12.3 Airworthiness Certificates, Required Documents, Marking & Registration

12.3 Airworthiness Certificates, Required Documents, Marking & Registration

[!NOTE] First question on any inspection: what certificate does this aircraft hold? The answer determines whether Part 43 applies at all (Section 2.1), whether the aircraft needs an annual inspection or a condition inspection, who may sign it off, and which set of operating limitations governs. Get this wrong and every subsequent judgment is built on sand.

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Certificate Types and the Forms They Are Issued On

Why the standard certificate has no expiration date is a favorite exam point. The certificate itself states the condition on which it remains effective: as long as maintenance, preventive maintenance, and alterations are performed in accordance with Parts 43 and 91 and the aircraft is registered in the United States. So an overdue annual does not "expire" the certificate — it makes the certificate ineffective because the maintenance condition is unmet. That distinction explains why an IA never confiscates or voids an airworthiness certificate (Section 8.2): the certificate's effectiveness is a function of the aircraft's condition and records, not of a piece of paper being surrendered.

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Documents Required Aboard: 14 CFR 91.203

Section 91.203 requires that a civil aircraft not be operated unless it has within it:

1. An appropriate and current airworthiness certificate, and
2. An effective U.S. registration certificate (or the specified equivalents for aircraft awaiting registration).

The airworthiness certificate must be displayed at the cabin or cockpit entrance so that it is legible to passengers or crew. The registration certificate need only be carried aboard, not displayed.

The common industry mnemonic ARROW captures what an IA and a pilot both check:

Note the qualification on the radio station license: it is an FCC requirement tied to international operation, not a domestic Part 91 requirement. An exam answer that lists it as universally required is overstated.

Flight manual supplements matter to an IA specifically: when an STC or major alteration produces an Airplane Flight Manual Supplement, that supplement becomes part of the operating limitations required by § 91.9 and must be in the aircraft (Section 4.3). An installed STC whose AFMS is sitting in a shop file is a discrepancy.

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Which Inspection Does This Aircraft Need?

The certificate determines the inspection, and this is where candidates most often over-generalize:

The experimental condition inspection is worth spelling out because the exam asks it directly. An amateur-built aircraft holding an experimental certificate requires a condition inspection, not an annual inspection. Its operating limitations, issued under § 91.319, commonly require the inspection to be performed using the scope and detail of Part 43 Appendix D, and to be recorded with a specific statement that the aircraft is in a condition for safe operation. As Section 2.1 explains, that procedural reference to Appendix D does not bring the aircraft under Part 43's maintenance rules — § 43.1(b)(1) still excludes it unless a different kind of airworthiness certificate was previously issued for that aircraft.

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Part 45: Identification and Registration Marking

14 CFR Part 45 governs two distinct things an IA verifies:

Identification Plate — Subpart A

Aircraft, aircraft engines, propellers, and certain appliances must be identified by a fireproof plate bearing the builder's name, model designation, and serial number, among other data. For aircraft the plate must be secured so it is not likely to be defaced or removed during normal service, or lost or destroyed in an accident, and it must be accessible.

For the IA, the identification plate is the authoritative source of the make, model, and serial number used for every data sheet lookup in Section 12.2 — not the registration certificate, not the logbook cover, and not the paint on the tail.

Removal or alteration of identification data is restricted: a person may not remove, change, or place identification information without FAA approval, and § 45.16 governs the marking of life-limited parts in connection with § 43.10 (Chapter 8).

Nationality and Registration Marks — Subpart C

U.S.-registered aircraft display the "N" prefix followed by the registration number, in the size and location prescribed by Part 45. The marks must be painted on or affixed by other permanent means, and must be legible, of contrasting color, and kept clean and unobscured.

Registration — Part 47

Registration is a Part 47 function performed by the FAA Aircraft Registration Branch, which issues AC Form 8050-3, Certificate of Aircraft Registration. Two practical points for an IA:

• The owner name and address on Item 2 of FAA Form 337 must match the registration certificate (Section 5.2), which is also why the registry validates a submitted Form 337 by matching the registration mark against the serial number.
• Registration must be current. An aircraft whose registration has lapsed cannot be legally operated regardless of its mechanical condition, and § 91.203(a)(2) puts the registration certificate among the documents required to be aboard.

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What the IA Verifies Before Touching the Aircraft

[ ] Airworthiness certificate present, appropriate to the operation, displayed at
    the cabin or cockpit entrance and legible
[ ] Registration certificate present and current
[ ] Identification plate present, legible, and matching the records
[ ] Registration marks correct, legible, contrasting, unobscured
[ ] Approved flight manual / operating limitations aboard, including every AFMS
    for every installed STC
[ ] Current weight and balance data and equipment list aboard
[ ] Certificate type matches the inspection being performed
    (annual vs. condition inspection vs. program)

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High-Yield Exam Traps

• A standard airworthiness certificate has no expiration date; it remains effective while maintenance is performed under Parts 43 and 91 and the aircraft stays U.S. registered.
• The airworthiness certificate is displayed; the registration certificate is merely carried.
• An amateur-built experimental aircraft gets a condition inspection, not an annual, and no IA is required to sign it.
• Special airworthiness certificates and special flight permits are issued on FAA Form 8130-7; the standard certificate is FAA Form 8100-2.
• The identification plate, not the paperwork, is the source of the serial number used for data sheet lookups.
• A missing AFMS for an installed STC is a discrepancy under § 91.9.