WorksheetsWooden Wing Construction Quiz
Total questions: 46
Worksheet time: 23mins
The main lengthwise members in a wooden wing are called:
Ribs
Spars
Stringers
In a truss-type wooden wing, the members that separate the spars are:
Drag wires
Compression members
Stringers
Sitka spruce spars on light aircraft are commonly:
Solid only
Laminated only
Solid or laminated
Steel or heavy-wall aluminium tubes between spars primarily act as:
Tension ties
Compression members
Torsion boxes
Drag wires run:
Rear spar inboard → front spar outboard
Front spar inboard → rear spar outboard
Between ribs only
Anti-drag wires run:
Rear spar inboard → front spar outboard
Front spar outboard → rear spar inboard
Tip rib → root rib
A box spar added between spars primarily increases:
Fuel capacity
Bending and torsional stiffness
Ease of inspection
Typical wooden box spars use long upper/lower belts (“booms”) linked by:
Steel webs
Plywood webs
Fabric webs
Before detailed inspection, aircraft should be:
Stored outside to ventilate glue fumes
Housed dry and well-ventilated with panels removed
Washed with water to expose defects
A musty smell on opening panels most likely indicates:
Lead paint
Fungus/dampness
Fuel vapor leak only
Moisture will tend to accumulate:
At upper wing skins
At lowest points of enclosed structures
Near leading edges only
When cutting access holes in plywood:
Use a trepanning tool; avoid excessive pressure
Use a cold chisel for speed
Make sharp square corners
After cutting access holes, edges should be:
Left rough for better paint adhesion
Smoothed with fine glass paper
Sealed with epoxy only
When inspecting a glue line, coatings should be:
Left on to avoid damage
Scraped until bare wood and glue line are visible
Burned off carefully
Timber shrinkage can result in:
Stronger glue lines
Loosened fittings/bolts and wood fiber damage
Self-healing joints
Evidence of water penetration in wood includes:
Bright white patches
Dark discoloration/grey streaks along grain
Orange peel surface
Typical correct moisture content for aircraft timber is:
8% ±1
15% ±2
25% ±2
Grain inclination limits for spruce: Grade A and Grade B respectively:
1 in 10; 1 in 8
1 in 15; 1 in 12
1 in 20; 1 in 15
“Dote” is:
A harmless resin pocket
A serious inherent disease at the tree base; affected wood rejected/burned
Mild discoloration only
Ring-shakes are usually caused by:
Frost after heavy rainfall
UV exposure
Over-sanding
Compression-shake appears as:
Random pinholes
Thin wavy line across a cross-section (partial fracture risk)
Straight split only
Clusters of pin-knots should be:
Accepted if small
Rejected
Filled with glue
Synthetic resin adhesives are usually supplied as:
Single-part only
Two-part
Three-part systems
Liquid resin is typically mixed with:
Solvent only
Hardener
Plasticiser
“Maturation time” refers to:
Shelf life in storage
Specified delay between mixing and application before use
Curing time after clamping
Adhesive should generally be applied to:
One surface only
Both surfaces
Neither (use capillary action)
Adhesive joint control testing (vice-lever break) should show at least:
25% wood fiber failure
50% wood fiber failure
75% wood fiber failure on fracture faces
For wet tests indicating cure, immerse samples in water about 15–25°C for:
2–3 hours
24 hours (after conditioning 2–3 weeks)
7 days immediately after bonding
The yarns running lengthwise in fabric are the:
Weft
Warp
Bias
The non-fraying edge of fabric is called:
Fillet
Selvedge
Boltrope
Natural fabrics (cotton/linen) require replacement primarily due to:
Salt corrosion only
UV, mildew/fungus, pollution
Fuel resistance loss only
Artificial fabrics commonly used include:
Kevlar only
Polyester and glass-fibre
Nylon and aramid only
Hand-sewing threads/cords should be coated with:
Epoxy
Beeswax
Grease
Stringing is commonly done with:
Linen cord, single strands (doubled allowed in repairs)
Steel wire
Polyester straps
Standard rib-stitch pitch is typically:
25 mm
75 mm
150 mm
On marine aircraft, shrouded eyelets are used to:
Increase airflow
Prevent sea spray entry
Improve appearance
Wooden (celluloid) frame panels are doped on; drawback is:
Heavy weight
New doped patch needed after each inspection
Cannot be sealed
Zip (“V” twin fastener) panels are best where:
Access is rare
Frequent inspection/servicing is needed
High-temp areas exist
Spring panel consists of:
Steel screw only
Circular plastic ring + dished light-alloy cover clipped in
Velcro flaps
Two common dope film bases are:
Epoxy and polyurethane
Cellulose nitrate and cellulose acetate butyrate
Vinyl and acrylic
First priming coat for natural fabrics is generally:
Butyrate
Nitrate dope
Aluminium dope
Fungicide is required in the first coat for:
Polyester fabric
Natural fabrics
Glass-fibre fabric
Aluminium dope’s key purpose is to:
Improve gloss only
Make fabric light-proof against UV
Reduce weight
Retarder (anti-blush) thinners are used to:
Speed drying
Slow drying to prevent moisture condensation/blushing
Increase film hardness immediately
Polyester-fibre fabric is primarily tautened by:
Dope tautening
Heat shrinking
Water shrinking
First coat for polyester should be:
Nitrate dope thinned
Butyrate only
Aluminium dope
