Airframe Systems & Structural Maintenance Flashcards
7 cards from real ACS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Airframe Systems & Structural Maintenance flashcards as text
Which NDT method is BEST suited for detecting subsurface delaminations in a composite honeycomb sandwich structure?
Answer: Tap test or ultrasonic through-transmission
A coin tap test or ultrasonic through-transmission is used to detect subsurface delaminations in composite honeycomb panels, while dye penetrant only finds surface defects and magnetic particle requires ferrous material.
What is the correct procedure when stop-drilling a crack in aluminum aircraft skin?
Answer: Drill the hole just ahead of the visible crack tip
The stop-drill hole must be placed just ahead of (beyond) the visible crack tip to eliminate the stress concentration at the crack tip and arrest crack propagation.
When replacing aircraft transparent enclosures (acrylic), the fastener holes should be:
Answer: Oversized to allow for thermal expansion of the acrylic
Acrylic plastic has a high coefficient of thermal expansion, so fastener holes must be oversized to prevent cracking as the material expands and contracts.
Which statement about aircraft control cable tension is correct?
Answer: Tension must be set at the temperature specified, with correction applied for ambient temperature using a rigging chart
Control cable tension varies with temperature; a rigging chart must be used to apply temperature corrections so final tension is correct across the operating temperature range.
A mechanic finds exfoliation corrosion on an aluminum alloy wing spar cap. What action is required?
Answer: Clean, treat, and determine if remaining material meets minimum thickness per SRM
Exfoliation corrosion causes layer-by-layer material loss; the mechanic must clean, treat, measure the remaining material, and compare it to the SRM minimum thickness allowable to determine airworthiness.
What is the minimum bend radius for aluminum alloy sheet when forming a repair part?
Answer: As specified in the aircraft SRM or manufacturer's structural repair data
Minimum bend radius depends on alloy type, temper, and thickness, and must be obtained from the aircraft SRM or manufacturer's structural repair data, not a universal rule.
When bonding a composite repair patch using a heat blanket cure, what is a critical parameter to monitor throughout the cure cycle?
Answer: Temperature uniformity across the repair area and pressure applied by vacuum bag
Uniform temperature distribution and adequate bag pressure (typically 25–30 inHg vacuum) are critical during heat-blanket cure to ensure proper resin flow, consolidation, and adhesion throughout the patch.