6.3.2 Wooden Structures Flashcards
What type of structure do fabric covered aircraft have
Truss type
What may the wing spars be made from
Sika spruce and may be solid or laminated
What is the advantage of a laminated spar over a solid spar
A laminated spar is just as strong and is much cheaper
What are the wing spars on wooden aircraft separated by
Compression members made of aluminium tubing or steel
What type of loads does a built up box spar take
Torsional and bending
What conditions should an aircraft be in for inspection purposes
In a dry well ventilated hangar with all inspection panels removed
What must be done before inspecting glued joints
The aircraft must be fully dried
What is the main problem associated with inspecting glued joints
There is no good non destructive testing
Access is difficult
What shape should access holes be
Access holes should be circular in shape and special tools used to avoid jagged edges
What must be done to the edges of all access holes
They must be smoothed with fine glass paper before inspection
What must be done before checking a glue line
All protective coatings must be removed by careful scraping
How is the inspection of a glue line carried out
With a magnifying glass and feeler gauge
What must be done if penetration is had on a glue line when inspecting
The piece must be rejected
How is dry rot identified
By small patches of crumbling wood
How would water penetration be identified in wood
Dark discolouration and grey streaks
What should be done to drain holes during routine maintenance
They should be cleaned out
How is a timber shrinkage inspection carried out
By removing paint or varnish and inserting a feeler gauge
What is had when elongated bolt holes are found
Can be due to landing or shear stresses
When would bruising or crushing be found
Where someone has over tightened a bolt
What type of loads are glued joints mainly designed to take
Shear loads
What is done to timber after it has been cut
It is stacked ready for shipment for 60 days
How is timber seasoned
In drying sheds for 1-3 years