Aircraft Liens and the International Registry
For aircraft that fall within the Cape Town Convention, filing in the federal registry is only half the job. A second, entirely separate international registration decides priority — and a lender who files in one place has protected itself against some claimants and not others.
What this report covers
- Federal recording makes a security interest effective against third parties who deal with the aircraft domestically.
- The international registry governs priority between international interests in aircraft that fall within the convention's scope.
- Registration on the international registry is consent-based and electronic, and priority runs from the moment of registration.
- State-law mechanic's and repair liens can attach without any filing and can take priority over a recorded lender.
- A release is as important as the original filing: an unreleased lien blocks a sale years after the debt was paid.
A lender financing an aircraft faces a question that does not arise with a car or a house: which register decides who gets paid first. The answer depends on the aircraft, and getting it wrong produces a security interest that is perfectly valid and second in line.
The federal layer
Security instruments are recorded against the aircraft in the same federal registry that holds the ownership record and the chain of bills of sale. Recording is what makes the interest effective against people who later deal with the aircraft: an unrecorded security agreement binds the borrower who signed it and does little against a subsequent purchaser or lender who did not know of it.
The practical rules that follow:
- Priority is a function of the order documents reach the registry, not of when they were signed.
- Filings are indexed against the aircraft and against components with their own records, so engines and propellers can carry separate encumbrances.
- A release must itself be recorded. Payment alone does not clear the record.
When a second registry applies
For aircraft within the Cape Town Convention's scope, an international registry sits alongside the federal one and governs priority between international interests. The scope is defined by size rather than by use: airframes, engines and helicopters above defined thresholds are covered, and smaller aircraft are not. The pattern is familiar from other mobile assets: a federal register that establishes an interest against the world sitting above a state system that never sees it, exactly as a preferred ship mortgage recorded against a documented vessel operates above state titling.
| Federal recording | International registry | |
|---|---|---|
| Covers | All US civil aircraft | Aircraft objects above the convention thresholds |
| What is filed | The document itself | Electronic notice of an interest |
| Priority runs from | Filing at the registry | Moment of registration |
| Requires | Executed instrument | Consent of the party against whom it registers |
| Searchable by | Aircraft and owner | Manufacturer, model and serial number |
The registration is electronic, consent-based and continuous — priority runs from the moment of registration rather than from a filing date. That makes sequencing at a closing genuinely tight, and it is why transactions on covered aircraft are handled by parties with registry accounts and established procedures rather than improvised.
A lender who records federally but does not register internationally on a covered aircraft holds an interest that is good against domestic claimants and subordinate to an international interest registered by someone else. The reverse gap exists too. On a covered aircraft, both filings are the standard, not alternatives.
The liens that never appear in either register
The claims most likely to surprise a buyer are the ones that arise by operation of state law and require no filing at all.
Possessory repair liens. A maintenance facility that holds the aircraft and is owed for work on it can generally retain it until paid, and can foreclose if it is not. The lien exists because the shop has possession; nothing is filed.
Statutory mechanic's liens. Several states provide for a recorded lien for labor and materials supplied to an aircraft, sometimes with priority over prior recorded interests. These do appear in the record if properly filed, but the filing rules are state-specific and easy to miss on a search framed only around the federal registry. The statutes are built on the same architecture as their construction counterparts, with short windows measured from the last day of work and, in several states, a preliminary notice that has to reach the owner before any lien can attach — the notice discipline that defeats more liens than any substantive defense. An owner served with one of those notices by an engine shop is being told something about the shop's payment position that a search will not reveal for months.
Storage and hangar liens. Unpaid hangar rent produces a claim on the same possessory logic in many states.
The buyer's protection against all three is documentary rather than registrarial: paid invoices from the maintenance facility, a hangar account statement, and a warranty from the seller with substance behind it. A federal record search will not surface any of them, and the gap is the same one buyers face in states that do not title vessels at all, where the substitute for a register is a paper trail and the standing of the person who signed it.
What enforcement looks like
A secured lender enforcing against an aircraft moves faster than one enforcing against real property, because the collateral moves. The steps in an ordinary default:
- Locate the aircraft — flight tracking and hangar records make this easier than it once was.
- Take possession, either voluntarily or through a court order, depending on the state's self-help rules.
- Ground it, which for a covered aircraft may include a deregistration authorization lodged in advance.
- Address competing claims, including any possessory lien of the facility holding it.
- Sell, and account for the proceeds in the order priority requires.
For aircraft within the convention, the deregistration and export remedies are the substantive difference: a recorded irrevocable authorization allows the creditor to procure deregistration without the debtor's further cooperation, which is precisely the leverage that made the convention worth ratifying.
Closing the file properly
The most common lien problem is not a fraudulent one. It is an old, paid, unreleased interest that nobody thought about for a decade until a sale surfaced it. Clearing it means finding the lender, or its successor, or its liquidator, and obtaining a release from an entity that may no longer have anyone who remembers the loan.
Two habits avoid this entirely: obtain and record the release at the moment of payoff rather than trusting that the lender will file it, and confirm the record is clear afterwards. Both take a day. The alternative is a title problem discovered at a closing, where the buyer's money is waiting and the only person who can solve it is not answering.
Sources
- Cornell Legal Information Institute — 49 U.S.C. 44107, Recordation of Conveyances
The federal recording system for security instruments against aircraft.
- Cornell Legal Information Institute — 49 U.S.C. 44108, Validity of Conveyances
The priority effect of recording, and the position of unrecorded interests.
- eCFR — 14 CFR Part 49, Recording of Aircraft Titles and Security Documents
The mechanics of lodging and releasing a security document.
- UNIDROIT — Cape Town Convention and Aircraft Protocol
The convention text defining international interests and the registry that records them.
- International Registry of Mobile Assets
The registry itself: registration types, consent requirements and searches.
- Cornell Legal Information Institute — Mechanic's Lien
The state-law possessory and statutory liens that arise without filing.
Questions readers ask
Does every aircraft fall under the international registry?
No. The convention's aircraft object definitions are keyed to size — airframes above a passenger or payload threshold, engines above a thrust or power threshold, and helicopters above a seating threshold. A light single-engine aircraft generally falls outside it entirely, so the federal record is the whole picture. Corporate jets, airliners and their engines generally fall inside it.
Can a repair shop hold my aircraft over an unpaid bill?
In most states, yes, and the lien can arise without any filing. Possessory repair liens are creatures of state law: the shop that has the aircraft and is owed for work on it can usually retain possession until paid, and can foreclose if it is not. Because they arise by operation of law, they do not appear in a federal record search, which is why a buyer asks for paid invoices as well as a title search.
How do I get an old lien released?
The lender executes a release and it is recorded against the aircraft. Where the lender has been acquired, dissolved or cannot be traced, the process becomes evidentiary — proof of payment, corporate succession documents, and in stubborn cases a court order quieting the record. This is why paying off an aircraft loan and confirming the recorded release are two separate tasks, and only the second one closes the file.
