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CHAPTER 4. PRODUCTION APPROVALS
4-1. GENERAL 39
4-2. MANUFACTURING LIMITATIONS RELATED TO A BILATERAL AGREEMENT 39
4-3. EXTENSIONS OF FAA PRODUCTION APPROVALS TO COUNTRIES OUTSIDE THE U.S. 39
4-4. PRODUCTION UNDER LICENSE TO A U.S. APPROVAL HOLDER 40
4-5. CAA SURVEILLANCE ASSISTANCE ON BEHALF OF THE FAA 40
CHAPTER 5. CONTINUED AIRWORTHINESS
5-1. GENERAL 41
5-2. CONTINUED AIRWORTHINESS DOCUMENTS 41
5-3. NOTIFICATION OF UNSAFE CONDITION AND MANDATORY CONTINUING AIRWORTHINESS ACTIONS 42
5-4. DESIGN CHANGES 43
5-5. APPROVAL OF DESIGN DATA USED TO SUPPORT REPAIRS 43
APPENDIX 1. AIRCRAFT CERTIFICATION SERVICE ORGANIZATIONAL CHART (1 page)
APPENDIX 2. ACCOUNTABLE FAA DIRECTORATES (2 pages)
APPENDIX 3. BILATERAL AGREEMENTS RELATED TO AIRWORTHINESS (4 pages)
APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT UNDER BILATERAL AGREEMENTS (6 pages) x
CHAPTER 1. INTRODUCTION
1-1. GENERAL. Aircraft airworthiness certification in the U.S. is a public safety function performed by the FAA with the purpose of ensuring the safety and environmental acceptability of U.S.-registered civil aircraft operating in air commerce. A U.S. statute--49, U.S.C. 106(g)--sets forth the duties and powers of the FAA Administrator in the safety regulation of civil aeronautics, including airworthiness certification of civil aeronautical products.
a. Title 49 U.S.C. 44701(a) charges the FAA Administrator with prescribing and revising minimum standards required in the interest of safety for appliances and for the design, material, construction, quality of work, and performance of aircraft, aircraft engines, and propellers. The U.S. airworthiness standards set forth by the FAA within 14 CFR, subchapter C are promulgated to implement this statute.
b. Title 49 U.S.C. 44711(a)(1) makes it unlawful for any person to operate in air commerce any U.S. registered civil aircraft for which there is not an airworthiness certificate currently in effect, or in violation of the terms of that airworthiness certificate.
c. Title 49 U.S.C. 44704 specifies and defines the FAA Administrator’s role in establishing requirements and issuing Type Certificates, Supplemental Type Certificates, Production Certificates, and Airworthiness Certificates. Additional information about these certificates can be found in Chapters 2, 3, and 4 of this Advisory Circular (AC).
1-2. AIRCRAFT CERTIFICATION SERVICE’S INTERNATIONAL VISION AND MISSION The Aircraft Certification Service’s International Vision is that of a global network of airworthiness authorities working cooperatively to promote the highest level of public confidence in the safety of the international air transportation system with the lowest practicable regulatory burden to that system. Its mission is working in partnership with the global aviation community to continuously improve the safety of the international air transportation system and achieve international harmonization of aircraft certification standards, practices, and procedures. Bilateral agreements facilitate cooperation between the FAA and its partner aviation authorities, and minimize duplicative certification activities related to the import and export of aeronautical products.
1-3. FAA AIRCRAFT CERTIFICATION SERVICE ORGANIZATION
a. The FAA Aircraft Certification Service organizational structure is shown in appendix 1.
b. Four Aircraft Certification Directorates have been established to develop and ensure standard application of technical policies in the type certification of particular 1
kinds of products. These directorates and assigned product responsibilities are as follows:
(1) Small Airplane Directorate (ACE-100) in Kansas City, Missouri, responsible for regulations and policy pertaining to: a) normal, utility, and acrobatic category airplanes weighing 12,500 lbs. or less and having seating configurations, excluding pilot seats, of 9 seats or fewer, b) commuter category, (propeller driven, multiengine) airplanes weighing 19,000 lbs. or less, with seating configurations, excluding pilot seats, of 19 seats or fewer; c) manned free balloons, and d) special classes of small aircraft, including gliders, primary category airplanes, and airships (14 CFR parts 23 and 31).
(2) Transport Airplane Directorate (ANM-100) in Renton, Washington, responsible for regulations and policy pertaining to all transport category airplanes (14 CFR part 25).
(3) Rotorcraft Directorate (ASW-100) in Fort Worth, Texas, responsible for regulations and policy for normal and transport category rotorcraft (14 CFR parts 27 and
29).
(4) Engine and Propeller Directorate (ANE-100) in Burlington, Massachusetts, responsible for regulations and policy for all aircraft engines, propellers, and auxiliary power units (14 CFR parts 33 and 35).
The addresses of these Directorates are provided in Appendix 2. Aircraft certification tasks within a particular geographic area are normally handled by an Aircraft Certification Office (ACO) that reports to one of the Aircraft Certification Directorates.
c. The Aircraft Engineering Division (AIR-100) and the Production and Airworthiness Certification Division (AIR-200) in Washington, DC, develop and oversee standard application of general type, production, airworthiness certification, and continued airworthiness policies (e.g., 14 CFR parts 21, 39, and certain provisions of
183), including those related to implementation of Bilateral Airworthiness Agreements and the airworthiness provisions of Bilateral Aviation Safety Agreements. The Aircraft Engineering Division (AIR-100) also develops and oversees standard application of technical policies concerning the approval of appliances covered by a Technical Standard Order (TSO).
d. The International Policy Office (AIR-40) in Washington, DC, is responsible for policy guidance on Bilateral Airworthiness Agreements (BAA), Bilateral Aviation Safety Agreements (BASA), and other international airworthiness issues, programs, and procedures. A single staff member, APC-100, is located in Singapore and performs functions similar to those of the Brussels branch. The Brussels Aircraft Certification International Policy Branch (AEU-100) located in Brussels, Belgium, provides support in Europe, Africa and the Middle East, to the Directorates and Divisions, the Flight 2
Standards Service, foreign civil airworthiness authorities, and U.S. and foreign manufacturers.
e. In addition to the organizations within the FAA’s Aircraft Certification Service (AIR), four other FAA offices provide support for AIR’s certification responsibilities.
(1) The Office of Environment and Energy (AEE) develops, recommends, and promulgates regulations establishing standards for aircraft noise, and regulations for fuel venting and exhaust emissions for turbine engine powered airplanes.
(2) The Flight Standards Service (AFS) through its Aircraft Evaluation Groups (AEG), evaluates operational and maintenance issues for new designs and inservice products. These AEG, located at the Aircraft Certification Directorates, integrate their activities with those of the Directorates during the type certification process.
(3) The Office of International Aviation (AIA), through its five International Area Offices, provides liaison between the FAA and foreign governments.
(4) The Office of the Chief Counsel (AGC) reviews all agreements between the FAA and other authorities and provides interpretations of all regulations and procedures.
1-4. BILATERAL AGREEMENTS
a. Purpose. Bilateral agreements are cooperative agreements between the U.S.
and the government of a foreign country for their mutual benefit. The FAA’s Aircraft Certification Service has responsibility under two kinds of bilateral agreements-- Bilateral Airworthiness Agreements and Bilateral Aviation Safety Agreements with Implementation Procedures for Airworthiness. Both agreements are based on a high degree of mutual confidence in the technical competence and regulatory capability of the aviation authority of the exporting country for performing aircraft certification functions within the scope of the agreement.
b. Bilateral Airworthiness Agreement
(1) A Bilateral Airworthiness Agreement (BAA) is an executive agreement between the U.S. and a foreign country that has a competent civil airworthiness authority and an aeronautical product manufacturing industry. A BAA is not a trade agreement. Instead, it is a technical agreement concerning the performance of airworthiness certification functions. BAA’s vary in scope, but all provide that "... the importing State shall give the same validity to the certification made by (the competent aeronautical authority of the exporting State) as if the certification had been made by its (the importing country's) own competent aeronautical authority in accordance with its own applicable laws, regulations, and requirements." One condition common to all of these agreements permits the importing State to prescribe additional technical 3
conditions ". . . which the importing State finds necessary to ensure that the product meets a level of safety equivalent to that provided by its applicable laws, regulations, and requirements which would be effective for a similar product produced in the importing State." The U.S. concluded 27 BAA’s with foreign governments from 1938 through 1991. Twenty-two current BAA’s consist only of an Executive Agreement negotiated and concluded by the U.S. Department of State. Three BAA’s (with Argentina, China, and Indonesia) consist of an Executive Agreement and a Schedule of Implementation Procedures (SIP). Because modifying a BAA can be cumbersome, the U.S. has established a new, more flexible format, a Bilateral Aviation Safety Agreement, discussed below.
(2) Except for Canada, the BAA’s between the U.S. and other countries do not address FAA acceptance of maintenance work performed outside the U.S.
This AC, therefore, does not address such maintenance on U.S.-registered aircraft or on products to be installed on U.S.-registered aircraft. Separate maintenance agreements (Maintenance Implementation Procedures) with Germany, France, and Ireland have been concluded as of August 2000. Contact the Continuous Airworthiness Maintenance Division, Flight Standards Service, for more information.)
c. Bilateral Aviation Safety Agreement
(1) In order to facilitate the FAA’s need to include additional aviation safety areas in a bilateral agreement, the U.S. has established a format that separates the agreement to cooperate in the performance of civil aviation responsibilities from the technical procedures which implement that agreement. This format, called a Bilateral Aviation Safety Agreement (BASA), consists of an Executive Agreement, which is similar for all countries, and one or more Implementation Procedures (e.g., for airworthiness, maintenance, and flight simulators). Like a BAA, a BASA provides for technical cooperation between the FAA and its counterpart aircraft certificating authority, and, like a BAA, a BASA with airworthiness implementation procedures is intended to facilitate reciprocal airworthiness certification of civil aeronautical products imported or exported between the two signatory countries. A BASA, however, provides more flexibility than does a BAA and may include other procedures besides airworthiness.
(2) Countries are candidates for a BASA with the United States only if a determination has been made that its aviation regulatory system meets ICAO standards
(i.e., Category 1 of FAA’s International Aviation Safety Assessment Program).
(3) The signatories of the Executive Agreement are the Department of State and its foreign ministry counterpart, while the signatories of the Implementation Procedures (IP) are the FAA and its counterpart civil aviation authority. The FAA and its counterpart can modify or add IP’s as needed without changing the Executive Agreement. Appendix 3 lists the countries with which the U.S. has established bilateral agreements, the type of the agreement (BAA or BASA), and the scope (i.e., products eligible for U.S. acceptance) of the agreement. Because the products eligible for U.S.
import can vary from agreement to agreement, the provisions of a bilateral agreement 4
with a particular country should be carefully reviewed. The texts of BAA’s and BASA’s with IPAs are available on the Internet at: http://www.faa.gov/certification/aircraft
d. Technical Assessment Process. Before recommending a new agreement related to airworthiness, the FAA conducts a technical assessment of the certification system in the candidate BASA partner country. This assessment, which is very comprehensive, typically lasts between two and seven years. The assessment is conducted on a cost-reimbursable basis. The objective of the technical assessment is to determine whether the certification system in the BASA partner country is sufficiently comparable to the U.S. system to ensure similar results.
(1) Areas of assessment:
(a) National Legislation: The FAA reviews the scope and provisions of the partner country’s aviation regulations vis a vis the country’s legislation.
(b) Mission/Mission Priorities: The FAA reviews the mission and scope of the counterpart authority’s work program.
(c) Organization: The FAA examines the organizational structure of the partner country’s aviation authority, its delegations of authority, the location of its offices and its staffing, and its plans and mechanisms for ongoing improvement.
(d) Personnel: The FAA examines the roles, responsibility, and authority of the CAA’s personnel and the delegation of these roles and responsibilities to others.
The FAA also examines the personnel’s experience and training (including technical and on-the-job training).
(e) Approval Documents: The FAA examines the CAA’s approval documents, including design approvals, production quality assurance system approvals, airworthiness certifications, continued airworthiness documents, and delegation of responsibility documents.
(f) Standards/Policies: The FAA reviews procedural and regulation/rulemaking processes of the authority. It examines current policies, operating orders, and guidance material and reviews certification procedures. The FAA also reviews the authority's design standards and production and airworthiness regulations.
(g) Design, Production and Airworthiness Certification Processes:
The FAA reviews in detail the CAA’s design, production, and airworthiness certification processes.
(h) Certificate Management Activities: The FAA examines the CAA’s monitoring activities for certificate holders, its continued airworthiness programs, and how the authority revises and amends approvals.
(i) Enforcement: The FAA reviews the CAA’s enforcement activities, including its ability to revoke or suspend certificates, its authority to assess monetary damages, its system for determining administrative penalties, and its prohibitions on falsification of data.
(j) Communications: As part of the assessment, the FAA reviews the CAA’s internal coordination process, how the CAA coordinates with other organizations, and the means by which it communicates with manufacturers, operators, and other certificate holders.
(k) Environment: The FAA reviews the relationship between the CAA and other organizations, including the partner country’s aviation industry.
(2) Phases of Assessment: The technical assessment process for a new agreement normally consists of four phases:
(a) Familiarization. The purpose of the familiarization phase is to conduct a preliminary technical evaluation and become familiar with the CAA’s aircraft certification system. This enables the FAA to identify aircraft certification areas where the FAA may need to provide technical assistance and training in the application of airworthiness standards, practices, and procedures for the aeronautical products designed and manufactured for export to the U.S. under a BASA.
(b) Review. During this phase, the FAA conducts a more detailed review of the CAA’s aircraft certification system, especially those areas that differ from those of the U.S. During this phase, the FAA may review engineering data for any proposed shadow certification product.
(c) Shadow Certification. This is the most critical phase of the technical assessment program. During this phase, the FAA’s assessment goes beyond a document review. The FAA works side-by-side with the CAA on an actual certification project to assess how well the CAA understands FAA requirements and could apply them, on behalf of the FAA, under a BASA. The FAA monitors tests, reviews certification data, and observes meetings with the certification applicant. The FAA also determines how well the proposed design complies with U.S. requirements.
(d) Implementation Procedures for Airworthiness (IPA) Negotiation.
Following the successful completion of a technical assessment, and after a BASA Executive Agreement has been proposed to the foreign government by the U.S.
Department of State, the FAA and the CAA co-develop the details of the Implementation Procedures for Airworthiness (IPA). A BASA IPA may include procedures for the reciprocal acceptance of design approvals, production and surveillance oversight, continued airworthiness activities, design change approvals, and export airworthiness approvals. The scope of the IPA can be modified over time (e.g., expanded to cover additional activities) or changed and/or canceled without affecting the Executive Agreement or other IP’s.
1-5. HOW BILATERAL AGREEMENTS WORK 6
a. General. Title 49 U.S.C. 44704 requires the FAA to make certain “findings” or determinations of compliance to U.S. airworthiness standards before issuing a type certificate, production certificate, or airworthiness certificate. In the case of a type certificate, the FAA is required to find that the design of the product meets the U.S.
airworthiness standards applicable to the product. 49 U.S.C. 44704(d) requires the FAA to determine that a product conforms to a design previously approved by the FAA, and that it is in a condition for safe operation before issuing a U.S. airworthiness certificate for that product. The FAA Administrator may exercise discretion in how these findings will be made, the level of direct FAA involvement necessary, and what constitutes competent evidence for making the required findings.
b. Findings Process under Bilateral Agreements. The FAA makes its findings for the airworthiness certification, approval, or acceptance of civil aeronautical products imported to the U.S. by working through, and in cooperation with, the CAA of the exporting country. Generally, the FAA predicates its findings on statements from the exporting authority which certifies to the FAA that the design and performance of the product meet the U.S. or equivalent airworthiness standards; that the exported product (including complete aircraft) conforms in construction and manufacturing processes to the approved design; and, at the time of export certification by the exporting authority, that the product is determined by the exporting authority to be in a condition for safe operation.
c. Maintenance of the Bilateral Relationship. Once an agreement is negotiated, sustaining the relationship is equally important to the FAA. FAA field offices interact with other CAA’s on daily activities such as validation projects, export activities, and harmonization work. BASA IPA’s commit the FAA to meet periodically with its counterpart authority to review the IPA and any certification system changes. The FAA wants to ensure that there is a common understanding of each other’s requirements. In addition, the FAA and its partners conduct visits as needed to ensure both authorities meet the commitments they have made in their bilateral agreements. Each bilateral partner country has been assigned to an FAA Directorate for this enhanced formal cooperation. These country assignments are listed in appendix 2.
1.6 TECHNICAL ASSISTANCE AND COOPERATION BETWEEN AUTHORITIES
a. The global manufacturing environment creates challenges for the FAA and other civil aviation authorities in carrying out their regulatory duties around the world.
Upon request and after mutual agreement, the FAA and the CAA may provide technical assistance to each other when significant activities are conducted in either country.
These technical assistance activities help avoid any undue burden imposed on either authority. Types of assistance may include, but are not limited to, determination of compliance (e.g., witnessing tests, performing inspections, reviewing reports, obtaining data) and surveillance and oversight (e.g., conducting inspections on production parts, conducting investigations of service difficulties).
b. Under the U.S. Freedom of Information Act (FOIA), information the FAA has in its possession must be disclosed unless a FOIA exemption applies to that information. Exemptions include proprietary data such as trade secrets and financial or commercial information. As bilateral partners, the FAA and the CAA agree that they will not release proprietary data obtained from either authority to anyone other than an FAA or CAA employee without written consent of the design approval holder or other data submitter.
c. Upon request, the FAA and the CAA cooperate by providing information of service incidents, accidents, and suspected unapproved parts involving civil aeronautical products imported under their Implementation Procedures.
1-7. AIRWORTHINESS SAFETY OBJECTIVES AND FUNCTIONS. The procedures and practices applied by the FAA for the airworthiness certification of civil aeronautical products to be imported to the U.S. are intended to achieve four fundamental objectives, namely that:
a. The design and performance of the product meet the applicable U.S.
airworthiness and environmental standards or standards determined by the FAA to be equivalent;
b. Each particular civil aeronautical product presented for U.S. airworthiness certification, approval, or acceptance for installation on a U.S. type certificated and U.S.-registered aircraft conforms to an FAA-approved design and is in a condition for safe operation;
c. The companies responsible and the CAA having regulatory responsibility for product design integrity and manufacturing quality control are clearly defined and have adequate technical capability, so as to ensure that safety issues which may arise with the product in service will be satisfactorily resolved in a timely manner; and
d. The FAA can meet its regulatory responsibilities under Title 49 U.S.C. in administering applicable regulatory requirements of 14 CFR without undue burden.
CHAPTER 2. PRODUCT DESIGN APPROVAL PROCEDURES
2-1. GENERAL
a. Requirement for a Bilateral Agreement. Product design approvals will not be granted to an applicant located in a country with which the U.S. has not concluded a bilateral agreement for the export and import airworthiness certification of such products
(i.e., a BAA or a BASA).
b. Categories of Design Approvals. The FAA grants design approvals of civil aeronautical products to be imported to the U.S. in the following forms.
(1) Type Certificates (TC), including type certificate amendments, are issued for the design approval of aircraft, aircraft engines, and propellers.
(2) Supplemental Type Certificates (STC) are issued for approval of major changes to a type certificated design (aircraft, aircraft engines, and propellers) that are not great enough to require a new application for a type certificate. The holder of a type certificate usually has the type certificate amended for these purposes.
(3) Letters of TSO design approval are issued to approve the design of appliances to be manufactured outside the U.S., which meet the minimum performance standards of an FAA Technical Standard Order.
(4) Letters of parts design approval [reserved].
c. Application Priority. The FAA does not normally issue a type design approval for a product manufactured outside the U.S. (i.e., the state of design is other than the U.S.), unless the product is intended for use under U.S. registry or for operation by a U.S. operator under lease or charter. Approvals may be granted for engines, propellers, or appliances to be incorporated into the design of a U.S.-registered aircraft or U.S.- manufactured product. Foreign applicants for U.S. design approval should provide the FAA with evidence that the product will be imported into the U.S., or will be installed on a U.S.-registered or U.S.-manufactured product. This information, when provided at the time of application, will help the FAA to establish project priorities.
d. References to FAA Airworthiness Regulations. The FAA's procedural regulations for the design approval of products, including products imported to the U.S., are set forth in 14 CFR part 21 (part 21). Applicable airworthiness standards are set forth in:
(1) 14 CFR parts 21 through 35, for various kinds of products.
(2) A series of Technical Standard Orders (TSO) identified in the current version of AC 20-110, Index of Technical Standard Orders, for articles (parts, materials, processes, or appliances).
(3) 14 CFR parts 21 and 36 for standards concerning aircraft noise.
(4) 14 CFR part 34 for standards concerning fuel venting and exhaust emissions for turbine engine powered airplanes.
e. Relationship to International Civil Aviation Organization Airworthiness Standards. ICAO has airworthiness standards for engines, propellers, aeroplanes, and helicopters, defined in Annex 8, Airworthiness of Aircraft. The references listed in paragraph 2-1(d) above meet or exceed these ICAO requirements, except where differences have been filed with ICAO. ICAO also has aircraft noise, fuel venting, and exhaust emissions standards defined in Annex 16, Volumes I and II.
f. Applicability of U.S. Design Approvals. An FAA type design approval for a product (e.g., aircraft) is required:
(1) As a prerequisite for the issuance of a U.S. standard or certain types (i.e., primary, limited, and restricted) of special airworthiness certificates;
(2) To permit a non-U.S.-registered aircraft to be operated under lease or charter by a U.S.-certificated air carrier or commercial operator under parts 121 or 135;
or
(3) To permit certain equipment (e.g., engines, appliances) to be installed on an aircraft having a U.S. standard airworthiness certificate.
2-2. AIRCRAFT, AIRCRAFT ENGINES, PROPELLERS
a. General Airworthiness Requirements
(1) Under 49 U.S.C. 44711(a)(1), any civil aircraft registered in the U.S. must have a valid airworthiness certificate before it can be operated in air commerce. Under 49 U.S.C. 44704(d), a civil aircraft (including its engines, propellers, and installed appliances) must conform to an FAA-approved type design and be found in a condition for safe operation to be eligible for a U.S. airworthiness certificate. Also under 49 U.S.C. 44704(d), a civil aircraft must be registered in the U.S. and appropriately marked (i.e., with a registration number) before it can receive a U.S. airworthiness certificate. These statutory requirements are reflected in 14 CFR parts 21 and 45.
(2) Under 14 CFR 21.181(a)(1), a standard U.S. airworthiness certificate on an aircraft remains valid as long as maintenance/preventive maintenance and alterations are performed in accordance with 14 CFR parts 43 and 91, and the aircraft continues to be registered in the U.S. Section 43.13 requires, in effect, continuing conformity to the 10
aircraft's FAA-approved type design or properly altered configuration. Therefore, all replacement engines, propellers, materials, parts, and appliances installed on a U.S.-registered civil aircraft must be acceptable to the FAA. These requirements apply equally to U.S.-registered aircraft operated outside the U.S. and to aircraft operated within the U.S.
(3) Many civil aeronautical aircraft registered outside the U.S. (including foreign aircraft manufactured outside the U.S.) are subsequently returned to the U.S.
Design changes or repairs and modifications made on such an aircraft while that aircraft was operated on a registry of another country either must be removed and the aircraft returned to FAA-approved standards, or the changes must be approved by the FAA before a U.S. standard airworthiness certificate can be issued. Complete maintenance records, including those required by 14 CFR 91.417, must be provided and other maintenance requirements of 14 CFR parts 121 and 135 may apply which are outside the scope of this AC. Chapter 3 discusses airworthiness acceptance procedures for such aircraft.
(4) An FAA design approval (e.g., a U.S. type certificate) must be issued as a prerequisite for obtaining a production approval (e.g., production certificate).
However, an FAA production approval is not a prerequisite for issuing a U.S.
airworthiness certificate or approval. As explained in Chapter 4, the FAA does not usually issue production approvals to companies located outside of the U.S., but may extend production certificates to a facility located outside the U.S. under certain circumstances.
b. U.S. Operations
(1) An export certificate of airworthiness, issued by the airworthiness authority of an exporting country to facilitate U.S. airworthiness certification, does not constitute an authorization to operate an aircraft and, therefore, does not satisfy the requirement for a U.S. airworthiness certificate.
(2) A U.S. air carrier or commercial operator, certificated to operate under 14 CFR parts 121 or 135, may operate an aircraft under lease or charter that is not registered in the U.S., provided certain requirements are met, including establishing that the aircraft conforms to a type design approved by the FAA. The requirements that must be met in order for such aircraft to be operated are contained in 14 CFR 121.153 and 135.25.
2-3. TYPE CERTIFICATION PROCEDURES
a. General
(1) U.S. airworthiness standards for normal, utility, acrobatic, and commuter category airplanes are codified in 14 CFR part 23; standards for transport category airplanes are in 14 CFR part 25; standards for normal category rotorcraft are in 14 CFR 11