What is the typical sequence for a shop overhaul from teardown to final acceptance?

• A. Disassembly with marking; NDT; final inspection; certification.
• B. Disassembly with marking, preliminary inspection, dimensional measurements, NDT, component repair/replacement, cleaning/coating, reassembly, shop test run, final inspections, certification.
• C. Disassembly; reassembly; certification.
• D. Shop test run before teardown.

Answer: (B)

The sequence reflects a deliberate, traceable workflow that turns teardown into a certified, serviceable engine. Start with disassembly with marking to preserve part identity and orientation, which keeps reassembly accurate and maintains traceability across the overhaul. Then a preliminary inspection quickly flags obvious damage and guides what needs closer scrutiny. Dimensional measurements follow to quantify wear and determine if parts can be reused or require repair or replacement, based on established limits. Non-destructive testing is applied to reveal hidden flaws in critical areas that aren’t visible to the eye.

With those findings, repairs or replacements are performed as needed, and components are cleaned and coated to remove contaminants and protect surfaces before reassembly. Reassembly then proceeds under strict procedures, with correct clearances and torque specs to restore proper fit and function. A shop test run checks operability, performance, and behavior under controlled conditions to catch any issues before final acceptance. Final inspections verify that all workmanship and specifications are met and that documentation is complete. The process concludes with certification, documenting compliance, traceability, and airworthiness for return to service.

Why this order matters: each step builds on the previous one. You identify what’s usable, discover hidden flaws, restore integrity, and verify that all systems perform as intended before you formally certify the overhaul. Skipping or omitting steps can miss defects, compromise fit and function, or leave gaps in traceability.