AC 21-1B

Historical

Advisory circular · Production Certificates

Approved
May 10, 1976
Last reviewed
November 9, 2009
Cancelled by
AC21-43
Family
AC 21-1 · 1 version
Revision
B
14 CFR parts
21, 39
14 CFR sections
§ 21.143

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

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AC HO: 21-18 HAT OF TRANSO P BAIL: May 10, 1976

ADVISORY

STATES OF CIRCULAR

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION SUBJECI: PRODUCTION CERTIFICATES PURPOSE. This advisory circular provides information concerning Subpart & of Federal Aviation Regulations (FAR) Part 21 and sets forth acceptable means, not the sole means, of compliance with its requirements.

2. CANCELLATION. AC 21-1A dated July 9, 1971, 18 cancelled.

3. REFERENCE. FAR, Parts 21, 37, 39, 43, 45 and 183.

4. DEFINITIONS AND ABBREVIATIONS. As used herein, the following definitions and abbreviations apply:

a. Article. A material, part, component, assembly, or appliance which is used in the type certificated product, as specified in the type design data.

Supplier. Any person who furnishes services to a holder of a production certificate which affects a type certificated product, or who supplies articles for installation on a type certificated product, including articles which were not designed or manufactured by the type certificate holder. The term "Supplier" as used in this circular is synonymous with the term 'Subsidiary" as referenced in PAR 21.143.

c. Regional Office. The Engineering and Manufacturing Branch of the Federal Aviation Administration region having jurisdiction over the geographical area in which the manufacturer is located. (In the Western Region, the Aircraft Engineering Division.)

District Office. The FAA Engineering and Manufacturing District Office (EMDO) responsible for evaluation and inspection of the manufacturer's facilities. (In the Western Region, the Aircraft Engineering District Office (AEDO).)

Initiated by: AFS-180

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e. PC. Production Certificate (Ref. FAR 21, Subpart G).

f. APIS. Approved Production Inspection System (Ref. FAR 21, Subpart F).

8. PMA. Parts Manufacturer Approval (Ref. 21, Subpart K).

h. TSOA. Technical Standard Order Authorization (Ref, FAR 37).

DISCISSION. This circular covers only those sections of FAR 21, Subpart G, where further discussion, information, and examples would be helpful. The heading of each of the following main paragraphs refers to the applicable section of Subpart G.

6. FAR 21.133- ELIGIBILITY. An application for : production certificate 1s made on FAA Form 8115-12, (OMB-04-R0078) Application for Type Certificate, Production Certiticate, or Supplemental Type Certificate, which is submitted to the regional office.

7. FAR 21.135- REQUIREMENTS FOR ISSUANCE. Upon receipt of a properly executed FAi Form S110-12, and following a district office preliminary survey and evaluation of the applicant's quality control data and system, the FAA will convene a production certification board at the applicant's facilities to make the final determination for issuance of a production certificate. The applicant will be fornally advised as to the extent of his assistance needed in the production certification board activities, and of the findings and reconnendations of the district office and the production board. Where the facilities, equipment, data, procedures, and personnel of the applicant are found to meet the requirements of FAR 21, Subpart G, a production certificate wil1 be issued.

FAR 21.139-QUALITY CONTROL. A total quality control system meeting the requirements of FAR 21.139 would provide control over all phases of manufacture, including control over the manufacture of all supplierfurnished articles. The control exercised by the manufacturer over articles furnished to the manufacturer by a supplier that holds his own FAA approval (PC, APIS, PMA, ISOA) for the article may be limited to the approval of the supplier's material review systems, design changes, and to the manufacturer's usual incoming quality control procedures employed after articles are received from an outside source.

9. FAR 21.143-QUALITY CONTROL DATA REQUIREMENTS.

The data required to be submitted for approval under this regulation should be submitted to the district office at the same time the application for a production certificate is submitted to the regional office.

b. In general, the requirements of FAR 21.143 are self-explanatory and the following paragraphs provide an example of acceptable compliance:

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(1) The manufacturer's organizational structure would encure that any decisions with regard to vorkmanship, quality, conformity, safety, materials review, and corrective action are not unduly influenced by other considerations. This can be achieved by having the quality control organization report directly to top management.

(2) An effective quality control system utilizes well qualified inspectors in sufficient number to ensure that all articles, processes, procedures, and the completed products ara inspected for conformity to data, specifications, and procedures specified in the approved type design.

(3) The quality control data would be arranged in manual form, with a suitable index, and should cover each portion of FAR 21.143.

(4) When references to other company documents or data are utilized, the manual would briefly summarize the procedure, method, or system which is referenced. Any such raferenced material becomes part of the data approved by the PAA.

(5) In providing the description required by PAR 21.143(a) (3), the inclusion of, or reference to, supplementary data such as the following is considered helpful in showing acceptable compliance:

Copies of all inspection and acceptance forms and checklists for articles and completed products, together with a brief outline of instructions for their use.

(b) Imprints of the various inspection and process stamps, and their meaning.

(c) A schedule of inspection and calibration intervals for production jigs and fixtures, precision inspection tools, testing equipment, including gauges and recording equipment used in controlling processes.

(d) A listing of manufacturing processes which are relied upon to assure quality, conformity, and safety of the completed product.

c. An acceptable means of compliance with FAR 21.143(b) would be to provide in the quality control data a description of the system used to evaluate, monitor, and control all suppliers to whom the holder of a production certificate has delegated inspection duties for controlling conformity and quality, except that such a Par 9 Page 3

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description is not required for suppliers who hold an PAA approval for the article being supplied. Such a description would include an up-to-date listing, either in the manual or in a referenced company document, of all such suppliers by name, address, general nomenciature of articles or services, and any other pertinent information, such as:

Reference to the manufacturer's quality control manual by title and date.

(2) Delegation of Material Review Board (MRB) authority.

(3) Name and title of the manufacturer's or supplier's quality representative(s) who will make available purchase orders, drawings, and other applicable data.

d. Quality Control System Functions. A totally integrated quality control systen would include the following major functions;

(1) Technical Data Control.

(a) The usual practice 18 to maintain a technical data control systen which ensures that only applicable FAA - approved drawings, drawing change notices, engineering data, and quality control data are available to production and inspection personnel, and that unauthorized, inappropriate, and obsolete drawings and data are promptly removed from production areas.

(b) A drawing change control system which ensures that prior to final acceptance of products or articles, all changes to the type design are either incorporated in the applicable drawings, or described in change notices attached to such drawings.

(2) Manufacturing Processes.

governing methods for;

Selection of appropriate inspection methods and plans for articles to ensure that all characteristics affecting safety will be inspected as required, to ensure conformity to approved design data and to eliminate discrepancies from completed products and spare articies.

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(b) Ensuring that any defects which might be in a lot accepted under a statistical quality control plan will not result in an unsafe condition in an end product or spare article.

The establishing of appropriate inspection stations and the programming of inspections at each stage of production to ensure that parts, assemblies, processes, and assembly operations are inspected, and applicable tests are conducted, in accordance with data, technical materials, and procedures maintained at the station for that particular stage of production.

(d) Production planning is commonly achieved through use of fabrication and inspection instructions, shop travelers, checklists, or similar media, which not only provide control over fabrication and assembly operations, but also ensure that necessary inspections and tests will be conducted in the proper sequence, when articles and processes are in an inspectable condition. Such a system would provide for inspection and tests appropriate to all phases of the production cycle, from raw materials and related processes and services to the completed product.

Production areas would be arranged to provide segregation of manufacturing processes or operations which may adversely affect other operations; for example, separation of precision inspection from each area where grinding, cutting, sanding, or painting operations are performed.

(3) Special Processes. The integrity of processes and services utilized in the construction of articles and products is dependent upon the skill with which the work is performed, the capabilities of the equipment used, and the close control of temperatures, solutions, curing time, or other critical factors.

A system to control all processes and services, such as welding, brazing, heat treatment, plating, etc., ensures that each process is performed by trained and qualified personnel and in accordance with approved specifications containing definitive standards of quality, and that periodic inspection of gauges, solutions, or any critical equipment is controlled and documented.

(4) Inspection/Identification. Identifying articles or controlling documentation with appropriate stamps or marks traceable to the individual inspector, is a means of ensuring that only those articles and processes which have been accepted and found to conform to FAA - approved design data are used in the product.

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For example: Articles rejected &s being unusable would be conspicuously identified and subsequently controlled to preclude absolutely either their installation on the product, or their use as spare articles.

(5) Nondestructive Inspection.

(a) Operators should be qualified by the manufacturer in accordance with the manufacturer's specification.

(b) Operators' qualifications should be kept current.

(c) Inspection procedures in specifications should be approved as part of quality control date.

(d) Equipment should be inspected and calibrated periodically to assure accuracy.

(e) Realistic acceptance criteria should be established.

(f) Inspection acceptance criteria should be kept current with design data.

(8) Records should be maintained to accurately reflect that the specification requirements are constantly met.

(6) Tool and Gauge Control.

(a) Adequate manufacturing facilities, equipment, and tooling would bave the capability and reliability to ensure production of unifora duplicate articles and products conforming to the approved type design data.

(b) To preclude acceptance of nonconforming articles, or rejections due to improperly controlled tools and gauges, a quality controlsystem should incorporate a schedule for inspection and calibration, to certified national measurement standards, of all inspection tools, gauges, and testing equipment, as well as production J188, fixtures, templates, etc., which are depended upon as media for inspection. An acceptable schedule would have the inspection intervals established on the basis that such tools and gauges would be inspected prior to their becoming inaccurate, or requiring adjustment, replacement, or repair.

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(c) A recordkeeping system would ensure that each piece of equipment or container is checked prior to first usage and at the proper periodic interval, and marked to indicate the date that the next inspection 18 due, and is removed from inspection and shop areas or conspicuously identified to prohibit usage after expiration of the inspection due Supplier Control. The holder of a production certificate is primarily responsible under the requirements of PAR 21.165 for each article used in his product; therefore, he should establish a system to ensure conformity to the type design of all articles or services obtained from suppliers. Such a system would ensure

(a) Inspections and tests are extended to include supplier's inspection and tests of articles or services which cannot or will not be completely inspected upon receipt by the holder of a production certificate at his approved facilities.

(b) Provisions are made for the evaluation and/or surveillance of suppliers by the holder of a production certificate when he relies to any degree upon a supplier's quality B202 control system, or has delegated inspection duties to the supplier. Minimal source surveillance by the production certificate holder 1s customarily an acceptable means of control when the supplier provides a certification of conformance that includes reports of quality measurement data which show objective evidence that quality standards have been met.

Effective control is exercised to ensure conformity to approved design data of all articles obtained from suppliers who hold an FAA approval (PC, APIS, PMA, TSOA) for the article involved.

(d) Suppliers to the holder of a production certificate would be formally advised that their facilities' system, data, equipment, personnel, and articles being supplied are subject to evaluation and inspection by the production certificate holder and the FAA since, in effect, such supplier's facilities constitute extensions of the facilities of the holder of a production certificate.

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2 21-2B 5/10/76

(e) Articles obtained from foreign suppliers are under the same degree of control that is exercised over domestic suppliers.

In general, an undue burden may exist whenever the type certificate holder performs, or he has suppliers perform, any of his regulated functions outside the United States. Under such circumstances, the evaluation and approval ef design changes and the evaluation, approval and subsequent surveillance of manufacturers, including the supervision of designees performing outside the United States may create a burden on the FAA in administering the FARS. In accordance with FARS 21.43 and 21.137, the determination of whether or not an undue burden exists must be made by the FAA in each case. FAA surveillance of materials, parts, and appliances is not considered to be an undue burden when:

= The manufacturer completely inspects such articles for conformity and condition upon receipt in the United States, and such inspections are programmed in his FAA- approved quality control data; or An agreement is negotiated between FAA, the foreign civil air authorities and the U.S./foreign manufacturers whereby the foreig civil air authority agrees to perform inspections and surveillance on behalf of the FAA, and certifies to the FAA that each article conforms to the FAA-approved design and is in a condition for safe operation; or 3 The foreign civil air authority at the country of manufacture certifies that the article meets U.S.

requirements in accordance with FAR 21.502.

(£) An eifective purchasing and receiving inspection system precludes release to production of nonconforming or unsafe articles procured from outside sources. Such a system would ensure that:

1 Purchase orders provide specifications or other desim data in the detail necessary to ensure procurement of articles or services which meet the requirements of the approved type design.

2 All incoming articles conform to approved type design data prior to their acceptance and release to production.

Articles which are not designed or manufactured by the production certificate holder are of the same desig configuration as specified in the approved type design data.

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4 Records are maintained of all inspections and tests performed by or for the holder of a production certificate in controlling the design configuration and conformity of all supplier rurnished articles.

2 inspection/test records are utilized, as appropriate, to document, as evidence oi accomplishment, all requirec inspections, tests, rework, or rejections.

(8) Testing. The manufacturer should establish and comply with test procedures applicable to the articles or products.

(a) Test equipment should be controlled and calibrated to assure their accuracy.

Articles or products subjected to adjustment or reworked after inspection acceptance should be retested to approved test procedures.

(c) Where sampling inspection tests are utilized, other inspections and tests should be implemented as required to assure acceptance of conforming and safe products or articles.

(d) Records of all tests conducted should be maintained.

(9) Materials Review. A materials review system provides the means

(a) Control the identification, rework, and use of nonconforming articles, including the isolation and scrapping of unusable articles.

(b) Ensure the submittal of all material review actions, which result in a major nonconformity of the product or a major change in the type design data, to FAA for engineering approval prior to final acceptance or delivery of affected products or articles. The materials review system is a method acceptable to the Administration for the approval of minor changes in type design in lieu of submitting to the Administrator any substantiating or descriptive data (Ref. FAR 21.95) including manufacturing errors.

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(c) Proride fo: corrective action with regard to discrepancies in manufacturing procedures, processes, designs, or any other condition which caused the nonconforming articles, to ensure that all affected and subsequent products will be in conformity with the type design.

(d) Maintain charts or records to show the effectiveness of the corrective action program and to reveal problem areas as they arise.

(10) Storage and Issuance. A storage and issuance system would ensure:

(a) That only those articles which are identified as having passed company inspection are received into stores.

(b) Identification, segregation, and protection of articles in storage.

(c) Periodic reinspection and disposition of materials subject to deterioration from prolonged storage.

(d) Protection from damage of articles being delivered to fabrication or shipping areas or while stored in these areas prior to use.

(e) Incorporation of applicable design changes prior to release on of as for le of stored articles for installation in the product.

(11) Airworthiness Certification.

The usual practice is to record all inspections and tests required to be conducted during manufacture of the articles/ final product, and to retain those significant records attesting to the conformity and safety of the completed article/product for a period of at least two years.

(b) The effectiveness of the control exercised throughout the manufacturing cycle to ensure that quality objectives have been met is ultimately determined by the final assembly and test inspections. An acceptable quality control system would, therefore, incorporate final assembly and test procedures to ensure that:

Each completed product is subjected to a final inspection for completeness, adjustments, safety calibration, markings, placards, etc., in accordance with the applicable configuration of the approved design data for the product and model involved. Also, that each Page 10 Par 9

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product is inspected for freedom from demage, contanination, and for safe operating condition.

The means provided for leveling an aircraft are accurately installed, and that the empty weight and center of gravity of each completed aircraft are accurately determined. The holder of a production certificate may submit, for PAA consideration, a proposal based on a reliable statistical plan and evidence of product uniformity, if he desires to utilize an average empty weight and center of gravity, in lieu of weighing each aircraft.

The aircraft equipment list and, when applicable, loading charts and instructions are accurate.

(c) Functional tests of each completed product are conducted to determine whether the operating characteristics meet the approved design provisions. Examples of the type of tests generally found to be acceptable are as follows:

Each completed aircraft would be subjected to a flight test in accordance with flight test procedures and checkoff lists developed from operation characteristics and data which were found to comply with the applicable airworthiness regulations during the type test evaluation program, and approved as a part of the quality control data.

Except as noted in subparagraph d below, each completed engine would be subjected to a test run, including:

1 Break-in to determine that engine operating parameters are as specified in the type design data.

• Internal inspection is necessary to determine that the engine is in condition for safe operation. The degree of such inspection may be based on a statistical sampling plan, evidence of product uniformity, a satisfactory history of previous internal inspections, and service experience.

I Determination of test instrumentation and power/ thrust absorption devices, tolerances and correction to ensure that no production engine can be delivered with less than its type certificated rated power/ Paz 9 Page 11

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₫ Test firing of & sufficient number of rocket engines, selected from production lots in ccordance with statistical sampling plans included in the manufacturer's quality control data, which, together with the close control of materials and processes, would ensure that each engine in the lot functions properly and developed its rated thrust for the time specified in the approved type design data.

Each completed variable pitch propeller would be functionally tested to determine that it operates freely and smoothly throughout the normal range of operation, with maximum and minimum operating forces alternately applied, according to design and installation requirements.

A system to control the packing, preservation, and condition of spare articles incorporates procedures which ensure that:

Spare articles conform to applicable type design data and have not exceeded their shelf-life limits.

Prior to shipment of spare articles, all required modifications are accomplished in accordance with applicable design changes.

Spare articles are lubricated, preserved, and packed in a manner to preclude corrosion or damage in shipment, especially internal damage not readily detectable by inspection for condition upon receipt.

1 Major assemblies and components, comprising a complete aircraft, manufactured under a production certificate may be exported prior to final assembly, inspection, and flight test in accordance with FAR 21.325(b), providing the holder of the production certificate has established FAA-approved assembly and flight test procedures; and the extent of disassembly is the same as an aircraft which has been disassembled for shipment purposes.

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