q

Translational lift becomes useful:

☐ As soon as the helicopter moves from a stationary hovering.

☐ Only when the helicopter is operating in-ground-effect.

☐ Only at high all up weights.

☐ As airspeed reaches a value of approximately 20 kts.

A

☐ As airspeed reaches a value of approximately 20 kts.

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6
Q

The coning angle is the angle:

☐ Between the plane of rotation in forward flight and the rotation in the flare.

☐ Between the longitudinal axis of the blade and the horizon.

☐ Between maximum flapping up and maximum flapping down of the blade in autorotation.

☐ Between the longitudinal axis of the blade and the tip path plane.

A

☐ Between the longitudinal axis of the blade and the tip path plane.

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7
Q

Transition to forward flight:

☐ Causes a rolling motion only if the blades are rotating below normal rotor RPM speed.

☐ Causes a roll towards the advancing side.

☐ Causes a roll towards the advancing side only if the blades are rotating anti-clockwise.

☐ Causes a roll towards the retreating side.

A

☐ Causes a roll towards the advancing side.

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8
Q

When the cyclic stick is pushed forward, a main rotor blade will reach its maximum blade pitch angle:

☐ On the retreating side.

☐ In the rearmost position.

☐ On the advancing side.

☐ In the foremost position.

A

☐ On the retreating side.

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9
Q

If the collective pitch lever is raised during straight and level flight, the helicopter will roll to the (1) because (2):

☐ (1) Advancing blade (2) the coning angle decreases.

☐ (1) Advancing blade (2) of the dissymmetry of lift.

☐ (1) Advancing blade (2) the coning angle increases.

☐ (1) Retreating blade (2) of the dissymmetry of lift.

A

☐ (1) Advancing blade (2) the coning angle increases.

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10
Q

A “transition” in a helicopter is:

☐ The force acting on the rotor head in forward flight.

☐ Tilting the disc as a result of cyclic control movement.

☐ A change in the flight condition from or to hovering flight.

☐ The take-off.

A

☐ A change in the flight condition from or to hovering flight.

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11
Q

A helicopter is most likely to encounter vortex ring state under conditions of:

☐ cruising airspeed with power, rate of descent 500ft/min.

☐ a vertical or low airspeed autorotation.

☐ zero airspeed with power; rate of descent less than 200ft/min.

☐ low airspeed with power; rate of descent greater than 300 ft/min.

A

☐ low airspeed with power; rate of descent greater than 300 ft/min.

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12
Q

In a free air hover how does Vi vary along the blade?

☐ It is less at the tip because of tip vortices.

☐ It is less at the tip because of recirculation.

☐ It is greater at the tip because of tip vortices.

☐ It is greater at the root because of the demarcation vortex.

A

☐ It is greater at the tip because of tip vortices.

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13
Q

In a hovering helicopter, recirculated air at the main rotor blade tips will cause:

☐ Increased lift.

☐ Increase in ground effect.

☐ No effect on lift.

☐ A reduction of lift.

A

☐ A reduction of lift.

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14
Q

The effects of recirculation are at their worst:

☐ While making a transition to forward flight.

☐ Over level ground.

☐ Over water.

☐ Close to building-type obstructions.

A

☐ Close to building-type obstructions.

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15
Q

In a constant speed vertical climb outside ground effect, if the effects of parasite drag on the helicopter fuselage are ignored:

☐ Blade pitch angle will be decreased.

☐ Angle of attack must be greater than the blade pitch angle.

☐ Total rotor thrust will need to be greater than aircraft weight.

☐ Total rotor thrust will equal aircraft weight.

A

☐ Total rotor thrust will equal aircraft weight.

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16
Q

The “vortex ring state” which may develop under conditions of a power-on descent at low forward airspeed is:

☐ A stable condition which reduces the rate of descent.

☐ An unstable condition which may result in an uncontrolled rate of descent.

☐ A desirable condition since it causes the helicopter to flare automatically on landing.

☐ Normally controlled by increasing the collective blade pitch angle on the main rotor blades.

A

☐ An unstable condition which may result in an uncontrolled rate of descent.

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17
Q

What is the aerodynamic result when a vertical climb is initiated by raising the collective pitch? Explain by means of the blade element theory:

☐ ↑ AoA ↑ cL ↑ FT ↓ FV ↑ Σ FV ↓ FT ↑ FW → uniform motion

☐ ↓ AoA ↓ cL ↓ FV ↑ FT ↓ FW → uniform motion

☐ ↓ AoA ↓ cL ↑ FT ↓ FV ↓ FT ↓ FT < FW → accelerated motion

☐ ↑ AoA ↑ cL↑ FL ↑ FV ↑ Σ FV ↑ FT ↑ FT > FW → accelerated motion

A

☐ ↑ AoA ↑ cL↑ FL ↑ FV ↑ Σ FV ↑ FT ↑ FT > FW → accelerated motion

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18
Q

The in-ground-effect on a hovering helicopter is greatest on:

☐ Sloping ground with an upslope wind.

☐ Level ground with no wind.

☐ Sloping ground with no wind.

☐ Level ground with a strong wind.

A

☐ Level ground with no wind.

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19
Q

The in-ground-effect is caused by:

☐ Air flowing through the disc creating a divergent (spread out) duct with higher pressure beneath the rotor.

☐ Increasing the mass airflow through the rotor.

☐ High pressure beneath the rotor creating a convergent duct from the downwash.

☐ Recirculation of air through the rotor disc causing air to flow outwards at ground level.

A

☐ Air flowing through the disc creating a divergent (spread out) duct with higher pressure beneath the rotor.

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20
Q

Rotor blade sections are designed so that the center of pressure:

☐ Is normally positioned close to the feathering axis to reduce control system loads.

☐ Can move forward rapidly to aid forward CG and reduce stress related problems at high speeds.

☐ Has a large degree of movement for stability at high and low speeds to reduce stress-related problems.

☐ Move outwards and inwards according to the rotor speed to reduce stress related problems.

A

☐ Is normally positioned close to the feathering axis to reduce control system loads.

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21
Q

The term “washout” means:

☐ That blade pitch angle varies over the span of the blade.

☐ That the used airfoil varies in design (e.g., thickness, camber) from blade root towards blade tip.

☐ The airmass which is accelerated down through the main rotor.

☐ That the blade’s airfoil is constant over the whole length of the blade.

A

☐ That the used airfoil varies in design (e.g., thickness, camber) from blade root towards blade tip.

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22
Q

An increase in angle of attack of a rotor blade would cause an increase in:

☐ Lift only.

☐ Induced drag and a decrease in parasite drag but no change in lift unless rotor speed is increased.

☐ Drag and lift forces.

☐ Induced drag and parasite drag but a reduction in lift.

A

☐ Drag and lift forces.

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23
Q

On a symmetrical blade element with a positive angle of attack lift is produced by:

☐ An increase in flow velocity giving an increase in pressure on the lower surface.

☐ Airflow velocity increasing over upper surface giving decreased pressure and velocity decreasing over lower surface giving increased pressure.

☐ Airflow velocity increasing downward having been deflected by the blade pitch angle and creating an upward pressure on the blade.

☐ An increase in flow velocity on the lower surface and decrease on the upper surface.

A

☐ Airflow velocity increasing over upper surface giving decreased pressure and velocity decreasing over lower surface giving increased pressure.

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24
Q

Rotor blades profile drag is:

☐ A force acting behind the total reaction and at right angles to the relative airflow.

☐ A component of total reaction acting at right angles perpendicular to the relative airflow.

☐ A force proportional to the size of the blade.

☐ A component of total reaction to the aerodynamic forces, acting parallel to the plane of rotation and backward at 90 degrees to total rotor thrust.

A

☐ A component of total reaction to the aerodynamic forces, acting parallel to the plane of rotation and backward at 90 degrees to total rotor thrust.

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25
Q

The amount of lift produced by a given helicopter rotor blade element is dependent upon:

☐ The angle of attack of the blade, the square of the forward speed of the helicopter and the air density.

☐ Angle of attack of the blade, the square of the air velocity relative to the blade element and the air density.

☐ Pitch angle, the square of the forward speed of the helicopter and the square root of the air density.

☐ Angle of attack of the blade, the square root of the relative air velocity to the blade element and the air density.

A

☐ Angle of attack of the blade, the square of the air velocity relative to the blade element and the air density.

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26
Q

The technical term “geometric twist” can be described as:

☐ A reduction in blade angle towards the tip to reduce the chances of Retreating Blade Stall (RBS).

☐ An increase in blade angle towards the tip to delay the onset of compressibility.

☐ A reduction in blade angle towards the tip to delay the onset of compressibility.

☐ A reduction in blade angle towards the tip to give a more equal distribution of lift along the span.

A

☐ A reduction in blade angle towards the tip to give a more equal distribution of lift along the span.

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27
Q

A current requirement for the main rotor blade section is that:

☐ Pitch changes produce large changes in the position of the center of pressure to minimise control forces.

☐ The center of pressure moves rapidly forward as the angle of attack is increased to ensure correct blade flapping.

☐ Changes in angle of attack produce minimum center of pressure movement.

☐ Its induced drag characteristics are insignificant compared with profile drag.

A

☐ Changes in angle of attack produce minimum center of pressure movement.

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28
Q

The total rotor thrust is:

☐ A force acting parallel to the plane of rotation.

☐ A component of total reaction acting at right angles of the aerodynamic forces on the blades, and perpendicular to the plane of rotation.

☐ A force opposite to weight.

☐ A force acting at right angles perpendicular to the relative air flow.

A

☐ A component of total reaction acting at right angles of the aerodynamic forces on the blades, and perpendicular to the plane of rotation.

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29
Q

The resultant force from pressure envelopes around an aerofoil can be described as:

☐ Lift

☐ Rotor thrust

☐ The total reaction

☐ The vertical component of rotor thrust

A

☐ The total reaction

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30
Q

State the drag formula!

☐ FD = cD * 2 * ρ * v² * S

☐ FD = cD * ρ * v² * S

☐ FD = cD * ½ * ρ² * v * S

☐ FD = cD * ½ * ρ * v² * S

A

☐ FD = cD * ½ * ρ * v² * S

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31
Q

cL varies with:

☐ Angle of attack.

☐ Pressure.

☐ Density.

☐ Velocity.

A

☐ Angle of attack.

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32
Q

What is the advantage of a symmetrical aerofoil section as related to helicopter blade design?

☐ The centre of pressure moves little in the normal angle of attack range.

☐ It produces no lift at zero degrees angle of attack.

☐ It has good stalling characteristics.

☐ For a given angle of attack, it has a greater cL than other aerofoil sections.

A

☐ The centre of pressure moves little in the normal angle of attack range.

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33
Q

What is the load factor?

☐ Factor which refers to the extent of thrust that must be decreased to hold altitude while turning.

☐ Factor which refers to the extent of thrust that must be increased to hold altitude while turning.

☐ Factor which refers to the extent of the bank angle that must be decreased to hold while turning.

☐ Ratio of the horizontal part of thrust and the centrifugal force.

A

☐ Factor which refers to the extent of thrust that must be increased to hold altitude while turning.

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34
Q

You are in a trimmed left turn. What happens if you pull collective? (clockwise turning rotor)

☐ Turning radius increases, load-factor decreases.

☐ Turning radius increases, load-factor increases.

☐ Turning radius decreases, load-factor decreases.

☐ Turning radius decreases, load-factor increases.

A

☐ Turning radius decreases, load-factor increases.

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35
Q

The purpose of the swept back tip region in some modern rotor blade designs is to:

☐ Reduce blade tip vortices.

☐ Improve high speed performance.

☐ Reduce blade tip stresses.

☐ Reduce the amount of flapping up.

A

☐ Improve high speed performance.

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36
Q

What happens to the coning angle if rotor RPM decreases and collective pitch is constant?

☐ Nothing.

☐ It increases.

☐ It decreases.

☐ It is balanced by an increase in centrifugal force.

A

☐ It increases.

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37
Q

How does rotor downwash affect a helicopter with horizontal stabilizers (mounted at the tailboom) in a free air hover?

☐ It will pitch nose down.

☐ It will descend.

☐ It will pitch nose up.

☐ The downwash will not affect the stabiliser.

A

☐ It will pitch nose up.

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38
Q

Compared to a straight and level flight, to perform a coordinated turn (same altitude and speed) the collective blade pitch angle (1) and power (2) must be:

☐ (1) Increased (2) increased.

☐ (1) Decreased (2) increased.

☐ (1) Decreased (2) decreased.

☐ (1) Increased (2) decreased.

A

☐ (1) Increased (2) increased.

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39
Q

Which factors have an influence on the bank angle in turning flights?

☐ Weight, velocity, curve radius

☐ Velocity, curve radius, gravity

☐ Mass, velocity, curve radius

☐ Weight, velocity, gravity

A

☐ Velocity, curve radius, gravity

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40
Q

Reverse airflow is associated with:

☐ Very high forward speed only and leads to the formation of shock waves.

☐ Flight at high forward speed and originates at the root of the retreating blade.

☐ The “vortex ring state” and originates at the tip of the advancing blade.

☐ Autorotation and originates at the root of the advancing blade if rotor RPM is allowed to fall.

A

☐ Flight at high forward speed and originates at the root of the retreating blade.

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41
Q

If the collective pitch lever is lowered during straight and level flight, the helicopter will pitch (1) because (2):

☐ (1) Down (2) the coning angle decreases

☐ (1) Up (2) of the dissymmetry of lift

☐ (1) Up (2) of reverse flow at the root of the retreating blade

☐ (1) Down (2) of the dissymmetry of lift

A

☐ (1) Down (2) of the dissymmetry of lift

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42
Q

If the collective pitch lever is raised during straight and level flight, the helicopter will roll to the (1) because (2):

☐ (1) Advancing blade (2) the coning angle decreases

☐ (1) Advancing blade (2) of the dissymmetry of lift

☐ (1) Advancing blade (2) the coning angle increases

☐ (1) Retreating blade (2) of the dissymmetry of lift

A

☐ (1) Advancing blade (2) the coning angle increases

43
Q

When the cyclic stick is pushed forward, a main rotor blade will reach its maximum blade pitch angle:

☐ On the retreating side.

☐ In the rearmost position.

☐ On the advancing side.

☐ In the foremost position.

A

☐ On the retreating side.

44
Q

Retreating blade stall is most likely to occur at:

☐ Vortex ring.

☐ High forward speed, at high gross weight, high altitude and temperature.

☐ Low forward speed with high gross weight.

☐ High gross weight.

A

☐ High forward speed, at high gross weight, high altitude and temperature.

45
Q

The tip path plane is:

☐ The path described by the blade tips during rotation and perpendicular to the plane of rotation.

☐ The path plane described by the blade tips during rotation and perpendicular to the axis of rotation.

☐ The plane perpendicular to the shaft axis of the main rotor.

☐ The path plane described by the disc in forward flight.

A

☐ The path plane described by the blade tips during rotation and perpendicular to the axis of rotation.

46
Q

For a rotor which turns in an anti-clockwise direction seen from above, a sideways hover to the left with zero wind, the pilot will have the advancing blade:

☐ In front of him.

☐ On his left.

☐ On his right.

☐ Behind him.

A

☐ In front of him.

47
Q

For a rotor which turns in a clockwise direction seen from above, in a sideways hover to the right, with zero wind, the pilot will see the retreating blade:

☐ Behind him.

☐ On his right.

☐ On his left.

☐ In front of him.

A

☐ Behind him.

48
Q

For a rotor which turns in a clockwise direction seen from above, in a backward hover, with zero wind, the pilot will see the retreating blade:

☐ Behind him.

☐ On his right.

☐ On his left.

☐ In front of him.

A

☐ On his left.

49
Q

How does an airfoil generate lift?

☐ Air flows across a lower surface of the airfoil because of the low pressure region lift is the action force.

☐ Air flows across a curved upper surface and is accelerated → a low pressure region is formed; ⊥ to the relative wind → lift is the reaction.

☐ Air particles are separated at the stagnation point and must meet again at the rear stagnation point → the upper particles must be faster → lift is produced.

☐ Air flows across a lower surface of an airfoil and is accelerated lift is produced because of the increased dynamic pressure.

A

☐ Air flows across a curved upper surface and is accelerated → a low pressure region is formed; ⊥ to the relative wind → lift is the reaction.

50
Q

The angle of attack of a helicopter rotor blade is defined as the angle between the:

☐ Blade’s chord line and the airflow upstream of the helicopter.

☐ Blade’s chord line and the relative airflow.

☐ Bottom surface of the blade and the tip path plane.

☐ Blade’s chord line and the plane of rotation.

A

☐ Blade’s chord line and the relative airflow.

51
Q

State the lift formula!

☐ FL = cL * ρ * v^2 * S

☐ FL = cL * 2 * ρ * v^2 * S

☐ FL = cL * ½ * ρ^2 * v * S

☐ FL = cL * ½ * ρ * v^2 * S

A

☐ FL = cL * ½ * ρ * v^2 * S

52
Q

The lift coefficient of an airfoil section:

☐ Is at its maximum value at that angle of attack giving the maximum lift to drag ratio.

☐ Increases with an increase in angle of attack up to the stall.

☐ Changes with density.

☐ Changes with the velocity of the airflow, squared.

A

☐ Increases with an increase in angle of attack up to the stall.

53
Q

What is the Magnus effect?

☐ Superposition of translational and rotational velocities of a rotating body (e.g., drum) with the result of pressure differences which cause a lift force.

☐ A vortex is created at the leading edge of an airfoil → “lifting vortex” (known as circulation) is produced which causes wake turbulences.

☐ A vortex is created at the trailing edge of an airfoil → “lifting vortex” (known as circulation) is produced because vortices always occur in pairs.

☐ Superposition of translational and rotational velocities of a helicopter rotor which gives an explanation of the generated drag.

A

☐ Superposition of translational and rotational velocities of a rotating body (e.g., drum) with the result of pressure differences which cause a lift force.

54
Q

Which factors determine the magnitude and direction of the relative airflow in a still air hover?

☐ Induced airflow velocity and rotational velocity of the blade element.

☐ Total rotor thrust and rotor drag.

☐ Lift and rotor drag.

☐ Lift and total aerodynamic forces.

A

☐ Induced airflow velocity and rotational velocity of the blade element.

55
Q

The blade pitch angle of a rotor blade element is:

☐ The angle between the chord line and the tip path plane.

☐ The angle between the tip path plane and the relative airflow.

☐ The angular difference between the root and tip of the blade section.

☐ The angle at which the induced flow passes over the blade section.

A

☐ The angle between the chord line and the tip path plane.

56
Q

The chord line of an airfoil section is the line:

☐ Of points equidistant from upper and lower surfaces.

☐ Drawn between the leading and the trailing edges.

☐ Relative to the upstream airflow.

☐ The tangent at the leading edge of the camber line.

A

☐ Drawn between the leading and the trailing edges.

57
Q

The center of pressure of an airfoil element:

☐ Depends on the height of the airfoil element.

☐ Is located in a fixed point in an asymmetric airfoil.

☐ Is the point where the total aerodynamic force is acting.

☐ Depends only on the boundary layer.

A

☐ Is the point where the total aerodynamic force is acting.

58
Q

The centre of pressure of a symmetrical airfoil section is behind the leading edge approximately at the following % of the section chord:

☐ 0.15

☐ 0.35

☐ 0.1

☐ 0.25

A

☐ 0.25

59
Q

The force which acts at right angles to the relative airflow is:

☐ Lift

☐ Drag

☐ Total reaction

☐ Thrust

A

☐ Lift

60
Q

The Centre of Pressure of an aerofoil section is:

☐ Where the largest component of lift is said to be produced.

☐ The point on the chord line through which the resultant of all aerodynamic forces acts.

☐ Where the resultant of all the centrifugal forces acts relative to the shape of the aerofoil.

☐ The point about which the airflow is deflected around the aerofoil.

A

☐ The point on the chord line through which the resultant of all aerodynamic forces acts.

61
Q

The chord line of a blade section is:

☐ A line tangential to the wing surface on the leading edge.

☐ A line equidistant from the upper and lower surface of the blade.

☐ A straight line from leading to trailing edge.

☐ The line of the chord used to determine balance on some smaller helicopters.

A

☐ A straight line from leading to trailing edge.

62
Q

The camber line of a symmetrical airfoil section is:

☐ Curved towards the upper surface.

☐ Common with the chord line.

☐ Curved towards the lower surface.

☐ A circular arc.

A

☐ Common with the chord line.

63
Q

In the case of a symmetrical aerofoil:

☐ There is no downwash at any angle of attack.

☐ Its characteristics make it totally unsuitable for main rotor applications although it is frequently used for tail rotors.

☐ Induced drag will not be generated at any angle of attack due to the symmetrical pressure distribution.

☐ Pitching moment variations due to centre of pressure movement are small.

A

☐ Pitching moment variations due to centre of pressure movement are small.

64
Q

Thickness/chord ratio of an aerofoil section is expressed in percentage of:

☐ Chord

☐ Wingspan

☐ Blade surface

☐ Thickness

A

☐ Chord

65
Q

That point where airflow leaves the surface of an aerofoil is known as:

☐ The separation point

☐ The critical point

☐ The stagnation point

☐ The transition point

A

☐ The separation point

66
Q

What sources of energy are available in case of a double engine failure?

☐ Energy of the electrical generation system.

☐ Energy of the momentum due to the rotor RPM.

☐ Potential energy because of the height, kinetic energy because of airspeed and rotor RPM.

☐ Only potential energy because of the height.

A

☐ Potential energy because of the height, kinetic energy because of airspeed and rotor RPM.

67
Q

In a normal forward autorotation descent, if the collective lever is raised by a small amount, the rotor RPM will (1) and the rate of descent will (2):

☐ (1) Decrease (2) decrease.

☐ (1) Decrease (2) increase.

☐ (1) Increase (2) decrease.

☐ (1) Increase (2) increase.

A

☐ (1) Decrease (2) decrease.

68
Q

What is the effect of an increasing airspeed on the region of driving blade elements during autorotation?

☐ Shifting of the driving blade elements to the advancing blade.

☐ Shifting of the driving blade elements to the retreating blade.

☐ Shifting of the driving blade elements to the front blade.

☐ Shifting of the driving blade elements to the rear blade.

A

☐ Shifting of the driving blade elements to the retreating blade.

69
Q

During an autorotation descent the maximum gliding distance will be obtained at:

☐ The speed associated with the minimum rate of descent.

☐ A speed slightly less than that associated with the minimum rate of descent.

☐ Speed greater than that associated with the minimum rate of descent.

☐ The minimum speed that will sustain rotor RPM.

A

☐ Speed greater than that associated with the minimum rate of descent.

70
Q

The “avoid” areas in a height/velocity diagram (deadman’s curve) define the height/velocity combinations:

☐ From which it is not possible to make a safe autorotation landing.

☐ In which it is not possible to hover out of ground effect.

☐ In which it is only possible to make a transition into forward flight.

☐ From which it is not possible to operate because of engine power limitations.

A

☐ From which it is not possible to make a safe autorotation landing.

71
Q

A tail rotor is fitted to most helicopters to compensate for:

☐ Main rotor torque reaction only.

☐ Main rotor torque reaction when entering an autorotation.

☐ Main rotor torque reaction and give directional control (yaw control).

☐ Lateral drift when in hovering flight.

A

☐ Main rotor torque reaction and give directional control (yaw control).

72
Q

Yawing in a helicopter is the term used to define a rotation:

☐ About the vertical axis.

☐ Which is always about the horizontal axis.

☐ About the lateral axis.

☐ About the longitudinal axis.

A

☐ About the vertical axis.

73
Q

A helicopter having an anti-clockwise rotating main rotor (when seen from above), with power on, will have a natural tendency to drift:

☐ To the right.

☐ In neither direction because transverse forces are in balance.

☐ To the right if the tail rotor is on the left of the aircraft and to the left if it is on the right.

☐ To the left.

A

☐ To the right.

74
Q

Tail rotor drift is corrected by:

☐ Tilting the main rotor disc in the opposite direction to the drift.

☐ Fitting delta three hinges to the tail rotor.

☐ Fitting the tail rotor as a “tractor type” as opposed to a “pusher type.”

☐ Designing the tail rotor to be level with the main rotor.

A

☐ Tilting the main rotor disc in the opposite direction to the drift.

75
Q

In hovering, for a single rotor helicopter whose main rotor turns clockwise from above, the thrust of the main rotor will be mainly vertical but with a slight orientation towards the:

☐ Front or back of the helicopter according to longitudinal balance.

☐ Right or the left according to side balance.

☐ Right.

☐ Left.

A

☐ Right.

76
Q

With a tail rotor positioned lower than the main rotor, a helicopter at the hover will:

☐ Fly left or right side low depending on which side of the helicopter the tail rotor is positioned.

☐ Fly right side low if main rotor rotates anti-clockwise viewed from above.

☐ Maintain a level attitude.

☐ Fly left side low if main rotor rotates anti-clockwise viewed from above.

A

☐ Fly left side low if main rotor rotates anti-clockwise viewed from above.

77
Q

During flight, an increase in main rotor torque will require:

☐ An increase in tail rotor pitch.

☐ A reduction in tail rotor pitch.

☐ A reduction in tail rotor RPM.

☐ No change in tail rotor pitch.

A

☐ An increase in tail rotor pitch.

78
Q

An anti-torque rotor is necessary on:

☐ A dual-rotor helicopter.

☐ An autogyro.

☐ A synchrocopter.

☐ A single rotor helicopter.

A

☐ A single rotor helicopter.

79
Q

Draw: AR, FWD, ADV, DRIVEN

A
80
Q

Draw: AR, FWD, ADV, NEUTRAL

A
81
Q

Draw: AR, FWD, RETR, DRIVEN

A
82
Q

Draw: AR, FWD, RETR, DRIVING

A
83
Q

Draw: AR, FWD, ADV, DRIVING

A
84
Q

Draw: AR, RETR, NEUTRAL

A
85
Q

Draw: FWD, ADV, CLIMB

A
86
Q

Draw: FWD, ADV, DESCENT

A
87
Q

Draw: FWD, ADV

A
88
Q

Draw: FWD, RETR, CLIMB

A
89
Q

Draw: FWD, RETR, DESCENT

A
90
Q

Draw: FWD, RETR

A
91
Q

Draw: HOVER, RETR

A
92
Q

Draw: HOVER, ADV, CLIMB

A
93
Q

Draw: HOVER, ADV

A
94
Q

Draw: HOVER, RETR, CLIMB

A
95
Q

Draw: HOVER, ADV, DESCENT

A
96
Q

Draw: HOVER, RETR, DESCENT

A
97
Q

Draw: HOVER, RETR, DESCENT

A
98
Q

Fill in the blanks:

A

Vx
Best angle of climb

99
Q

Fill in the blanks:

A

Vy
Best rate of climb

100
Q

Fill in the blanks:

A

Vmax
Maximum Velocity

101
Q

Fill in the blanks:

A

Max range
Airspeed
Power

102
Q

Fill in the blanks:

A

Engine power available (AEO)
Rotor power available (AEO
Rotor power available (OEI)
Total power required

103
Q

FINAL TEST - FILL IN THE BLANKS:

A

CORRECT

Tyskland NOTES (24 decks)

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