Aircraft Structural Inspection Techniques Flashcards

What inspection method is most commonly used to detect surface cracks in metal structures?

Answer: Dye penetrant inspection

Dye penetrant inspection (DPI) is the most commonly used non-destructive testing (NDT) method for detecting surface cracks in non-porous metal structures. A liquid penetrant seeps into surface-breaking defects, and a developer then draws it out, making the flaws visible to the inspector.

Which technique is best suited for detecting internal flaws in composite materials?

Answer: Ultrasonic inspection

Ultrasonic inspection is best suited for detecting internal flaws, such as delaminations, voids, and inclusions, within composite materials. This non-destructive technique uses high-frequency sound waves that travel through the material and reflect off discontinuities, allowing technicians to map the internal structure and identify hidden defects.

What is a common sign of corrosion in aluminum aircraft structures?

Answer: Surface bubbling and pitting

A common sign of corrosion in aluminum aircraft structures is the appearance of surface bubbling and pitting. This occurs as corrosion products form beneath the paint, lifting it (bubbling), and as the metal itself degrades, creating small depressions or holes (pitting) on the surface.

Which inspection document outlines intervals for structural checks?

Answer: Maintenance manual

The aircraft's maintenance manual is the primary inspection document that outlines the specific intervals and detailed procedures for structural checks and other maintenance tasks. Provided by the manufacturer, it ensures that all inspections and repairs comply with design specifications and airworthiness requirements.

How are hidden cracks in ferromagnetic materials typically found?

Answer: Magnetic particle inspection

Hidden cracks in ferromagnetic materials (like steel) are typically found using magnetic particle inspection (MPI). This non-destructive testing method involves magnetizing the part and applying fine magnetic particles, which accumulate at any surface or near-surface discontinuities, making the cracks visible.

Why is borescope inspection useful in aircraft maintenance?

Answer: To view internal structural areas

Borescope inspection is highly useful in aircraft maintenance because it allows technicians to visually inspect internal structural areas and components without extensive disassembly. This optical instrument can access confined spaces, such as inside engines or wing structures, to check for damage, corrosion, or foreign objects, saving significant time and cost.