AT 208 Final Exam Part 3 - Wood
Structures & Fabric Covering and Repair
Exam Questions and Answers Graded A+
Softwood characteristics
Main species - Correct answer-High strength-to-weight ratio
Sitka Spruce
Hardwood characteristics
Where used? - Correct answer-Heavier than softwoods but stronger. Used where its
strength advantages makes the extra weight acceptable.
Mahogany, Birch, White Ash
Plywood
Advantages over solid wood?
How is grain alligned? - Correct answer-Advantages:
not likely to warp
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,resistant to cracking
change in dimension negligible with change in moisture content
Each layer has grain running at large angle to previous layer
Aircraft plywood is much higher quality than commercial.
Laminated Wood
What is it?
How is grain alligned?
Advantages over solid wood?
Uses? - Correct answer-Several layers of solid wood bonded together with
adhesive.
Each layer has grain running in same direction.
More rigid, more resistant to warpage than solid wood.
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, Used for curved components: wing-tip bows, fuselage formers
Casein
What is it?
Is it still used? - Correct answer-Oldest of the wood glues, made from milk.
Deteriorates over time if exposed to moisture or temp changes. No longer used
Plastic Resin
What is it? - Correct answer-Powdered glue mixed with water to form paste, must
be aircraft type
Resorcinol
What is it?
Color? - Correct answer-FAA recommended two-part resin and hardener, water
resistant, easy to identify by dark burgundy color
Epoxy
____ is experimental aircraft standard, but not FAA approved.
What is it less critical of? - Correct answer-T88
Less critical of joint quality and clamping pressure
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
Structures & Fabric Covering and Repair
Exam Questions and Answers Graded A+
Softwood characteristics
Main species - Correct answer-High strength-to-weight ratio
Sitka Spruce
Hardwood characteristics
Where used? - Correct answer-Heavier than softwoods but stronger. Used where its
strength advantages makes the extra weight acceptable.
Mahogany, Birch, White Ash
Plywood
Advantages over solid wood?
How is grain alligned? - Correct answer-Advantages:
not likely to warp
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
,resistant to cracking
change in dimension negligible with change in moisture content
Each layer has grain running at large angle to previous layer
Aircraft plywood is much higher quality than commercial.
Laminated Wood
What is it?
How is grain alligned?
Advantages over solid wood?
Uses? - Correct answer-Several layers of solid wood bonded together with
adhesive.
Each layer has grain running in same direction.
More rigid, more resistant to warpage than solid wood.
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
, Used for curved components: wing-tip bows, fuselage formers
Casein
What is it?
Is it still used? - Correct answer-Oldest of the wood glues, made from milk.
Deteriorates over time if exposed to moisture or temp changes. No longer used
Plastic Resin
What is it? - Correct answer-Powdered glue mixed with water to form paste, must
be aircraft type
Resorcinol
What is it?
Color? - Correct answer-FAA recommended two-part resin and hardener, water
resistant, easy to identify by dark burgundy color
Epoxy
____ is experimental aircraft standard, but not FAA approved.
What is it less critical of? - Correct answer-T88
Less critical of joint quality and clamping pressure
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
