A turbine blade borescope inspection is only as good as the consistency behind it — the entry angle at each stage, the image capture sequence across every blade row, the criteria used to classify a mark as cosmetic versus a defect requiring action, and the discipline to compare every finding against a real baseline rather than memory. Skip a step or apply inconsistent judgment and a developing crack, coating spallation, or foreign object damage site can pass two or three inspection cycles before anyone flags it as a trend. This interactive checklist lays out the sequence an AI-assisted borescope inspection should follow from entry through final classification — check off each item as your team completes it — and where iFactory's turbine inspection tools fit into each stage.
The Complete AI Borescope Turbine Blade Inspection Checklist
Why a Checklist Matters More Than Experience Alone
Experienced inspection technicians develop strong instincts, but instinct is exactly the thing that varies from one person to the next and from one shift to another. A structured checklist does not replace technician skill — it removes the variability that skill alone cannot control, ensuring the same access points, the same image angles, and the same classification thresholds apply whether the inspection is being run by a twenty-year veteran or a technician six months into the role. That consistency is what makes cycle-over-cycle trend detection possible at all.
Stage 1 — Pre-Inspection Preparation
Stage 2 — Entry Angle and Capture Sequence
Consistency at this stage is what makes AI-based comparison possible in the first place — a model comparing this cycle's image against last cycle's baseline needs the blade photographed from a matching angle and distance, or the comparison introduces noise that masks real degradation.
Stage 3 — AI-Assisted Defect Classification
Severity Thresholds by Defect Category
| Defect Category | Low Severity | Medium Severity | High Severity | Typical Action at High |
|---|---|---|---|---|
| Crack Indication | Not detected | Sub-threshold length, monitor | Exceeds length or depth threshold | Remove from service |
| Coating Spallation | Isolated, small area | Multiple sites, moderate area | Substrate exposed over large area | Schedule recoat or replace |
| Leading Edge Erosion | Cosmetic only | Measurable profile change | Aerodynamic profile compromised | Engineering evaluation |
| Foreign Object Damage | Surface mark, no deformation | Minor deformation, no crack | Deformation with crack indication | Immediate escalation |
Want this checklist built into your own inspection workflow with automated severity scoring? Book a walkthrough to see it running on sample blade images.
Stage 4 — Engineering Review and Sign-Off
Stage 5 — Recordkeeping for the Next Cycle
Stage 6 — Fleet-Level Pattern Review
The final stage extends beyond a single unit's inspection cycle — reviewing whether a specific defect pattern is appearing consistently across multiple units of the same turbine model, which often points to a design, coating, or operating condition issue rather than an isolated maintenance concern for one unit.
Common Mistakes That Break Baseline Comparison
Every stage of this checklist ultimately supports one goal: making sure the image captured this cycle can be compared against the baseline image with confidence. That goal is easier to state than to consistently execute across dozens of blades and multiple stages during a time-pressured outage window, and a handful of recurring mistakes are responsible for most of the comparison failures plants run into. These are flagged separately below since they are pitfalls to watch for, not steps to check off.
Why the Fleet-Level Review Stage Often Gets Skipped — and Shouldn't
Stage six is the step most inspection programs treat as optional, largely because it requires pulling data across multiple units rather than focusing on the one unit currently in the outage bay. That is precisely why it matters. A single high-severity crack indication on one blade might reasonably be treated as an isolated maintenance item. The same crack indication appearing at the same stage position on three sister units within the fleet points toward something systemic — a coating batch issue, a design margin problem at that specific stage, or an operating condition common across those units that is accelerating a shared failure mode. Catching that pattern early, rather than treating each unit's finding in isolation, is often the difference between a scoped repair and a fleet-wide engineering investigation launched only after a unit actually fails.
Building this review into the standard checklist rather than leaving it as an ad hoc exercise means it happens every cycle rather than only when someone happens to notice a pattern informally. Plants that formalize this step typically assign it to the reliability engineering lead rather than the outage inspection technician, since it requires access to fleet-wide records that go beyond any single unit's outage file.
