Fabrics Flashcards
- What is the main reason Sitka spruce is used in aircraft structures?• a) Low cost
• b) Strength and shock resistance
• c) High-density material
• d) Easy to glue
- b) Strength and shock resistance
- Which of the following is not a requirement for Sitka spruce to meet aircraft grade specifications?• a) Kiln-dried under approved conditions
• b) Minimum specific gravity of 0.36
• c) Maximum slope of grain of 1:10
• d) No fewer than six annular rings per inch
c) Maximum slope of grain of 1:10
What does solid wood refer to in aircraft construction?
• a) An assembled product of wood and glue • b) Beams or spars made from a single piece of wood • c) Layers glued together with grain running parallel • d) High-density commercial products like compreg
. b) Beams or spars made from a single piece of wood
- Which wood type can be used as a substitute for Sitka spruce despite difficulties with gluing?• a) Noble Fir
• b) Douglas Fir
• c) Yellow Poplar
• d) Port Orford White Cedar
d) Port Orford White Cedar
What is the maximum permissible slope of grain for wood used in aircraft structures?
• a) 1:10 • b) 1:15 • c) 1:20 • d) 1:25
B) 1:15
Which wood type has slightly less strength than Sitka spruce and low shock resistance?
• a) Douglas Fir • b) Noble Fir • c) Yellow Poplar • d) Western Hemlock
C) yellow poplar
Why is aviation wood usually quarter-sawn?
• a) To reduce warping • b) To increase strength • c) To reduce shrinkage • d) To improve workability
c) To reduce shrinkage
How is the number of growth rings per inch determined for wood assessment?
• a) Measuring the width of each ring • b) Counting rings on the wide face of the board • c) Counting rings at the end of the board • d) Measuring the distance between the rings
c) Counting rings at the end of the board
Which of the following is NOT a factor that contributes to the rate of fabric deterioration on an aircraft?
a) Type of operation
b) Exposure to wind
c) Climate and humidity
d) Storage conditions
Answer: b) Exposure to wind
How often should the fabric covering of an aircraft be checked?
a) Once every 15 years
b) Monthly
c) As per the approved maintenance schedule and before Airworthiness Certificate renewal
d) Only when defects are noticed
Answer: c) As per the approved maintenance schedule and before Airworthiness Certificate renewal
What happens to an aircraft structure if it is stored outside?
a) It becomes stronger due to sun exposure
b) Ultraviolet radiation and sun exposure can damage the structure
c) The fabric becomes waterproof
d) The structure cools down more rapidly
Answer: b) Ultraviolet radiation and sun exposure can damage the structure
Which of the following is NOT a defect that should be inspected in the fabric covering?
a) Loose finishing tape
b) Fabric tears
c) Excessively taut fabric
d) Stone damage
Answer: c) Excessively taut fabric
What are the consequences of excessive fabric tension?
a) Improved aerodynamics
b) Warping of longerons, wing ribs, and trailing edges
c) Reduced drag
d) Decreased fuel efficiency
Answer: b) Warping of longerons, wing ribs, and trailing edges
What causes temporary wrinkles in a fabric coated with dope?
a) High-quality dope film
b) Rapid cooling in the shade
c) Moisture absorption, thick dope coating, and rapid temperature changes
d) Application of varnish
Answer: c) Moisture absorption, thick dope coating, and rapid temperature changes
Which fabric is unaffected by UV radiation but deteriorates with acid rain and chafing?
a) Natural fibers
b) Polyester filaments
c) Glass fabric
d) Synthetic fibers
Answer: c) Glass fabric
How should cracks in the dope coating be repaired?
a) Leave them as they are
b) Seal them or remove and replace coatings in the affected area
c) Apply water
d) Heat the area
Answer: b) Seal them or remove and replace coatings in the affected area
Why is protecting the structure beneath the fabric covering important?
a) To add extra weight
b) To prevent wood rot and allow inspections
c) To make the aircraft look newer
d) To increase speed
Answer: b) To prevent wood rot and allow inspections
Why should wooden aircraft structures be kept in well-ventilated hangars?
a) To allow air to circulate around the engine
b) To prevent moisture condensation that leads to wood deterioration
c) To protect from bird droppings
d) To allow easier access for maintenance
b) To prevent moisture condensation that leads to wood deterioration
What is the purpose of wiping wooden aircraft structures with a damp cloth and applying furniture polish?
a) To disinfect the wood
b) To remove paint residue
c) To keep the wood clean and polished
d) To prepare the wood for repair
c) To keep the wood clean and polished
Which of the following is NOT a required property of wood preservatives for aircraft structures?
a) They must be non-toxic to fungi, pests, and marine organisms
b) They must possess satisfactory permanence
c) They must be free from objectionable properties
d) They should not have corrosive properties
a) They must be non-toxic to fungi, pests, and marine organisms
What is the main purpose of applying chemical preservatives to wooden aircraft structures?
a) To change the color of the wood
b) To protect the wood from fungi, insects, and marine borers
c) To make the wood heavier for stability
d) To prevent cracking from temperature changes
b) To protect the wood from fungi, insects, and marine borers
What is the primary objective of interior finishes on wooden aircraft structures?
a) To make the interior look aesthetically pleasing
b) To protect the wood against moisture content changes
c) To prevent cracking from sunlight exposure
d) To ensure the wood does not conduct electricity
b) To protect the wood against moisture content changes
Why should end grain surfaces of wooden aircraft members be sealed thoroughly?
a) They are less absorbent and can be left unsealed
b) They are more absorbent and vulnerable to moisture entry
c) They can crack easily when exposed to sunlight
d) They are already protected by the wood’s natural oils
b) They are more absorbent and vulnerable to moisture entry
How should bolt holes in wooden aircraft structures be sealed?
a) With oil to prevent drying
b) With varnish or acceptable sealer and allowed to cure before installation
c) With glue to hold the bolts in place
d) With paint to match the aircraft’s color
b) With varnish or acceptable sealer and allowed to cure before installation
