17.7 - Propeller Storage And Preservation

Question 1

Wha manual do uninstalled props use

Answer 1

Use PMM instead of AMM

Question 2

3 months - short term
Installed props.

Answer 2

Wooden fixed pitch props need to be horizontal.
Mild soap and water for cleaning.
Store between 10-20 degrees C.
Wood props should not be wrapped in way that will seal them from air. To prevent rot.
Metal fixed pitch props is similar but with corrosion inspections.
Variable pitch mechanisms need to be exercised prior to shut down.

Question 3

What is important to note about lanolin and de-icing boots

Answer 3

Do not let lanolin contact de-icing boots.

Question 4

What should storage conditions be for wooden props

Answer 4

Clean, dark, dry, well ventilated.

Question 5

Short term (3months) storage of uninstalled props and prop assemblies.

Answer 5

Wooden props stored horizontally to maintain even moisture distribution.
Wooden Props with automatic pitch control, hub must be filled with oil and turned every 2 weeks, with inspections for deterioration.
Metal props stored vertically with the hub supported by a mandrel.
Coated with lanolin or corrosion inhibitor for metal props stored vertically wa

Question 6

What must happen to the pitch change mechanism in short term preservation of uninstalled props

Answer 6

Drained of oil and flushed with corrosion inhibitor, wrapped in wax paper.

Question 7

What must the storage crate be labelled with

Answer 7

Prop type and serial number.
Component part numbers.
Modification standard.
Original date of preservation
Date of blade bearing exercise and inspections if applicable.

Question 8

What documentation do all parts held in storage require

Answer 8

Form 1
Certificate of conformity
Certificate of release to service.

Question 9

6 month storage requirements

Answer 9

Pre loaded bearings must be rotated to stop brinelling at the 6 month mark

Question 10

12 month storage requirements

Answer 10

Bearings for preloaded blades exercised at 6, 9, and 12 months.
At 12 month mark, visually inspect bearings for brinelling and corrosion. Bearings lubricated.
Blades re-inhibited.

Question 11

Storage for 3 years or over 12 months.

Answer 11

At 3 year mark, prop needs to be sent for an overhaul.
If it is dismantled and remains in its original packaging, it does not require re-inhibiting every year, but bearings may still need exercising and inspecting.