FAA Aircraft Document Index — Lien, Release & Bill of Sale Filings

Check a list of N-numbers against the FAA Aircraft Registry Document Index and get back every conveyance document filed for recordation against each aircraft: security conveyances (liens), lien releases, repossessions, bills of sale, court documents — each with its FAA document ID, document type and receipt date.

Data comes from the FAA Civil Aviation Registry's own published Releasable Aircraft Database, refreshed every federal working day. No API key, no account.

Read this first: what this is, and what it is not

This is not a title search. The FAA Document Index is a rolling window of roughly the last 180 days of document receipts. A security conveyance recorded in 2019 and never released is not in this dataset at all, so a result of "no filings" here is not a statement that an aircraft is free of liens.

Every run returns the window's real measured start and end dates on every record, and results say this in words. For a full chain of title, order the aircraft record from the FAA or buy a title report from a title company.

What it is good for:

Job	How
Gap / date-down check at closing	Set sinceDate to your title report's cutoff and see everything filed since
Collateral monitoring	Run your loan book on a schedule, filter to S/A and REP, and get alerted when a competing security conveyance or a repossession lands
Release tracking	Confirm your REL was actually received in Oklahoma City, with the FAA document ID and receipt date
Filing confirmation	Confirm a bill of sale or registration filing reached the Registry, and when
Portfolio-scale screening	Up to 2,000 aircraft in one run against one file download

Why this beats reading the FAA's inquiry page yourself

The FAA's own Document Index Inquiry page shows each document more than once — typically two to three times. The index carries one row per document per party, and the FAA withdrew all party names under the 49 U.S.C. §44114 procedure for withholding personally identifiable information. What is left on screen is identical duplicate rows with nothing to distinguish them.

Measured on the live site and in the bulk file, same answer both ways:

N-number	Entries the FAA shows	Actual distinct documents
N100HY	6	2
N904AV	9	3
N1001J	3	1

Across the whole file, 17,863 index entries are 8,718 distinct documents. Telling a lender that four security conveyances were filed against their collateral when one was is not a rounding error.

This Actor deduplicates and reports both numbers — filingCount (real) and rawIndexEntryCount (what the FAA page displays) — so you can see the difference rather than take it on trust.

Output

One record per aircraft:

{
  "nNumber": "N100HY",
  "referenceId": "LOAN-4471",
  "status": "ok",
  "registrationFound": true,
  "registration": {
    "serialNumber": "2100",
    "manufacturer": "AVIAT AIRCRAFT INC",
    "model": "A-1B",
    "yearManufactured": "",
    "registrantName": "MORELL TIMOTHY SCOTT",
    "registrantType": "Individual",
    "city": "CIRCLE PINES", "state": "MN", "country": "US",
    "statusCode": "V", "statusDescription": "Valid registration",
    "registrationExpirationDate": "2029-08-31"
  },
  "documentIndexWindow": {
    "start": "2026-01-23", "end": "2026-07-28", "days": 186,
    "coversYourSinceDate": true
  },
  "filingCount": 2,
  "rawIndexEntryCount": 6,
  "duplicateIndexEntriesCollapsed": 4,
  "securityConveyanceCount": 1,
  "lienReleaseCount": 0,
  "ownershipEvidenceCount": 1,
  "repossessionCount": 0,
  "hasSecurityConveyanceInWindow": true,
  "hasLienReleaseInWindow": false,
  "netNewSecurityConveyancesInWindow": 1,
  "isTitleSearch": false,
  "guidance": "1 security conveyance (lien) filing(s), 1 ownership document(s) received in the window. ...",
  "filings": [
    {
      "faaDocumentId": "ARE017907387",
      "documentType": "S/A",
      "documentTypeDescription": "Security conveyance / lien",
      "category": "lien",
      "receiptDate": "2026-07-08",
      "processingDate": "2026-07-08",
      "correctionDate": "",
      "correctionType": "",
      "collateralType": "1",
      "collateralTypeDescription": "Aircraft (N-number)",
      "documentSerialId": "2100",
      "matchesRegisteredSerialNumber": true
    }
  ]
}

Document type codes are the FAA's own, decoded from the data dictionary the FAA ships inside the archive:

Code	Meaning
S/A	Security conveyance / lien
REL	Lien release
REP	Repossession
BOS	Evidence of ownership (bill of sale)
CSC	Evidence of ownership with lien
DIS	Disclaimer
CRT	Court document

Codes that appear in the file but are not in the FAA's dictionary are passed through as received and labelled, never dropped.

Input

{
  "aircraft": [
    { "referenceId": "LOAN-4471", "nNumber": "N100HY" },
    "N1001J"
  ],
  "sinceDate": "2026-06-01",
  "documentTypes": ["S/A", "REP"],
  "includeRegistration": true
}

N100HY, 100hy and N-100HY are all accepted.

How it refuses to fail silently

A lien check that quietly answers "nothing found" when the source was unreachable is worse than no tool at all, so this one fails the run instead:

1. Archive integrity — PK header, required members present, a row-count floor, and every Document Index record asserted at its documented 168 characters. The record is fixed-width and comma-delimited; parsing it as CSV silently mangles engine and propeller rows whose collateral text contains commas, so fields are cut by position from the FAA's dictionary.
2. Freshness — the newest receipt date must be within 10 days. The FAA updates this file every federal working day, so a stale mirror's silence about recent filings means nothing and the run fails rather than reporting it.
3. Window span — the receipt window must span at least 150 days, or the file is truncated.
4. Existence — every N-number is resolved against the registration master file. One that is not there comes back status: "unverified" with the reason, never as a clean zero.

An aircraft that could not be checked is reported as an error and is not charged.

Known coverage limits, stated plainly

• ~180-day window. Not a title search. See the top of this page.
• Engine and propeller liens are indexed under the component's own serial number, not the aircraft's N-number, so they do not appear under the tail number. Pass known component serials in serialNumbers to catch them.
• No lienholder names. The FAA withdrew document party names from public distribution under 49 U.S.C. §44114. They are not available from any public FAA source, bulk or web — the Actor reports this rather than leaving a blank column that looks like a bug.
• Filed is not recorded. A document in the index has been received for recordation. The index does not say whether it was recorded, rejected or later withdrawn.
• US registry only. Aircraft on foreign registries are not covered.
• Registrant street addresses are deliberately not returned. City, state and country are, which is enough to confirm you have the right aircraft.

Pricing

Pay per event, platform costs included:

• $0.05 per run — downloads and indexes the FAA archive once per run, whether you check one aircraft or two thousand.
• $0.10 per aircraft checked — aircraft the Actor could not check are not charged.

A title company charges $85 for a single aircraft title search. Different product — that one covers the full chain of title and this one covers the current window — but at $0.10 you can watch a 300-aircraft loan book every week for about $12 a month.

Source and attribution

U.S. Federal Aviation Administration, Civil Aviation Registry, Aircraft Registration Branch (AFS-750) — Releasable Aircraft Database (DOCINDEX.txt, MASTER.txt, ACFTREF.txt), https://registry.faa.gov/database/ReleasableAircraft.zip. A U.S. government work, in the public domain. This Actor is not endorsed by or affiliated with the FAA. Field layouts are taken from ardata.pdf, the FAA's own data dictionary shipped inside that archive.