Aircraft Annual Inspection: Scope, Discrepancies and Owner Preparation

For many US general aviation aircraft, the annual inspection is the recurring inspection required within the preceding 12 calendar months. It is an airworthiness determination against the applicable rules and aircraft data, not a fixed-price maintenance package and not a promise that no discrepancies will be found.

This article replaces an earlier version that published unsupported labour prices and gave checklist items, mechanic-selection advice and maintenance recommendations without retained evidence. The revision covers standard-category aircraft using the annual-inspection path under Part 91. Experimental condition inspections and aircraft on progressive, continuous or other approved programmes need their own controlling documents.

Which aircraft need an annual inspection

14 CFR 91.409 generally prohibits operation unless, within the preceding 12 calendar months, the aircraft has received an annual inspection in accordance with Part 43 and has been approved for return to service by an authorised person.

The rule also separates several cases:

• aircraft used to carry a person for hire, or provided for flight instruction for hire, can also be subject to the 100-hour requirement;
• a 100-hour inspection cannot replace an annual unless an annual-authorised person performs it and records it as an annual;
• progressive inspection programmes have their own approval and completion framework; and
• large airplanes, turbojet multiengine airplanes, turboprop multiengine airplanes and certain turbine rotorcraft operate under the programme choices in 91.409(e) and (f).

An owner should identify the aircraft's actual inspection programme before treating “annual” as the whole answer.

Inspection and repair are different scopes

The annual establishes whether the aircraft meets the applicable airworthiness requirements at the time of inspection. Corrective work can be needed before an approval for return to service, but it should be described separately from the inspection labour.

A useful work authorisation distinguishes:

1. the inspection scope and base charge;
2. opening, cleaning, access and reassembly assumptions;
3. scheduled maintenance requested at the same visit;
4. troubleshooting requested for known defects;
5. the approval threshold for additional work; and
6. the process for documenting discrepancies not corrected during the visit.

That separation lets the owner understand whether a cost arose from performing the inspection, completing planned maintenance or correcting a newly identified condition.

What sets the inspection scope

Part 43 Appendix D provides the minimum scope and detail for annual and 100-hour inspections. It calls for opening or removing necessary inspection plates, access doors, fairings and cowlings and cleaning the aircraft and engine as required before inspecting the listed areas and systems.

The list covers the fuselage and hull, cabin and cockpit, engine and nacelle, landing gear, wing and centre section, empennage, propeller, radio and electronic equipment and other installed items. The aircraft's current manufacturer instructions, type design, alterations, airworthiness directives and operating history can add aircraft-specific work and evidence.

FAA Advisory Circular 20-106 is written to familiarise owners and pilots with inspection techniques. The FAA expressly states that it does not qualify a reader to make airworthiness determinations.

That is the practical boundary: an owner can prepare records, identify symptoms and agree commercial terms, but the authorised person makes the inspection finding and the appropriate certificated person performs or supervises maintenance within their privileges.

Two possible inspection outcomes

14 CFR 43.11 sets the inspection-record requirements. The record must identify the type and extent of inspection, date, aircraft time in service and the person approving or disapproving the aircraft for return to service.

The practical outcomes are:

• approved for return to service: the authorised person records that the aircraft was inspected and found airworthy; or
• not approved: the authorised person records that finding and provides the owner or lessee with a signed and dated discrepancy or unairworthy-item list.

An annual is therefore not incomplete merely because discrepancies exist. The inspection can reach a documented conclusion even when the aircraft is not yet approved to fly. Corrective work and the later return-to-service entry must then be handled by appropriately authorised people using acceptable or approved data as required.

Prepare the evidence before the aircraft arrives

FAA guidance on owner and mechanic responsibilities emphasises that the owner or operator remains responsible for airworthiness and should understand maintenance documentation and communicate effectively with the shop.

Before the visit, assemble a dated package containing:

• airframe, engine, propeller and appliance records;
• the current inspection status and last annual entry;
• total time and time-since-overhaul records where applicable;
• the current status and method of compliance for applicable airworthiness directives, including recurring actions;
• life-limited-part status;
• major repair and alteration records;
• aircraft flight manual supplements, equipment lists and weight-and-balance changes; and
• a written list of observed defects, intermittent indications and recent maintenance.

The FAA's active AC 43-9D explains current maintenance record-making and record-keeping requirements under Parts 43 and 91.

Missing records are not merely an administrative inconvenience. They can prevent a reviewer from establishing current inspection, airworthiness-directive, alteration or life-limit status.

Agree how discrepancies will be handled

Before work begins, decide who may authorise additional labour and parts, at what amount a new approval is required, and how urgent findings will be communicated.

A discrepancy discussion should identify:

1. the observed condition;
2. the rule, approved data, manufacturer limit or instruction that makes it significant;
3. whether it prevents approval for return to service;
4. the proposed corrective action and data source;
5. parts, outside work and schedule dependencies; and
6. the maintenance-record entry that will close the work.

Photographs can help explain a condition, but they do not replace measurements, records or the authorised person's finding.

Annual, 100-hour and condition inspection are not synonyms

The terms are often collapsed in casual discussion:

Inspection	Common trigger	Important distinction
Annual	Preceding 12 calendar months under 91.409(a)	Requires annual-inspection authority and an annual record entry
100-hour	Certain for-hire passenger or provided-flight-instruction use under 91.409(b)	May be exceeded only as the rule permits for travel to the inspection location; excess time counts toward the next interval
Progressive	Approved programme under 91.409(d)	The complete cycle and programme records control due status
Experimental condition inspection	Aircraft operating limitations and applicable certificate privileges	It is not automatically a standard-category annual inspection

Aircraft type, certificate category and operation determine which row applies.

The owner handover record

At completion, retain:

• the signed inspection entry;
• the discrepancy list if the aircraft was not approved;
• separate maintenance entries for corrective work;
• invoices that identify parts and outside services;
• updated airworthiness-directive and life-limit status; and
• any revised weight-and-balance, flight-manual supplement or alteration record.

Before flight, verify that the aircraft has the required approval-for-return-to-service entry. The FAA's return-to-service safety brief specifically warns pilots to check for that signed entry after maintenance.

The 2026 bottom line

An annual inspection is a regulated airworthiness review with a defined record outcome. It is not a generic tune-up, a guaranteed invoice or permission for an owner to decide which airworthiness findings count.

The owner's strongest preparation is documentary: identify the correct inspection programme, organise the continuing-airworthiness record, disclose known defects, define the approval process for extra work and retain the final entries.

Sources reviewed

• 14 CFR 91.409: Inspections
• 14 CFR 43.11: Inspection records
• FAA AC 20-106: Aircraft Inspection for the General Aviation Aircraft Owner
• FAA owner and mechanic roles
• FAA AC 43-9D: Maintenance Records and FAA Form 8130-3
• FAA approval-for-return-to-service brief