17.2 Construction

Question 1

Where are the requirements for the design, manufacture and testing of propellers is specified?

Answer 1

Annex IX to ED Decision 2020/006/R,

Question 2

What are wood props used on?

Answer 2

often used on older fixed pitch propellers and some controllable pitch propellers fitted on vintage

Question 3

What is the most common wood?

Answer 3

Birch

Question 4

How many layers of wood are used and what is it they form?

Answer 4

5, a blank

Question 5

What happens to the blank?

Answer 5

Roughly shaped and laid to rest for a week

Question 6

After the rest period what is the blank known as?

Answer 6

A white

Question 7

When are the centre holes and bolt holes drilled?

Answer 7

After the white has been shaped

Question 8

How is the blade tipping secured?

Answer 8

Countersunk screws
Copper rivets at the tip

Question 9

Why are small holes (1.016mm) drilled into the tip?

Answer 9

To allow moisture to escape

Question 10

What is the main difference between variable pitch to fixed pitch wooden props?

Answer 10

Variable have the blade shank secured into a metal sleeve using lag screws.

Question 11

What is a lag screw?

Answer 11

coach bolt - a heavy duty wood screw with a square or hexagonal head