FAA aircraft compliance checklist under 14 CFR Part 21

An FAA compliance checklist is the table that lists every section, paragraph and sub-paragraph of the certification basis at its amendment level, states whether and how the applicant will show compliance with each, and points to the compliance report that carries the evidence. FAA Order 8110.4C names it in paragraph 2-3d as the way an applicant ensures that all showings have been made, and expects it in the certification plan that every type certificate applicant must submit and keep current. Part 21 does not prescribe its columns. This guide sets out what 14 CFR Part 21 and the order require of it, the columns that keep it usable through the project, seven steps to build one, and which of those steps an AI teammate can draft. It is the FAA companion to the guide on the certification-basis compliance matrix, which covers EASA Part 21 alongside the FAA.

What Part 21 and Order 8110.4C require

The rule is short. Under 14 CFR 21.17(a) an applicant for a type certificate must show that the product meets the requirements of the subchapter effective on the date of application, unless the FAA specifies otherwise or compliance with a later amendment is elected or required, plus any special conditions the FAA prescribes. Under 21.20 the applicant must show compliance with all applicable requirements, provide the FAA the means by which such compliance has been shown, and provide a statement certifying that it has complied. Under 21.21(b) the applicant submits the type design, test reports and computations necessary to show that the product meets the applicable requirements. The checklist is where those three obligations meet: one row per requirement, the means in a column, the report in another.

The order turns the rule into a document. Paragraph 2-3d requires all type certificate applicants to submit a certification plan and to keep it current throughout the project, and lists what it must contain before the implementation phase. Paragraph 2-4j describes the certification basis the FAA establishes and the applicant agrees to, identifying the specific parts and amendment levels with which the applicant must show compliance. Paragraph 2-6m explains what a compliance report has to do: present the evidence that supports the claim that the type design meets a particular requirement of the certification basis, in a logical order from the requirement to the claim.

What the certification plan must contain

Paragraph 2-3d of the order lists eleven items. For a simple project the FAA expects the complete plan with the application; for a complex one it expects as much as is known and the rest as it becomes known, but the plan must be complete before the implementation phase. The checklist is item 6, and it depends on items 2 to 5 being settled first.

1. General information: applicant, application date, model designation.
2. A description of the proposed design or design change, with sketches and schematics.
3. The intended regulatory operating environment, for example parts 91, 121 or 137, the kinds of operation and the kind of maintenance programme.
4. The proposed certification basis: regulation paragraphs and sub-paragraphs with amendment levels, exemptions, ELOS findings and special conditions.
5. A description of how compliance will be shown: ground test, flight test, analysis, similarity or other acceptable means, in enough detail to determine that all necessary FAA data will be collected and all findings can be made.
6. A list of the documentation that will be submitted and how the applicant will ensure that all showings have been made, which the order says can be done with a compliance checklist addressing each applicable section.
7. A list of test articles, with any features that need special instructions to the manufacturing inspector.
8. How continued operational safety requirements will be met after the certificate is issued.
9. A project schedule with the major milestones.
10. The designated engineering representatives to be used, their areas of authority, and whether they approve or recommend approval of data.
11. All other FAA delegation activity to be used, with function codes and proposed inspection activities.

The certification basis: what goes in the header

Every row of the checklist traces to one requirement of the certification basis, so the basis has to be written down before the first row. Under 21.17(a)(1) the date of application fixes the amendment level; under 21.17(c) the application is effective for five years for a transport category aircraft and three years for any other type certificate, and under 21.17(d) an application that runs past that period is refiled or extended with a new effective date for the requirements. If the applicant elects to comply with an amendment that took effect after the application, 21.17(e) requires it to comply with any other amendment the FAA finds directly related, and paragraph 2-4j(3)(g) of the order asks for that election to be documented in the certification plan and the certification basis.

The basis then carries the adjustments: special conditions prescribed under 21.16 for a novel or unusual design feature, equivalent level of safety findings, and exemptions. Paragraph 2-4j of the order lists all three, and each needs its own rows. For special classes of aircraft with no airworthiness standards of their own, 21.17(b) makes the basis the portions of parts 23, 25, 27, 29, 31, 33 and 35 the FAA finds appropriate, or airworthiness criteria that provide an equivalent level of safety; the header then names the criteria document rather than a part.

The means of compliance the FAA recognises

The FAA does not code its means of compliance. Paragraph 2-3d(5) of the order names ground test, flight test, analysis, similarity or other acceptable means, and paragraph 2-6m lists the kinds of evidence a compliance report draws on: FAA publications, certification testing, analysis, engineering examinations, similarity, software design assurance, and any other data the FAA deems acceptable. An organisation that also certifies with EASA can keep a single table by adding a column for the EASA code from Appendix A to AMC 21.A.15(b). The pairing below is a working convention, not a rule from either authority.

The columns of a checklist that survives to the certificate

A checklist that satisfies the application is rebuilt several times before the type certificate. One that is built as the register the project runs from carries these columns from the first issue.

• Requirement reference, with the amendment level in the header and each special condition and ELOS finding numbered in the same series.
• Requirement summary, a few words, so the row can be read without opening the part.
• Applicability, as applicable, not applicable or partial, and the rationale in a separate column.
• Means of compliance, in the order's vocabulary, with the advisory circular followed where there is one.
• Compliance report, by number and issue, one column per report if a row needs more than one.
• Test article and conformity, for rows that need test data.
• Delegation, whether a DER or an ODA unit member will approve or recommend approval of the data, as paragraph 2-3d(10) and (11) ask.
• Owner and status, with a column for certification team comments and the issue paper number when one is open.

Seven steps to build the checklist

1. Fix the certification basis and put it in the header. Record the date of application, because under 14 CFR 21.17(a)(1) it sets the amendment level of every airworthiness standard the product must meet. List the applicable parts and amendments, the special conditions under 21.16, the equivalent level of safety findings, the exemptions, and any later amendment you have elected together with the amendments the FAA finds directly related under 21.17(e). Order 8110.4C paragraph 2-4j describes the certification basis the FAA establishes and the applicant agrees to; the checklist header must say the same thing.
2. Enumerate every section, paragraph and sub-paragraph. Paragraph 2-3d(4) of the order asks for the certification basis "including applicable regulation paragraphs and subparagraphs with amendment levels". Make one row per sub-paragraph at the frozen amendment, and one row per special condition and ELOS finding. Section headings are not rows. This step is mechanical, which is why it is the first thing worth automating and the place where a hand-built checklist loses rows without anyone noticing.
3. Decide applicability and write the rationale. Mark each row as applicable, not applicable or partially applicable against the design description and the intended regulatory operating environment that 2-3d(3) asks you to state. Every "not applicable" carries a one-sentence reason: the configuration is not present, the kind of operation is not requested, the paragraph addresses another class of product. The certification team reads the rationale before it reads anything else.
4. Assign the means of compliance to each row. Paragraph 2-3d(5) names ground test, flight test, analysis, similarity or another acceptable means, and asks that the description be sufficient to determine that all necessary FAA data will be collected and all findings can be made. Where an advisory circular describes a common means, name it in the row; paragraph 2-5d notes that the detail needed to avoid ambiguity decreases when common means described in ACs are chosen.
5. Name the compliance report and plan the data behind it. Paragraph 2-3d(6) asks for the list of documentation that will be submitted and how the applicant will ensure all showings have been made. Give each row the number and issue of the compliance report that will carry the evidence. For rows that need test data, list the test article under 2-3d(7) and plan the conformity inspections that 21.33 requires before an article is presented for FAA test, and the prerequisites that 21.35(a) sets before flight testing begins.
6. Run the project from the checklist, not beside it. Add a status per row, an owner, and a column for the certification team's comments and open issue papers under paragraph 2-4g. The order requires the certification plan to be kept current throughout the project, and the completed plan under 2-5d is what the certification team uses to satisfy itself that, if executed, the plan would show compliance. A checklist that is only updated for TCB meetings is not the document the project runs from.
7. Close every row before the statement of compliance. Under 21.20 the applicant must show compliance with all applicable requirements, provide the FAA the means by which compliance has been shown, and provide a statement certifying compliance. Paragraph 2-6m adds that, unless a data retention agreement preserves FAA access, the deliverables necessary to show compliance must be documented in the statement and submitted. A row without a compliance report is an open item, and the statement cannot be signed over open items.

Amended type certificates and STCs

A change to a certificated product has its own checklist, scoped by 14 CFR 21.101. Under 21.101(a) the applicant shows that the change and the areas affected by the change comply with the requirements in effect on the date of application for the change. Under 21.101(b) the applicant may show compliance with an earlier amendment for a change the FAA finds not significant, for areas not affected by the change, and for affected areas where compliance with the current amendment would not contribute materially to the level of safety or would be impractical, provided the earlier amendment is not older than the one in the type certificate. Under 21.101(d) a novel or unusual design feature in the change brings special conditions under 21.16. The checklist for a change therefore carries a column that records, for each row, which amendment applies and under which paragraph of 21.101.

Whether the change needs a checklist at all follows from 21.93(a): a minor change has no appreciable effect on weight, balance, structural strength, reliability, operational characteristics or other characteristics affecting airworthiness, and may be approved under 21.95 by a method acceptable to the FAA; everything else is a major change, and under 21.97(a) its applicant provides substantiating data, shows that the change and affected areas comply, provides the means, and certifies compliance, the same three obligations as 21.20. A supplemental type certificate under 21.113 and 21.115 rests on the same showing. When the change is so extensive that a substantially complete investigation of compliance is required, 21.19 calls for a new type certificate, and the checklist starts again from the whole part.

What AI can draft and what the applicant decides

Most of the checklist is derivation from two controlled inputs: the part at its frozen amendment and the design description. That is work a language model does well, provided it works only from those documents and cites the paragraph behind every proposal. The rest is judgement, and under 21.20 the judgement is the applicant's.

The conditions that make this safe are the ones set out in Can AI be trusted for aviation compliance documentation?: a controlled corpus that holds the parts at the right amendment and nothing else, citations at paragraph level on every proposed row, a boundary that stops users from altering that corpus, and a review that leaves a record of who accepted each row. The text of 21.20 and 21.17(a), quoted verbatim, is on the rule point page.

Six mistakes that produce findings

• Rows built against the current eCFR instead of the certification basis. The part was amended after the date of application, and the rows quote text that is not in the basis. Freeze the amendment level first and check the rows against it, not against the latest text.
• An elected later amendment without its directly related amendments. 21.17(e) makes them part of the basis, and paragraph 2-4j(3)(g) of the order expects the election to be recorded in the plan.
• "Not applicable" without a rationale. The certification team cannot accept a decision it cannot read.
• A means of compliance with no report number. A means is a promise. Rows that say "analysis" with no substantiation report are open items, not compliance.
• The previous project's checklist, renamed. Applicability was decided for another design and another operating environment. Reuse the structure, redo the decisions.
• A checklist that stops moving after the application. The order requires the plan to be kept current, and design changes reopen rows. If the checklist does not move with the design, the statement under 21.20(b) rests on a document that no longer describes the product.

How Wingman360 Teammate builds one

The compliance-matrix workflow in Wingman360 Teammate starts from the parts and amendments that the organisation's administrators have ingested for the certification basis, together with the special conditions, the design description and the intended operating environment. It enumerates the requirements to sub-paragraph level, proposes applicability and a means of compliance for each row with a citation into the source, and produces the checklist in the columns above for engineering review. Engineers accept, edit or reject every proposed row, and the statement of compliance is written and certified by the applicant. The same approved knowledge base answers questions during the project, so the checklist and the answers share one controlled source. Each deployment is a dedicated single-tenant instance in the customer's own cloud or on-premise, with a local model option so that no design data leaves the network. The design and production organisations page lists what else it drafts for a Part 21 programme.