New ppt Props

Question 1

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

Answer 1

Reverse pitch

Question 2

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

Answer 2

prop governor

Question 3

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

Answer 3

crankshaft

Question 4

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

Answer 4

Ground-Adjustable Propellers

Question 5

the flat part of the blade that faces the pilot

Answer 5

Blade face

Question 6

transition point to reverse

Answer 6

Disking- Neutral/Zero pitch

Question 7

contains propeller information and is where it attaches to the engine

Answer 7

Blade hub

Question 8

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

Answer 8

Resonant Frequency

Question 9

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

Answer 9

Pusher

Question 10

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

Answer 10

85%

Question 11

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

Answer 11

Effective Pitch

Question 12

A small “Bite” of air ( T/O, climb)

Answer 12

Fine pitch (High RPM)

Question 13

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

Answer 13

Constant-Speed Propellers

Question 14

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

Answer 14

Vibrate

Question 15

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

Answer 15

Controllable-Pitch Propellers

Question 16

are designed to optimize a particular RPM and forward motion

Answer 16

Fixed-Pitch Propellers

Question 17

What is the purpose of the propeller ?

Answer 17

To convert engine brake horsepower to thrust horsepower

Question 18

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)

Answer 18

Question 19

Stalling degrees on prop blade?

Answer 19

If exceeded to 15 degrees

Question 20

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

Answer 20

Prop Slip

Question 21

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

Answer 21

Question 22

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)

Answer 22

Question 23

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

Answer 23

Tachometer

Question 24

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

Answer 24

Tractor

Question 25

Why is the blade twisted ?

Answer 25

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

Question 26

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)

Answer 26

Feather

Question 27

Allows a big “Bite” of air for cruise.

Answer 27

Coarse pitch (Low RPM)

Question 28

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

Answer 28

gear reduction system

Question 29

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

Answer 29

Question 30

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

Answer 30

Mixture to Cut off Magneto switch to Off Fuel selector valve to off Ground the p- leads Remove the spark plug leads

Question 31

Most effective angle of attack for a prop blade?

Answer 31

2 & 4 degrees

Question 32

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

Answer 32

Climb Propeller

Question 33

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

Answer 33

Geometric Pitch

Question 34

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

Answer 34

blade back

Question 35

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

Answer 35

Question 36

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).

Answer 36

Cruise Propeller

Question 37

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

Answer 37

Standard Propeller