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RA-Aus BAK practice questions

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Question 1Aviation Fundamentals (Learning the Basics of Flight)

Which force directly opposes weight in straight-and-level unaccelerated flight?

  1. Lift Correct answer.
  2. Drag
  3. Thrust
  4. Inertia

Explanation

In steady straight-and-level flight the four forces balance: lift equals weight and thrust equals drag. Lift acts upward through the wing and supports the aircraft's mass. Inertia is not one of the four forces of flight.

Question 2Aviation Fundamentals (Learning the Basics of Flight)

What is the primary purpose of the wing's angle of attack?

  1. To control the amount of lift generated Correct answer.
  2. To reduce the aircraft's total weight
  3. To set the engine power output
  4. To determine the fuel flow rate

Explanation

Angle of attack is the angle between the wing chord line and the relative airflow, and it strongly influences lift. Increasing angle of attack raises lift up to the critical angle. It has no direct effect on weight, power or fuel flow.

Question 3Aviation Fundamentals (Learning the Basics of Flight)

An aircraft stalls when the wing exceeds its critical angle of attack. Which statement best describes this condition?

  1. The wing's angle of attack becomes zero
  2. The engine stops producing power
  3. The aircraft exceeds its maximum speed
  4. The airflow separates and lift decreases sharply Correct answer.

Explanation

A stall occurs when the critical angle of attack is exceeded, causing airflow separation over the wing and a sudden loss of lift. It can happen at any speed and any attitude. Engine power and airspeed are not the defining cause.

Question 4Aviation Fundamentals (Learning the Basics of Flight)

What happens to induced drag as airspeed increases in level flight?

  1. It stays exactly the same
  2. It decreases Correct answer.
  3. It increases
  4. It becomes negative

Explanation

Induced drag is a by-product of lift and is greatest at low speed and high angle of attack. As speed increases the wing needs a smaller angle of attack, so induced drag falls. Parasite drag, by contrast, rises with speed.

Question 5Aviation Fundamentals (Learning the Basics of Flight)

Which of these is a correct description of the aircraft's longitudinal axis?

  1. A line running from wingtip to wingtip
  2. A line drawn along the wing chord
  3. A line running vertically through the centre of gravity
  4. A line running from nose to tail through the centre of gravity Correct answer.

Explanation

The longitudinal axis runs fore and aft through the centre of gravity, and rotation about it is roll controlled by the ailerons. The lateral axis runs wingtip to wingtip and the vertical axis runs through the centre of gravity vertically.

Question 6Aviation Fundamentals (Learning the Basics of Flight)

Which control surface produces roll about the longitudinal axis?

  1. Ailerons Correct answer.
  2. Elevator
  3. Flaps
  4. Rudder

Explanation

Ailerons move in opposite directions on each wing to raise one wing and lower the other, producing roll about the longitudinal axis. The elevator controls pitch and the rudder controls yaw. Flaps increase lift and drag for takeoff and landing.

Question 7Aviation Fundamentals (Learning the Basics of Flight)

In a banked turn, what is the effect of load factor on the stall speed?

  1. Stall speed is unaffected
  2. Stall speed increases Correct answer.
  3. Stall speed decreases
  4. Stall speed becomes zero

Explanation

Banking increases the load factor, which raises the lift required and therefore the stall speed. The stall speed rises in proportion to the square root of the load factor. A steeper bank therefore gives a higher stall speed.

Question 8Aviation Fundamentals (Learning the Basics of Flight)

What is the main function of dihedral in a wing design?

  1. To provide lateral stability Correct answer.
  2. To increase engine cooling
  3. To reduce the stalling angle
  4. To increase climb performance

Explanation

Dihedral is the upward angle of the wings from the root, which gives lateral stability by producing a restoring roll when the aircraft sideslips. It does not directly improve climb or change the stalling angle, and it has no cooling function.

Question 9Aviation Fundamentals (Learning the Basics of Flight)

An aircraft is climbing at a constant airspeed. What is true of the forces along the flight path?

  1. Lift equals thrust
  2. Thrust equals weight
  3. Thrust balances drag plus a component of weight Correct answer.
  4. Drag is greater than thrust

Explanation

In a steady climb the thrust must overcome drag and also the rearward component of weight along the flight path. Lift is less than weight in a climb. If drag exceeded thrust the aircraft would decelerate.

Question 10Aviation Fundamentals (Learning the Basics of Flight)

What causes an aircraft to yaw to the left when power is applied at low airspeed in a propeller aircraft?

  1. The centre of gravity moving forward
  2. Torque reaction and slipstream effects on the propeller Correct answer.
  3. The ailerons moving to the up position
  4. The flaps being extended

Explanation

At high power and low airspeed, propeller torque reaction, spiralling slipstream and asymmetric blade effect combine to yaw the aircraft, often to the left. The pilot counters this with rudder. Ailerons, flaps and centre of gravity do not cause this power-related yaw.

Question 11Aviation Fundamentals (Learning the Basics of Flight)

What does the term 'best glide speed' mean for an aircraft?

  1. The speed giving the fastest possible descent
  2. The speed giving the greatest distance for each unit of height lost Correct answer.
  3. The speed at which the aircraft stalls
  4. The speed at which the engine produces most power

Explanation

Best glide speed is the airspeed that maximises the lift-to-drag ratio, giving the greatest horizontal distance per unit of altitude lost. It is used in engine-failure glide planning. It is not the fastest descent or the stall speed.

Question 12Aviation Fundamentals (Learning the Basics of Flight)

Which statement about the centre of gravity and stability is correct?

  1. A forward centre of gravity makes the aircraft uncontrollable
  2. Centre of gravity has no effect on stability
  3. A rearward centre of gravity always improves stability
  4. A forward centre of gravity generally improves longitudinal stability Correct answer.

Explanation

Moving the centre of gravity forward increases the nose-down moment and the restoring tendency, improving longitudinal stability but increasing elevator loads. A rearward centre of gravity reduces stability and can become dangerous. The centre of gravity therefore strongly affects stability.

Question 13Aviation Fundamentals (Learning the Basics of Flight)

What is the purpose of a wing's leading-edge slat?

  1. To reduce the wing area
  2. To delay airflow separation at high angles of attack Correct answer.
  3. To increase the aircraft's weight
  4. To act as a primary pitch control

Explanation

Slats extend from the leading edge to energise the airflow and delay separation, allowing a higher angle of attack before stall. They improve low-speed lift. They do not change weight, reduce wing area or control pitch.

Question 14Aviation Fundamentals (Learning the Basics of Flight)

What is the main advantage of a tricycle landing gear configuration over a tailwheel configuration on the ground?

  1. Lower stall speed
  2. Greater fuel capacity
  3. Higher cruise speed
  4. Better forward visibility and easier directional control Correct answer.

Explanation

A tricycle gear places the nose wheel forward, giving better forward visibility and making ground handling easier, especially in crosswinds. It does not directly improve cruise speed, fuel capacity or stall speed.

Question 15Aviation Fundamentals (Learning the Basics of Flight)

Which instrument uses the pitot-static system to indicate airspeed?

  1. The altimeter
  2. The heading indicator
  3. The vertical speed indicator
  4. The airspeed indicator Correct answer.

Explanation

The airspeed indicator compares pitot pressure with static pressure to show the speed of the aircraft through the air. The altimeter and vertical speed indicator use static pressure only. The heading indicator is a gyroscopic instrument and does not use pitot-static pressure.

Question 16Aviation Fundamentals (Learning the Basics of Flight)

What happens to the indicated airspeed as an aircraft climbs at a constant true airspeed?

  1. Indicated airspeed stays the same
  2. Indicated airspeed becomes zero
  3. Indicated airspeed decreases Correct answer.
  4. Indicated airspeed increases

Explanation

As altitude increases, air density falls, so the dynamic pressure measured by the pitot tube decreases. For a constant true airspeed the indicated airspeed therefore reads lower. True airspeed is higher than indicated airspeed at altitude.

Question 17Aviation Fundamentals (Learning the Basics of Flight)

What is the function of the elevator trim tab?

  1. To indicate the aircraft's altitude
  2. To control the aircraft's yaw
  3. To increase engine power
  4. To relieve control pressure needed to hold a pitch attitude Correct answer.

Explanation

The trim tab is a small surface on the elevator that adjusts the elevator's neutral position, reducing the stick force needed to maintain an attitude. It does not control yaw, increase power or indicate altitude.

Question 18Aviation Fundamentals (Learning the Basics of Flight)

Which of the following best describes a 'stall warning' device?

  1. A device that automatically lowers the landing gear
  2. A system that increases engine power near the ground
  3. A device that measures fuel quantity
  4. A system that alerts the pilot as the critical angle of attack approaches Correct answer.

Explanation

A stall warning system senses conditions such as airflow direction or angle of attack and warns the pilot before the critical angle is reached. It does not control landing gear, boost power or measure fuel.

Question 19Aviation Fundamentals (Learning the Basics of Flight)

What is the effect of extending flaps for landing?

  1. The aircraft's weight increases
  2. Drag decreases and lift decreases
  3. Lift and drag both increase, lowering the safe approach speed Correct answer.
  4. Only the stall speed increases

Explanation

Extending flaps increases camber and wing area, raising both lift and drag. This allows a slower, steeper approach with a lower stall speed. Flaps do not change the aircraft's weight and do not reduce lift.

Question 20Aviation Fundamentals (Learning the Basics of Flight)

What is the significance of the 'service ceiling' of an aircraft?

  1. The altitude at which the aircraft stalls
  2. The maximum altitude the aircraft can reach with no fuel
  3. The maximum altitude at which a specified climb rate can still be maintained Correct answer.
  4. The altitude at which the engine stops

Explanation

The service ceiling is the altitude at which the maximum rate of climb falls to a specified low value, so further climb becomes impractical. It is not an engine cut-off altitude or a stall altitude. It is defined with fuel remaining.

Question 21Aviation Fundamentals (Learning the Basics of Flight)

Which statement about the relationship between lift and airspeed is correct?

  1. Lift decreases as airspeed increases
  2. Lift is independent of airspeed
  3. Lift is proportional to the square of airspeed Correct answer.
  4. Lift is proportional to airspeed directly

Explanation

In the lift equation, lift is proportional to the square of airspeed. Doubling the airspeed therefore quadruples the lift for a given angle of attack. This is why less angle of attack is needed at higher speed.

Question 22Aviation Fundamentals (Learning the Basics of Flight)

What does the term 'adverse yaw' describe?

  1. The tendency to pitch up when power is applied
  2. Yaw caused by the rudder
  3. Yaw in the opposite direction to the intended turn when ailerons are applied Correct answer.
  4. The tendency to stall in a turn

Explanation

Adverse yaw occurs because the descending aileron produces more induced drag than the rising one, yawing the nose away from the intended turn. The pilot coordinates with rudder to counteract it. It is not caused by the rudder or by power changes.

Question 23Aviation Fundamentals (Learning the Basics of Flight)

What is the purpose of the rudder in normal flight?

  1. To increase lift
  2. To control pitch
  3. To control yaw and coordinate turns Correct answer.
  4. To control roll

Explanation

The rudder deflects airflow at the tail to produce yaw about the vertical axis, which is used mainly to coordinate turns and counter adverse yaw. Pitch is controlled by the elevator and roll by the ailerons. The rudder does not directly increase lift.

Question 24Aviation Fundamentals (Learning the Basics of Flight)

An aircraft is descending at a constant airspeed in a steady glide with the engine at idle. What is true of the forces?

  1. Thrust is greater than drag
  2. The forward component of weight balances drag Correct answer.
  3. Drag is zero
  4. Lift equals weight

Explanation

In a steady glide the thrust is negligible, so the component of weight acting along the flight path balances drag. Lift balances the remaining perpendicular component of weight and is less than the total weight. Drag is not zero.

Question 25Aviation Fundamentals (Learning the Basics of Flight)

Which of these best explains why an aircraft has a maximum takeoff weight limit?

  1. Performance and structural limits are defined for that weight Correct answer.
  2. The fuel tanks overflow above that weight
  3. The wings cannot generate any lift above that weight
  4. The engine cannot run above that weight

Explanation

Maximum takeoff weight is set so that takeoff, climb, landing and structural performance remain within certified limits. Exceeding it degrades climb and increases stall speed and structural loads. It is not a limit on lift generation, engine operation or fuel capacity.

Question 26Aviation Fundamentals (Learning the Basics of Flight)

Which four forces act on an aircraft in flight?

  1. Thrust, weight, inertia and momentum
  2. Lift, thrust, gravity and compression
  3. Lift, mass, power and friction
  4. Lift, weight, thrust and drag Correct answer.

Explanation

In steady flight four forces act: lift acts upward, weight acts downward through the centre of gravity, thrust acts forward along the flight path, and drag opposes motion. In unaccelerated flight lift balances weight and thrust balances drag.

Question 27Aviation Fundamentals (Learning the Basics of Flight)

What is the angle of attack?

  1. The angle between the wing chord line and the relative airflow Correct answer.
  2. The angle between the wing and the longitudinal axis
  3. The angle between the flight path and the vertical plane
  4. The angle between the fuselage centreline and the horizon

Explanation

Angle of attack is measured between the chord line of the wing and the direction of the relative airflow. It is a key control of lift and is distinct from pitch attitude, which is measured relative to the horizon.

Question 28Aviation Fundamentals (Learning the Basics of Flight)

What is the primary purpose of the horizontal stabiliser?

  1. To control roll about the longitudinal axis
  2. To increase drag for steeper descents
  3. To provide longitudinal stability and support the elevator Correct answer.
  4. To generate most of the aircraft's lift

Explanation

The horizontal stabiliser, or tailplane, is mounted aft of the centre of gravity and provides a restoring moment in pitch, giving longitudinal stability. It also carries the elevator used to change pitch.

Question 29Aviation Fundamentals (Learning the Basics of Flight)

Which statement correctly describes the relationship between angle of attack and lift at a fixed airspeed below the stall?

  1. Lift decreases steadily as angle of attack increases
  2. Lift increases as angle of attack increases up to the critical angle Correct answer.
  3. Lift increases only after the critical angle is exceeded
  4. Lift is unaffected by changes in angle of attack

Explanation

For a given airspeed, the lift coefficient rises roughly linearly with angle of attack until the critical angle is reached. Beyond that angle the airflow separates and lift falls sharply in the stall.

Question 30Aviation Fundamentals (Learning the Basics of Flight)

What is the purpose of the vertical stabiliser and fin?

  1. To provide directional stability in yaw Correct answer.
  2. To control pitch about the lateral axis
  3. To balance the aircraft in roll
  4. To generate lift at low airspeeds

Explanation

The vertical stabiliser provides a sideways aerodynamic surface aft of the centre of gravity, giving a restoring moment that keeps the aircraft aligned with the relative airflow. It also supports the rudder.

Question 31Aviation Fundamentals (Learning the Basics of Flight)

What does the term 'aspect ratio' describe for a wing?

  1. The ratio of wing thickness to chord length
  2. The angle at which the wing is set to the fuselage
  3. The ratio of wingspan squared to wing area Correct answer.
  4. The ratio of wing area to aircraft weight

Explanation

Aspect ratio is the square of the wingspan divided by the wing area. High aspect ratio wings are long and narrow and generally produce less induced drag for a given lift.

Question 32Aviation Fundamentals (Learning the Basics of Flight)

What is the function of the altimeter in an aircraft?

  1. To display the aircraft's height above a selected pressure datum Correct answer.
  2. To show the aircraft's speed through the air
  3. To display the aircraft's heading
  4. To indicate the rate of climb or descent

Explanation

The altimeter is a pressure instrument that senses static pressure and displays height above the pressure level set in the subscale. Setting the correct reference, such as QNH or standard pressure, is essential for accurate readings.

Question 33Aviation Fundamentals (Learning the Basics of Flight)

Which statement about the centre of pressure of a wing is correct?

  1. It is always located at the wing's leading edge
  2. It is the point where the resultant aerodynamic force acts Correct answer.
  3. It is fixed at the wing's trailing edge
  4. It coincides with the centre of gravity in all flight conditions

Explanation

The centre of pressure is the point through which the total aerodynamic force on the wing can be considered to act. Its position moves as angle of attack changes, which affects pitching moments.

Question 34Aviation Fundamentals (Learning the Basics of Flight)

An aircraft of mass 1200 kg is in steady level flight. Taking g as 10 m/s squared, what lift is required in newtons?

  1. 120 000 N
  2. 1 200 N
  3. 12 000 N Correct answer.
  4. 120 N

Explanation

In steady level flight lift equals weight. Weight is mass times gravitational acceleration, so 1200 kg times 10 m/s squared equals 12 000 N.

Question 35Aviation Fundamentals (Learning the Basics of Flight)

How does induced drag change as an aircraft's airspeed increases at a constant weight and altitude?

  1. It remains constant regardless of airspeed
  2. It increases until the stall speed is reached
  3. It increases because dynamic pressure rises
  4. It decreases because less lift coefficient is needed Correct answer.

Explanation

Induced drag is associated with the generation of lift and is greatest at low speed and high angle of attack. As airspeed rises, the required lift coefficient falls, so induced drag decreases.

Question 36Aviation Fundamentals (Learning the Basics of Flight)

What is the relationship between total drag and airspeed in level flight?

  1. Total drag reaches a minimum at the speed where induced and parasite drag are equal Correct answer.
  2. Total drag is lowest at the stall speed
  3. Total drag rises continuously as airspeed increases
  4. Total drag falls continuously as airspeed increases

Explanation

Parasite drag increases with the square of airspeed while induced drag decreases as airspeed rises. The sum of the two is lowest at the speed where they are equal, which corresponds to the best lift-to-drag ratio.

Question 37Aviation Fundamentals (Learning the Basics of Flight)

What is meant by the load factor of an aircraft?

  1. The total weight carried divided by the wing area
  2. The ratio of thrust to drag in level flight
  3. The ratio of total lift to the aircraft's weight Correct answer.
  4. The ratio of airspeed to stall speed

Explanation

Load factor expresses how many times the lift being produced compares with the aircraft's weight. In a level turn it increases with bank angle and raises the structural and aerodynamic demands on the aircraft.

Question 38Aviation Fundamentals (Learning the Basics of Flight)

In a steady level turn at 60 degrees of bank, approximately what load factor is experienced?

  1. 1.4
  2. 2.0 Correct answer.
  3. 3.0
  4. 1.0

Explanation

Load factor in a level turn equals one divided by the cosine of the bank angle. The cosine of 60 degrees is 0.5, so the load factor is 2.0.

Question 39Aviation Fundamentals (Learning the Basics of Flight)

Why does an aircraft's stall speed increase when it is banked?

  1. The engine produces less thrust in a turn
  2. The increased load factor requires more lift at the same airspeed Correct answer.
  3. The wing's critical angle of attack reduces with bank
  4. The wing area effectively decreases in a turn

Explanation

In a banked turn the lift vector tilts and its vertical component must still equal weight, so total lift and load factor rise. To produce that extra lift at the same angle of attack, a higher airspeed is required, raising the stall speed.

Question 40Aviation Fundamentals (Learning the Basics of Flight)

What happens to the stall speed if an aircraft's weight is increased?

  1. It decreases in proportion to the weight
  2. It increases in proportion to the square root of the weight Correct answer.
  3. It stays the same because the wing is unchanged
  4. It halves when weight is doubled

Explanation

Stall speed depends on the square root of the load supported by the wing. If weight increases, more lift is needed at the critical angle of attack, so the stall speed rises as the square root of the weight ratio.

Question 41Aviation Fundamentals (Learning the Basics of Flight)

What is the effect of ground effect on an aircraft shortly after takeoff?

  1. The stall speed rises significantly in ground effect
  2. Parasite drag increases sharply near the ground
  3. Induced drag is reduced and lift is increased for a given angle of attack Correct answer.
  4. The aircraft tends to pitch nose-down abruptly

Explanation

Close to the ground the wingtip vortices are suppressed and the downwash is reduced, which lowers induced drag and increases lift at a given angle of attack. This can let the aircraft leave the ground at a lower speed than it can sustain out of ground effect.

Question 42Aviation Fundamentals (Learning the Basics of Flight)

Which statement about the four-stroke cycle of a piston engine is correct?

  1. The power stroke follows the compression stroke Correct answer.
  2. The exhaust stroke follows the intake stroke directly
  3. The intake stroke follows the power stroke
  4. The compression stroke follows the exhaust stroke

Explanation

The sequence is intake, compression, power and exhaust. The mixture is compressed before ignition, and the expanding gases during the power stroke drive the piston.

Question 43Aviation Fundamentals (Learning the Basics of Flight)

What is the purpose of a magneto in an aircraft piston engine?

  1. To charge the aircraft's battery during flight
  2. To drive the propeller through a reduction gear
  3. To control the fuel-air mixture entering the cylinders
  4. To provide a self-contained ignition spark independent of the battery Correct answer.

Explanation

Magnetos generate high-voltage pulses for the spark plugs using rotating magnets and coils, so ignition does not depend on the aircraft's electrical system. This independence is why engines are typically fitted with two magnetos for redundancy.

Question 44Aviation Fundamentals (Learning the Basics of Flight)

What is the function of the carburettor in a piston engine?

  1. To increase the pressure of fuel before injection
  2. To mix fuel with air in the correct proportion for combustion Correct answer.
  3. To cool the engine oil during operation
  4. To regulate the propeller pitch

Explanation

The carburettor meters fuel into the incoming air stream to produce a combustible mixture. The mixture ratio is adjusted by the mixture control as altitude changes.

Question 45Aviation Fundamentals (Learning the Basics of Flight)

What causes carburettor icing in an aircraft engine?

  1. Fuel contamination with water in the tanks
  2. Excessive oil temperature in the engine sump
  3. Overheating of the spark plugs during descent
  4. A drop in temperature and pressure as air and fuel pass through the venturi Correct answer.

Explanation

As air accelerates through the carburettor venturi its pressure and temperature fall, and fuel vaporisation further cools the mixture. Moisture in the air can then freeze on the internal surfaces, restricting the airflow.

Question 46Aviation Fundamentals (Learning the Basics of Flight)

An aircraft has a true airspeed of 120 knots and a headwind of 30 knots. What is the approximate ground speed?

  1. 30 knots
  2. 90 knots Correct answer.
  3. 150 knots
  4. 120 knots

Explanation

Ground speed is true airspeed adjusted for the wind component along the flight path. A headwind reduces progress over the ground, so 120 minus 30 gives 90 knots.

Question 47Aviation Fundamentals (Learning the Basics of Flight)

Why does an aircraft's true airspeed increase with altitude for a given indicated airspeed?

  1. Gravity decreases with altitude, reducing the aircraft's weight
  2. The engine produces more thrust at higher altitude
  3. Air density decreases, so the same dynamic pressure occurs at a higher true speed Correct answer.
  4. The pitot tube becomes more sensitive at low pressure

Explanation

The airspeed indicator responds to dynamic pressure, which depends on density and the square of true speed. As density falls with altitude, the same dynamic pressure corresponds to a higher true airspeed, so true airspeed exceeds indicated airspeed at height.

Question 48Aviation Fundamentals (Learning the Basics of Flight)

What is the significance of the manoeuvring speed, VA, of an aircraft?

  1. It is the speed at which the aircraft has the best climb rate
  2. It is the maximum speed for flight in smooth air only
  3. Below it, full control deflection will stall the wing before overstressing the structure Correct answer.
  4. Above it, the aircraft can be manoeuvred without any risk of stall

Explanation

Manoeuvring speed is the maximum speed at which abrupt full deflection of a single control surface will stall the wing before the limit load factor is exceeded. Above VA, gusts or full control inputs can overstress the airframe.

Question 49Aviation Fundamentals (Learning the Basics of Flight)

Why is a rearward centre of gravity position significant for longitudinal stability?

  1. It has no effect on stability as long as the aircraft is within limits
  2. It increases the aircraft's stall speed at all angles of attack
  3. It increases the nose-down moment making the aircraft harder to rotate
  4. It reduces the restoring pitch moment and can make the aircraft less stable Correct answer.

Explanation

Moving the centre of gravity rearward reduces the distance to the horizontal stabiliser and lowers its restoring moment. Stability in pitch decreases, control forces may lighten and recovery from a stall or upset can become more difficult.

Question 50Aviation Fundamentals (Learning the Basics of Flight)

How does a constant-speed propeller differ from a fixed-pitch propeller?

  1. It cannot be used with a reduction gear
  2. Its blades are fixed at the most efficient angle for cruise
  3. Its blade angle is varied to maintain a selected engine speed Correct answer.
  4. It always turns at a speed directly proportional to airspeed

Explanation

A constant-speed propeller uses a governor to change blade angle so the engine maintains the selected RPM as airspeed and power change. This allows efficient operation across a wider range of conditions than a fixed-pitch propeller.