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Flashcards in New ppt Props Deck (37)
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1
Q

Allows propeller to produce thrust in reverse direction to produce deceleration (braking). Negative blade angles. (the greater the RPM the greater the reverse thrust)

A

Reverse pitch

2
Q

what changes the blade angle pitch on a constant-speed prop?

A

prop governor

3
Q

how is the propeller mounted in a low power or piston engine aircraft?

A

crankshaft

4
Q

an older type of Adjustable-pitch propeller that can only be adjusted on the ground with the engine off.

A

Ground-Adjustable Propellers

5
Q

the flat part of the blade that faces the pilot

A

Blade face

6
Q

transition point to reverse

A

Disking- Neutral/Zero pitch

7
Q

contains propeller information and is where it attaches to the engine

A

Blade hub

8
Q

the frequency at which the system will vibrate if it is excited by a single pulse

A

Resonant Frequency

9
Q

A ______ propeller is mounted to the aft end of an engine and push the airplane through the air

A

Pusher

10
Q

The propeller is able to convert about __% of the brake horsepower to thrust horsepower

A

85%

11
Q

The actual distance the propeller travels in one revolution through the air (friction drag & weight)

A

Effective Pitch

12
Q

A small “Bite” of air ( T/O, climb)

A

Fine pitch (High RPM)

13
Q

will automatically maintain a constant RPM for changes in flight conditions (tailwind, headwind, air pressure/temperature changes.

A

Constant-Speed Propellers

14
Q

When a propeller is connected to an engine and produces thrust, aerodynamic and mechanical forces causes the propeller to?

A

Vibrate

15
Q

may have their pitch adjusted in flight, but each setting must be made manually by pilot.

A

Controllable-Pitch Propellers

16
Q

are designed to optimize a particular RPM and forward motion

A

Fixed-Pitch Propellers

17
Q

What is the purpose of the propeller ?

A

To convert engine brake horsepower to thrust horsepower

18
Q

caused by a low pressure area forward of the blade axis in rotation and Rotates the blades to a higher blade angle, decreasing RPM (COARSE PITCH)

A
19
Q

Stalling degrees on prop blade?

A

If exceeded to 15 degrees

20
Q

The difference between the Geometric and Effective Pitches. The less the losses the more efficient the propeller.

A

Prop Slip

21
Q

Caused by the resistance of the air to propeller rotation. Bends blades in opposite direction of rotation

A
22
Q

Blades trying to remain in parallel rotation to the propeller plane of rotation and Rotates the blades to a lower angle (toward 0, which increases RPM) (FINE PITCH)

A
23
Q

Some propeller engine combinations have a critical operating range where vibrations forces are too great to stay in. _______ wil indicate this range.

A

Tachometer

24
Q

A ______ propeller is mounted to the front of the engine and pulls the airplane through the air

A

Tractor

25
Q

Why is the blade twisted ?

A

So it can Compensate for difference in rotational speed of the propeller blade and allows for more even distribution of thrust

26
Q

Selection that allows blades to be moved to pitch angle of almost +90 degrees in event of engine shut-down (reduces drag). RPM = 0 (failed engine)

A

Feather

27
Q

Allows a big “Bite” of air for cruise.

A

Coarse pitch (Low RPM)

28
Q

how is the propeller mounted in a high power or turboprop engine aircraft?

A

gear reduction system

29
Q

Caused by propeller weight tending to throw the blades away from the centre of rotation (hub). This is the strongest force acting on the propeller

A
30
Q

What safety precautions should you take before working on or rotating a propeller ?

A

Mixture to Cut off

Magneto switch to Off

Fuel selector valve to off

Ground the p- leads

Remove the spark plug leads

31
Q

Most effective angle of attack for a prop blade?

A

2 & 4 degrees

32
Q

A fixed-pitch propeller to optimize takeoff and climb but slower and less efficient cruise (Example blade angle of attack 2 degrees)

A

Climb Propeller

33
Q

the distance the propeller should travel in one revolution through a solid (no losses).

A

Geometric Pitch

34
Q

the cambered side of the blade similar to a wings upper surface

A

blade back

35
Q

Caused by thrust loads. Compression and tension acting upon the blades and Bends the blades forward in the line of flight

A
36
Q

A fixed-pitch propeller with a high blade angle to optimize cruise and high altitude flight. Longer takeoff and slower, less efficient climb (Example blade angle of attack 4 degrees).

A

Cruise Propeller

37
Q

A compromise between a Climb and Cruise propeller (Example blade angle of attack 3 degrees).

A

Standard Propeller