CAT Maintenance Tools and Equipment 2

Question 1

What is the primary use of dye penetrant inspection (DPI) in aerospace maintenance?

Accepted Answer

To detect surface-breaking cracks and defects in non-porous materials

Answer

Dye penetrant inspection uses a colored or fluorescent penetrant that seeps into surface-breaking defects, revealing cracks and porosity on the surface of non-porous materials after developer is applied.

Question 2

When is Magnetic Particle Inspection (MPI) preferred over dye penetrant for detecting defects?

Accepted Answer

When inspecting ferromagnetic materials for both surface and near-surface defects

Answer

MPI is preferred for ferromagnetic materials (iron, steel, nickel alloys) because it detects both surface and near-surface discontinuities using magnetic fields and iron particles.

Question 3

What type of NDT method uses high-frequency sound waves to detect internal defects in aircraft structures?

Accepted Answer

Ultrasonic Testing (UT)

Answer

Ultrasonic Testing sends high-frequency sound waves through material and analyzes reflections to detect internal voids, cracks, inclusions, and delaminations in both metallic and composite structures.

Question 4

What is the correct application sequence for dye penetrant inspection?

Accepted Answer

Clean surface → Apply penetrant → Dwell time → Remove excess → Apply developer → Inspect

Answer

Proper DPI sequence is: clean and dry the surface, apply penetrant, allow dwell time for penetration, remove excess penetrant, apply developer to draw out penetrant, then inspect under appropriate lighting.

Question 5

What is the primary advantage of eddy current testing (ECT) in aerospace inspections?

Accepted Answer

It can detect cracks and corrosion in conductive materials through coatings and paint without surface preparation

Answer

Eddy current testing induces electromagnetic currents in conductive materials and detects disruptions caused by cracks or corrosion, often through surface coatings without requiring paint removal.

CAT - Certified Aerospace Technician Practice Test

CAT - Certified Aerospace Technician Practice Test

CAT Maintenance Tools and Equipment 2