Propellers Flashcards
What does the pilot do to change the RPM of an engine equipped with a constant speed propeller when it is operating within the constant speed range? (AM.III.M.K4)
The pilot moves the propeller pitch control.
This changes the compression on the speeder spring inside the governor which moves the pilot valve. The pilot valve directs oil into or out of the propeller to change the pitch of the blades. The change in pitch, changes the air load on the propeller which changes the RPM.
What is the difference between a controllable propeller and a constant speed propeller? (AM.III.M.K4)
Basically it is the control system.
A controllable-pitch propeller uses a manually operated oil valve to control the pitch.
A constant-speed propeller uses a governor to control the valve.
When making a magneto check on an engine equipped with a constant speed propeller, should the propeller control be in the low pitch or the high pitch position?
It should be in the low pitch, high RPM position.
Where do you find a list of the lubricants that are approved for use in a constant-speed propeller? (AM.III.M.K6)
In the maintenance manual for the propeller
What is the extent of the repairs a mechanic with a Powerplant rating can make to a propeller? (AM.III.M.K6)
Only minor repairs or minor alterations.
Where can examples of acceptable repairs to aluminum alloy propeller blades be found? (AM.III.M.K6)
In AC 43.13-1B, Chapter 8, Section 4,
&
in the propeller manufacturer’s service manual.
Is it permissible to cold straighten a damaged aluminum alloy propeller blade to facilitate shipping it to a repair station? (AM.III.M.K6)
No, this could cause hidden damage that might make the blade impossible to repair.
What would be the classification of maintenance for shortening a propeller blade? (AM.III.M.K6)
Major repairs.
May transverse cracks in a metal propeller blade be repaired? (AM.III.M.K6)
No, a transverse crack of any size is reason for rejecting the blade.
What damage to an aluminum alloy propeller blade can be repaired by a mechanic holding a Powerplant rating? (AM.III.M.K6)
Small roughness, nicks, and scratches in the leading edge of the blades.
How are small nicks removed from the leading edge of a propeller blade? (AM.III.M.K6)
File them out with fine file or stone, leaving a smooth contour.
How can you determine that a surface scratch in an aluminum alloy propeller blade is not actually a crack? (AM.III.M.K6)
-Clean the damage out
-Use dye-penetrant liquid
-Allow it time to seep into a crack if one is present, then wipe all of the liquid off the surface.
-Spray the area with a developer. If the damage is actually a crack, the developer will pull the penetrant out and it will form a visible line.
Who, or what facility, is authorized to perform major repairs to a propeller? (AM.III.M.K6)
An FAA-approved propeller repair station that is authorized for the specific propeller.
What checks and maintenance is a mechanic with a Powerplant rating allowed to make on a propeller? (AM.III.M.K6)
- Check the track of the propeller blades.
- Remove small scratches from the blades.
- Check the balance of a propeller.
- Lubricate the propeller.
What adjustment can a mechanic with a Powerplant rating make to a propeller governor? (AM.III.M.K6)
Adjust the Maximum RPM Stop.
