Conducting an airframe inspection

Six procedures, in the order the work happens: establish scope, build the instrument, inspect the records, inspect the aircraft, decide, record.

Procedure 1 — Establish the scope (S6, K5)

Before touching the aircraft.

1. Determine which inspection is due and under what rule — 100-hour, annual, progressive, or a manufacturer's program.
2. Read the scope: part 43 appendix D for a 100-hour, plus the manufacturer's inspection program.
3. Search for ADs — airframe, engine, propeller and appliance (GEN-I Procedures Procedure 3). Note any now due.
4. Check life-limited parts against current time and cycles.
5. Check the manufacturer's recurring-maintenance intervals for tasks that fall due at this 100-hour. A 300-hour filter replacement is not in appendix D, but it may fall due at this one. Compare each interval with the time since that task was last done, from the records.
6. Check service bulletins and ICA the owner has adopted or that are mandatory.
7. Check for special inspections triggered by events in the record — hard landing, lightning strike, overspeed, unusual occurrence.
8. Write the scope down.

Check — state what is in scope and what is not, and why. Both directions are failures (AF-D Concepts §2), and a scope you cannot articulate is one you will drift outside.

Procedure 2 — Produce the checklist (S5)

1. Start from appendix D's scope and the manufacturer's program.
2. Organize by area of the aircraft, in the order you will physically work it, so the inspection flows.
3. For each item: what to inspect, what to look for, and against what limit. "Inspect fuselage" is not a checklist item.
4. Add the additional items from Procedure 1.
5. Include space to record findings, not just ticks.
6. Reference the source of the scope on the checklist itself.

Check — hand the checklist to someone else and ask whether they could conduct the inspection from it. If they need to ask what "check controls" means, the item is not written yet.

Failure — a checklist that silently narrows the inspection. The checklist is one person's rendering of the scope, and a bad rendering is how a required item goes uninspected while the paperwork says otherwise (AF-D Concepts §2).

Procedure 3 — Inspect the records (S1, part 1)

1. Establish current time in service and the basis for it.
2. Verify the inspection status of everything with a clock: airframe, engine, propeller, appliances, ADs, life-limited parts (GEN-I Procedures Procedure 4).
3. Check AD compliance history — every applicable AD, its method, and whether recurring ones are current.
4. Check the weight and balance record is current and matches the equipment list (GEN-C Procedures Procedure 9).
5. Look for previous major repairs and alterations and their Form 337s. They change what you are inspecting.
6. Note anything missing — gaps in the record are a finding.

Check — can you account for the aircraft's history without gaps? A missing period is not an absence of maintenance; it is an absence of evidence, and it is a finding to report to the owner.

Procedure 4 — Inspect the aircraft (S1, S2, S7)

1. Work the checklist, in order, recording as you go rather than afterwards.
2. Apply the inspection technique from GEN-K Procedures Procedure 2 — clean, light, aided vision, a pattern, known failure modes.
3. Record findings with enough detail to act on: what, where, how big, measured against what limit.
4. Inspect seats and restraints including TSO markings (S7) — the marking is what establishes the article is approved.
5. Do not repair as you go unless the discrepancy is trivial and within your scope. Repairing during an inspection loses track of what was found.

Check — every checklist item must have an outcome recorded, not just the ones with findings. A blank line is ambiguous: it may mean satisfactory, or it may mean not inspected.

Procedure 5 — Determine airworthiness (S1, part 3)

1. Review every finding against approved data limits.
2. Classify: within limits, repairable, or unairworthy as found.
3. For anything requiring repair, determine major or minor (GEN-I Procedures Procedure 1).
4. Make the determination: airworthy, or not.
5. If not airworthy, prepare the list of discrepancies for the owner. That list is a required output, not a courtesy.

Check — the determination is binary and it is yours. "Airworthy except for" is not a determination. Either the aircraft meets its type design and is in condition for safe operation, or it does not and you provide the list.

Procedure 6 — Make the record entry (S3)

Per GEN-I Procedures Procedure 7:

1. Type and scope of the inspection, with its reference.
2. Date and time in service.
3. The determination — airworthy, or unairworthy with the discrepancy list provided.
4. Signature, certificate number, kind of certificate.

Check — read your entry as though you are an inspector in ten years. Does it say what inspection was done, to what scope, on what date, at what time, and what was concluded? If any of the five is missing, it is not finished.

Failure — the entry written from memory at the end of the day. Findings recorded during the inspection are accurate; findings recalled afterwards are not (GEN-I Concepts §5).

The checks, collected

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