Non-Metallic Structures & Composites
Non-Metallic Structures & Composites is a core knowledge area on the AMT — Airframe FAA written exam. This hub collects our 16 in-depth, ACS-aligned non-metallic structures & composites articles — each written in plain English and grounded in the official FAA handbooks. Work through them below, then drill the topic with practice questions.
Carbon Fiber vs Aramid vs Fiberglass Reinforcement Materials
Carbon fiber, aramid, and fiberglass are the three dominant reinforcement materials in aircraft composite structures, each offering distinct trade-offs in strength, weight, stiffness, and repairability that every AMT must understand.
Fiberglass Layup Techniques and Fabric Orientation
Fiberglass layup techniques and fabric orientation are fundamental composite skills for AMT airframe technicians, directly affecting structural strength, weight, and airworthiness of repaired or fabricated composite components.
Wet Layup vs Prepreg Composite Fabrication Methods
Wet layup and prepreg are the two dominant composite fabrication methods in aircraft structures; understanding their materials, processes, quality factors, and tradeoffs is essential for AMT airframe certification.
Vacuum Bagging Process and Debulking Procedures
Vacuum bagging compacts composite layups by drawing a uniform pressure across the laminate, removing trapped air and excess resin to produce strong, void-free structures. Debulking at intermediate stages ensures proper consolidation before final cure.
Autoclave Curing Cycles and Pressure-Temperature Profiles
Autoclave curing transforms raw composite layups into finished structural parts by applying precisely controlled heat and pressure simultaneously; mastering the cycle parameters is essential for airworthy repairs and manufacturing.
Honeycomb Core Materials: Nomex, Aluminum, and Foam Types
Honeycomb core materials—including Nomex aramid fiber, aluminum, and various foam types—provide exceptional strength-to-weight ratios in aircraft sandwich structures and are essential knowledge for AMT Airframe certification.
Sandwich Structure Construction and Core-to-Skin Bonding
Sandwich structure construction pairs thin, strong face skins with a lightweight core to achieve exceptional stiffness-to-weight ratios; understanding core types, bonding mechanics, and failure modes is essential for AMT airframe certification.
Thermoset vs Thermoplastic Resin Systems in Aviation
Thermoset and thermoplastic resins are the two fundamental polymer families used in aviation composites, each with distinct curing chemistry, repairability, and structural performance characteristics that AMTs must understand.
Non-Destructive Inspection Methods for Composite Structures
Non-destructive inspection (NDI) methods allow technicians to detect hidden damage in composite airframe structures without cutting or removing material, ensuring structural integrity while preserving the part.
Tap Testing and Coin Testing for Delamination Detection
Tap testing and coin testing are fundamental non-destructive inspection techniques used by AMTs to detect delamination and disbonds in composite and honeycomb airframe structures by listening for changes in acoustic response.
Composite Damage Classification: Scratches, Delamination, and Impact Damage
Composite airframe damage falls into distinct categories—scratches, delamination, and impact damage—each requiring specific inspection and repair methods to restore structural integrity.
Scarfed and Stepped Repair Techniques for Composite Skins
Scarfed and stepped repairs restore structural integrity to damaged composite aircraft skins by creating large bonding surfaces that redistribute load — understanding the geometry, ratios, and process is essential for AMT certification.
Potted Insert and Fastener Installation in Honeycomb Panels
Potted inserts and mechanical fasteners allow honeycomb sandwich panels to carry concentrated loads without crushing the core, using resin-filled cavities and specialized hardware matched to the panel construction.
Moisture and Contamination Effects on Composite Bond Strength
Moisture and contamination are leading causes of composite bond failure in aircraft structures; understanding how they degrade adhesion helps AMTs prevent dangerous hidden damage during repair and inspection.
Composite Material Storage, Shelf Life, and Handling Requirements
Composite prepregs and repair materials degrade rapidly when stored incorrectly; understanding shelf life limits, freezer storage, and proper handling prevents hidden structural failures in aircraft.
Lightning Strike Protection in Composite Airframe Structures
Composite airframes lack the natural electrical conductivity of metal, requiring dedicated lightning strike protection systems to safely conduct massive electrical currents and prevent structural damage or fuel ignition.
More AMT — Airframe subjects
Articles are original summaries grounded in the public-domain FAA handbooks and cite their source. ACS-aligned study aids — not a substitute for the official handbooks or regulations.