Eight real diagnostic scenarios — from unexpected brittle fracture in cold weather to galvanic corrosion, weld cracking, hydrogen embrittlement, stress corrosion cracking, and composite delamination — each worked through symptoms, diagnosis, testing, and resolution.
Replacing a cracked part with an identical one and hoping it doesn't crack again is a guess dressed up as a repair. This module works through eight real diagnostic scenarios spanning mechanical, thermal, chemical, and manufacturing-related causes, each following the same structure: record the symptom precisely, form a diagnosis consistent with the physical evidence and nothing else, run a specific test that confirms or rules it out, and only then apply the fix that follows from a confirmed cause.
Every scenario here is built around at least two plausible causes that can present the same visible symptom — the same discipline this program's failure analysis, material selection, manufacturing, and testing modules were building toward, now applied to real field failures rather than a design calculation.