Advisory U.S. Department of Transportation Circular Federal Aviation Administration Subject: GUIDE FOR OBTAINING A Date: 09/27/07 AC No: 21-40A SUPPLEMENTAL TYPE CERTIFICATE Initiated by: AIR-110 This advisory circular (AC) is intended as a certification guide for obtaining a supplemental type certificate (STC). This AC both consolidates existing policy documents, and certain ACs that cover specific paragraphs of the regulations, into a single document and adds new guidance.
This AC is not mandatory and does not constitute a regulation. It is issued for guidance purposes and to outline a method of compliance with the rules. A person may elect to follow an alternative method, provided the FAA finds it to be an acceptable means of complying with the applicable requirements of Title 14 CFR.
/s/ Susan J. M. Cabler Associate Manager, Aircraft Engineering Division AIR-100
TABLE OF CONTENTS Paragraph Page
CHAPTER 1. INTRODUCTION1
1-1. Purpose1
1-2. References1
1-3. Cancellation1
1-4. Request For Information1
1-5. Regulatory Foundation1
1-6. Key Facts about Supplemental Type Certificates (STC)2
1-7. Key Steps in the STC Process3
1-8. Operation and Maintenance of a Product Modified By an STC5
1-9 . Undue Burden on the FAA5
1-10. STC Project Management6
1-11. FAA Project Team6
1-12. FAA Project Classification And Oversight8
1-13. U.S. STCs Using Foreign-Registered Test Aircraft8
CHAPTER 2. THE STC PROCESS9
2-1. General9
2-2. Phase I, Conceptual Design9
2-3. Process Orientation9
2-4. Pre-Project Guidance9
2-5. Familiarization Briefing10
2-6. Certification Plan Requirement10
2-7. Phase II. Requirements Definition10
2-8. Applying For STC and Submitting the Certification Plan10
2-9. FAA Establishing a Project12
2-10. When applicable, submit a Project Specific Certification Plan (PSCP)13
2-11. Establishing the Certification Basis13
2-12. Phase III. Compliance Planning13
2-13. FAA Involvement14
2-14. Using Parts Produced by Technical Standards Order (TSO) Authorization or Parts
Manufacturer Approval (PMA) in Certification Testing15
2-15. Completed [Project Sp ecific] Certification Plan15
2-16. Interim Type Certification Board (TCB) Meeting For
(Project Specific) Certification Plan Agreement15
2-17. Phase IV. Implementation16
2-18. Data Submittal For Approval17
2-19. FAA Design Evaluation17
2-20. Conformity Inspections18
2-21. Applicant Test Plan and FAA Approval19
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2-22. (Before Witnessing) E ngineering and Flight Tests19
2-23. Engineering Ce rtification Tests19
2-24. Engineering Compliance Inspection20
2-25. Analysis21
2-26. Experimental Airworthiness Certificate21
2-27. Ground Inspections, Ground Tests, and Flight Tests21
2-28. Review of Applicant’s Flight Test Results21
2-29. Type Inspection Authorization (TIA)22
2-30. Flight Test Conformity Inspecti ons and Certification Flight Tests22
2-31. Aircraft Evaluation Group (AEG) Activities23
2-32. Aircraft Flight Manual Supplement24
2-33. Supplemental Type Certificate Issued25
2-34. Phase V. Post Ce rtification Activities25
2-35. Aeronautical Pr oduct Enters Service26
2-36. Continued Operational Safety26
2-37. Changes to Instructions for Continued Airworthiness (ICA)26
2-38. Changes and Deviations26
2-39. Data Retention27
2-40. Required Documents27
CHAPTER 3. APPLI CABLE REGULATIONS41
3-1. General41
3-2. Certification Basis41
3-3. Availability of Regulations41
CHAPTER 4. USE OF DESIGNEES44
4-1. General44
4-2. Designated Engineering Representatives (DERs)44
4-3. Designated Manufacturing Inspection Representatives (DMIRs)45
4-4. Designated Airworthiness Representatives (DARs) and
Organizational Designated Airworthiness Representatives (ODARs)46
4-5. Responsibilities of the Applicant46
CHAPTER 5. DATA47
5-1. Required Data47
5-2. Descriptive Data47
5-3. Substantiating/ Compliance Data50
5-4. Drawing Package52
5-5. Drawing Revision Levels52
5-6. Good Drawing Practices52
5-7. Tolerances52
5-8. Drawing List52
5-9. Examples52
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5-10. Guidelines For Checking Drawings53
CHAPTER 6. INSPECTIONS57
6-1. General57
6-2. Conformity Inspections57
6-3. Compliance Inspections57
6-4. Parts Manufacturer Approval (PMA) and Production Inspections57
CHAPTER 7. TYPE INSPECTION AUTHORIZATION59
7-1. General59
7-2. FAA Form 8110-1, Type Inspection Authorization59
7-3. TIA Description59
7-4. TIA Section 18, Part I59
7-5. TIA Section 18, Part II59
7-6. TIA Section 18, Part III59
7-7. Supplemental Type Inspection Report (STIR)59
CHAPTER 8. TESTS61
8-1. General61
8-2. Component Tests61
8-3. Ground Tests61
8-4. Flight Tests61
8-5. Simulator Tests63
CHAPTER 9. ADMINIS TRATIVE ACTIONS64
9-1. Cancellation of a Project64
9-2. Issuance of an STC64
9-3. Re-Issuance of an STC65
9-4. Transferring Ownership of an STC64
9-5. Use of an Available STC64
9-6. Amendments to an STC65
9-7. Duration of an STC65
9-8. Loss of an STC65
CHAPTER 10. SPECIAL CONSIDERATIONS FOR U.S. STCs USING FOREIGN-
REGISTERED TEST AIRCRAFT66
10 - 1. General66
10 - 2. Special Considerations for an Applicant Using a Foreign-
Registered Test Aircraft66
10 - 3. Special Considerations for the F AA Aircraft Certification Office (ACO)67
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APPENDIX 1. FAA FORM 8110-12, APPLICATION FOR TYPE CERTIFICATE,
PRODUCTION CERTIFICATE, OR
SUPPLEMENTAL TYPE CERTIFICATEA-1
APPENDIX 2. SAMPLE DRAWING PACKAGEA-5
APPENDIX 3. SAMPLE SUPPLEMENTAL TYPE CERTIFICATEA-8
APPENDIX 4. GUIDE FOR PREPARING FAA FORM 8120-10, REQUEST FOR
CONFORMITYA-11
APPENDIX 5. EXAMPLE STC CHECKLISTA-15
APPENDIX 6. LIST OF FAA FORMSA-17
APPENDIX 7. LIST OF FAA AIRCRAFTA-18
APPENDIX 8. GLOSSARY OF TERMSA-20
LIST OF FIGURES Figure Page
Figure 2-1. STC Process28
Figure 2-2. TC, ATC and STC Process30
Figure 2-3. STC Project Initiation Checklist32
Figure 2-4. Sample Certification Plan34
Figure 2-5. Sample Applicant Compliance Checklist Format36
Figure 2-5.A. First Page of the Compliance Checklist39
Figure 2-5.B. Second Page of the Compliance Checklist40
Figure 3-1. Regulations Mo st Commonly Used for STC Applications42
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CHAPTER 1. INTRODUCTION
1-1. Purpose.
a. This advisory circular (AC) is a certification guide for obtaining a supplemental type certificate (STC). It is intended for civilian applicants only. We have written it to help designers, manufacturers and installers applying for STCs to better understand the STC process. The guid ance in this AC is general in nature and intended to help an applicant gain a basic understanding of the STC process and our respective roles and responsibilities.
b. This AC is not mandatory and does not constitute a regulation. This AC describes an acceptable means, but is not the only means, to gain certification. The primary source of information for certification contained in this AC is derived from Order 8110.4, Type Certification. You’ll find the most current version of this order on the internet at http://rgl.faa.gov.
1-2. References. Title 14 of the Code of Federal Regulatio ns (14 CFR) parts 21, 23, 25, 27, 29, 31, 33, 34, 35, 36, 39, 43, 45, 91, 121, 135, 183, and predecessor regulations.
1-3. Cancellation. AC 21-40, Ap plication Guide for Obtaining a Supplemental Type Certificate, dated May 6, 1998 is canceled.
1-4. Request for Information. If you have questions, o r need more information about this AC, contact the FAA Certification Procedures Branch, (AIR-110) at 800 Independence Avenue SW, Washington DC 20591. Telephone (202) 267-1575.
1-5. Regulatory Foundation.
a. Title 49 of the United States Code (49 U.S.C.), section 44701, requires the Federal Aviation Adm inistration (FAA) to promote safe flight of civil aircraft in air commerce. We do this by prescribing minimum standards for the design, material, construction, quality of work, and performance of aircraft, aircraft engines, propellers, and appliances. Title 14 of the Code of Federal Regulations (14 CFR) prescribes airworthiness standards which are FAA minimum safety standards.
b. When we find that a product (an aircraft, aircraft engine, or propeller), is properly designed and manufactured, performs properly, and meets the prescribed airworthiness standards, we issue a design approval in the form of a type certificate. When a typecertificated product is altered, we must evaluate the changed product. After finding that the changed product complies with the prescribed airworthiness standards, we will issue an STC or, in the case of type certificate holders, either an amended type certificate (ATC) or an STC (at type certificate holders’ discretion). Refer to 14 CFR § 21.113.
c. Any individual or company may apply to change a type-certificated aircraft, aircraft engine, or propeller.
d. A type design change is classified as minor or major (see 14 CFR § 21.93). A minor change has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product.
Minor changes to type design may be approved under a method acceptable to the Administrator before the type certificate (TC) or the STC holder submits any substantiating or descriptive data (14 CFR § 21.95). All other changes are major changes. In addition to being classified as minor or major change, and to comply with 14 CFR part 36, a type design change may be classified as an acoustical change.
e. A major change to type design normally requires us to issue a STC or, in the case of the type certificate holder, an ATC. But, the holder of the TC for the product may elect to apply for an STC instead of an ATC (14 CFR § 21.113). However, if we find that the proposed change is so extensive that it will require a substantially complete investigation of compliance with the applicable regulations, then the applicant will have to apply for a new type certificate.
f. Applicants make the initial determination of major versus minor change in type design based on 14 CFR § 21.93. However, minor design changes may be considered major alterations and can be approved through your local flight standards district office (FSDO).
Your aircraft certification office (ACO) or FSDO will help you by referencing FAA Order 8300.10, Airworthiness Inspector’s Handbook, Vol. 2, Chapter 1, Perform Field Approval of Major Repairs and Major Alterations. The Handbook offers a decision flow chart for the field approval process, plus a major alteration job aid showing specific examples of when we will require a proposed modification to be approved as an STC.
1-6. Key Facts about Supplemental Type Certificates (STC).
a. An STC is the FAA’s approval of a major change in the type design of a previously type certificated product. An FAA ACO issues an STC. An STC may also be issued by an organization representative of the FAA; as an example, a designated alteration station (DAS) or an organization designation authorization (ODA) with STC privileges (STC - ODA). A DAS or STC - ODA follows the procedures in their FAA approved procedures manual when accomplishing STC projects.
b. An STC is classified as either “one-only” or “multiple.”
(1) We issue “one-only” STCs for modification of a specific serial numbered aircraft, aircraft engine, or propeller. (The design and substantiating data may be of a quality that prevents parts from being reproduced, or the applicant only wants one.) This type of STC cannot be amended.
(2) We issue “multiple” STCs when the applicant intends to modify two or more aircraft, aircraft engines, or propellers. Th e design and substantiating data must be of a quality that enables parts and the installation to be reproduced.
(3) A list of all “multiple” STCs for each product model is available on the internet in the FAA Regulatory and Guidance Library at http://rgl.faa.gov. You can search this online database to determine if another STC has been issued that would satisfy your intended requirement.
c. We award certain privileges when issuing an STC. The STC holder may:
(1) (In the case of aircraft) obtain airworthiness certificates for specified aircraft modified in accordance with the STC; and
(2) Obtain a production approval for the change in type design approved by that STC. (This privilege applies only to an STC classified as a “multiple” STC.)
(3) Install, or sell for installation, the modification defined by the STC.
d. You are responsible for the design and quality of all parts associated with the STC approval.
1-7. Key Steps in the STC Process.
a. Applicants should discuss the design (preferably during early design) with your local FAA certification office so that both the FAA and you can establish that the proposed modification is feasible for approval. If possible, have this discussion before modifying the product.
b. If you apply for an STC, submit FAA Form 8110-12, Application for Type Certificate, Production Certificate, or Supplemental Type Certificate, to the FAA certification office serving your geographic area. The website, http://www.faa.gov/aircraft/air_cert/locate_office/aco/, lists the addresses, telephone numbers, and geographic areas of service for all FAA certification offices. Be advised that your STC application may be subjected to a project sequencing process which may result in a delay of the initiation of your project or it may be assigned to another ACO. For further information regarding the sequencing process contact your local ACO.
c. You will find the complete set of certification requirements in 14 CFR or the predecessor, Civil Air Regulations (CAR). The type certificate data sheet (TCDS) for the unmodified product lists specific certification requirements, including regulatory airworthiness requirements, special conditions, findings of equivalent level of safety, and exemptions to the regulatory requirements. The certification requirements for your STC project will include those requirements in the TCDS for the unmodified product, and may include later regulatory requirements for areas affected by the proposed design change. FAA 3
AC 21.101-1, Establishing the Certification Basis of Changed Aeronautical Products, covers how to establish a certification basis for changed products in detail. You’ll find the most current version of this AC on the internet at http://rgl.faa.gov.
d. You are responsible for showing that the changed product complies with the applicable regulations. You do this by submitting substantiating data, such as computations and analyses, and results of tests, including flight tests, that demonstrate the modified aircraft, aircraft engine, or propeller complies with the applicable regulations.
e. Your data submittals must contain enough detail and substantiating data to completely describe the design of the modification or installation, and to demonstrate that the design complies with the applicable airworthiness standards.
f. You must conduct all of the conformity inspections and determine whether the modification conforms to the descriptive data. The FAA manufacturing inspector verifies that your conformity is accurate and complete and that you comply with 14 CFR § 21.33(b). Our compliance inspection verifies that the modification meets the applicable airworthiness standards.
g. Testing is required to demonstrate compliance with the applicable regulations. Test results from, but not limited to, component, ground, and flight testing, may be required.
Component testing demonstrates that detail parts, components, or subassemblies function as required to meet the applicable airworthiness standards. Ground and flight testing demonstrate that the completed modification or installation complies with the applicable airworthiness standards.
h. How long it takes to obtain FAA approval of a proposed change in type design varies with the complexity of your project. Plan, coordinate and schedule inspections, meetings, tests, and other events well in advance to ensure appropriate FAA personnel are available. Schedule and coordinate inspections, meetings, tests and other events during the planning phase of your project to the greatest extent possible. Present each schedule change, along with its impact on the overall project, to us as soon as possible for discussion and concurrence.
i. We encourage your use of designees authorized by us to approve data, conduct inspections, and witness tests. Chapter 4 describes the use of designees in detail.
j. Issuance of an STC is the primary goal of the STC certification process. However, it’s not the end of the process. There are post-issuance activities, such as:
(1) Changing or updating the design data,
(2) Maintaining the production approval,
(3) Maintaining the certification data, the method of approving minor changes, and 4
(4) Implementing the plan for continued airworthiness.
k. Discuss a post-STC plan with us. It’s particularly important that you have a plan for evaluating service data, notifying us of safety critical service problems, and expediting development of corrective actions for unsafe conditions. Another important element of the plan is the process by which you modify the changed product and we amend the STC.
l. Major changes to the original STC must be FAA-approved before you operate the changed product. Minor changes may be accomplished in a manner found acceptable to the FAA. Submit both types of changes to the original STC design and any substantiating data for approval and inclusion in FAA data files.
1-8. Operation and Maintenance of a Product Modified by an STC.
a. In addition to approving the data for the STC, we also review how the alteration will affect aircraft operation and maintenance after the STC is complete. As required, include an aircraft flight manual supplement (AFMS), placards, instructions for continued airworthiness (ICA), installation and removal instructions, and other necessary information in the STC installation package. You must give the owner or operator the information needed to keep the aircraft safe and airworthy.
b. Develop ICA and present it in conjunction with the STC process. The ICA contains an airworthiness and maintenance portion. We do approve the airworthiness limitation section of the ICA. On the other hand we don’t approve the maintenance portion of the ICA, but we accept it, per the requirements in 14 CFR §§ 23.1529, 25.1529, 27.1529, 29.1529,
31.82, 33.4, and 35.4. ICA instructs how to maintain products that are altered, and appliances that are installed, in accordance with an STC. If there is a need for you to obtain a design approval without a complete ICA, we will do so if we approve a plan submitted by you that ensures all ICA requirements will be complete and accepted before the first affected aircraft is operated with a standard airworthiness certificate. This means an aircraft can be modified, but cannot return to service until we accept the complete ICA. In this case we must include a statement saying, “Instructions for Continued Airworthiness are Incomplete”.
The aircraft will be eligible to return to service with a standard certificate of airworthiness when the ICA are complete and accepted in the Limitations section of the STC. FAA Order 8110.54, Instructions for Continued Airworthiness Responsibilities, Requirements, and Contents, tells ACOs how to help applicants write ICA.
c. ICA must include all necessary functions to keep the aircraft airworthy. Include information such as troubleshooting, servicing, inspections, and functional checks.
d. An aircraft alteration that changes the operating characteristics or procedures for safe operation should include an aircraft flight manual supplement (AFMS). See chapter 2 of this AC for more details about AFMS.
1-9 . Undue Burden on the FAA. Title 14 CFR §§ 21.43, 21.137, 21.303(g), and
21.601(c), state that the Administrator does not issue type certificates and production 5
approvals when the manufacturing facilities are located outside the United States, unless the Administrator finds that the location of the manufacturer's facilities places no undue burden on the FAA.
1-10. STC Project Management. Effective management by both you and us is essential to successful completion of an STC certification project. In addition to this AC, we and the aviation industry jointly developed the FAA and Industry Guide to Product Certification (“the CPI Guide”) to help you lay a foundation from which to build mutual trust, leadership, teamwork, and efficient business practices. The processes and products described in the CPI Guide enable both you and us to fulfill our respective roles and expedite the certification process while still focusing on significant safety issues. The Guide is available on the internet at: http://www.faa.gov/aircraft/air_cert/design_approvals/media/CPI_guide_II.pdf.
a. The CPI Guide describes how to plan, manage and document an effective, efficient product certification process. It desc ribes the working relationship between us and the applicant. Although focused on large or complex projects, the Guide’s principles of upfront planning, project management, and documenting the certification process and working relationship are applicable to all applicants and all projects, large or small.
b. Use of the Guide’s principles enables planning and mutual commitment between the FAA and an applicant. Both parties should agree on what certification activities each will accomplish and how the activities will be conducted. Both parties establish a certification plan. Employing the guidance provided in this Advisory Circular will help to efficiently plan the certification project. It will enable both the FAA and the applicant to agree upon the expectations and certification activities for which each will be responsible.
Chapter 2 will discuss each phase of managing a certification project in more detail. See the Guide for a complete description of the six-phase approach to managing a certification project.
1-11. FAA Project Team.
a. The FAA certification project team is the working level group at the ACO that works with you, conducts the certification project, and makes the findings of compliance.
We will assign a project manager and establish a certification project team for each STC project. A generic project team normally consists of the following:
(1) A project manager, project,
(2) Engineers or technical specialists in each required discipline based on the
(3) Flight test pilots and flight test engineers,
(4) Manufacturing inspectors, 6
(5) Operations inspectors and airworthiness inspectors from the aircraft evaluation group (AEG), and
(6) A project officer and other persons at the discretion of the accountable directorate.
b. We establish a team for a specific project based on the project’s complexity and the number of technical disciplines involved. The team may include some or all of the staff listed above. Once the project team is established, we transmit the team’s composition, by name and discipline, to you.
c. The project manager is the ACO representative responsible for planning, reviewing, evaluating, and coordinating all aspects of a certification project. The project manager organizes the project team and is our official point of contact with you. The project manager will notify the ACO manager (or the ACO manager's issuing representative) to issue the STC once they are satisfied that all applicable airworthiness standards and other requirements (such as noise standards and fuel venting requirements) have been met and that you have established a satisfactory post certification activity plan. While you should send all formal correspondence to the FAA project manager, you can discuss technical issues directly with the applicable technical specialists and inspectors on the project team.
d. The project officer is the person in the accountable directorate designated to monitor the project. The project officer will provide project-specific rules and policy to the project team and is the focal point with the directorate for policy. The project officer is also responsible for standardization of similar projects across the ACOs. For a well-planned and executed project, it’s important to involve the project officer early to identify issues, rules and policy documents of critical concern to the directorate.
e. We draw engineers or technical specialists from three basic disciplines: airframe, systems and equipment, and propulsion. Airframe engineers cover the structural aspects of certification. Propulsion engineers cover engines, engine installations, fuel systems, auxiliary powerplant systems, and aircraft noise. Systems and equipment engineers normally cover electrical, avionics, and mechanical systems.
f. FAA flight test pilots and flight test engineers cover aircraft flight characteristics and performance issues. Flight test pilots are primarily responsible for aircraft flying qualities and human factor evaluations, while flight test engineers are primarily responsible for aircraft performance and aircraft flight manuals.
g. FAA manufacturing inspectors conduct conformity inspections of detail parts during fabrication, test instrumentation and test setups. They also conduct installation conformity inspections on flight test aircraft to determine aircraft airworthiness before official flight testing. For multiple STCs, our installation conformity inspection includes evaluating process controls to ensure that after we issue the STC, production of uniform and consistent installations or modifications continues.