Subject: AIRWORTHINESS 

CERTIFICATION OF CIVIL AIRCRAFT, 

ENGINES, PROPELLERS, AND RELATED 

PRODUCTS IMPORTED TO THE UNITED 

STATES

11/17/2004

AIR-40

21-23B

1. PURPOSE. This advisory circular (AC) provides information on the Federal Aviation 

Administration's (FAA) objectives, regulations, and general practices for United States of 

America (U.S.) airworthiness certification or acceptance of civil aeronautical products imported 

to the U.S. It has been updated to reflect the latest Bilateral Aviation Safety Agreement 

Implementation Procedures for Airworthiness. 

2. CANCELLATION. Advisory Circular 21-23A, Airworthiness Certification of Civil Aircraft, 

Engines, Propellers, and Related Products Imported to the United States, dated 

October 20, 2000, is canceled. 

3. RELATED REGULATIONS AND ADVISORY MATERIAL

a. Title 49, United States Code (Title 49, U.S.C.), Subtitle I, Department of Transportation, 

and Subtitle VII, Aviation Programs. 

b. Title 14, Code of Federal Regulations (14 CFR), part 21, Certification Procedures for 

Products and Parts. 

c. FAA Advisory Circulars (AC) inform the aviation public of nonregulatory material of 

interest. The latest revision of the following AC’s provide detailed guidance and information to 

applicants for design approval of imported products: 

(1) AC 00-2.15, Advisory Circular Checklist and Status of Other FAA Publications; 

(2) AC 00-44, Status of Federal Aviation Regulations; 

(3) AC 20-62, Eligibility, Quality, and Identification of Aeronautical Replacement Parts; 

(4) AC 20-110, Index of Aviation Technical Standard Orders; 

(5) AC 21-12, Application for U.S. Airworthiness Certificate, FAA Form 8130-6; 
AC 21-23B 11/17/04 

(6)AC 21.17-1, Type Certification – Airships; 

(7)AC 21.17-2, Type Certification – Fixed Wing Gliders (Sailplanes) Including Powered 

Gliders; 

(8)AC 21.17-3, Type Certification of Very Light Airplanes under FAR 21.17(b); 

(9) AC 21-20, Supplier Surveillance Procedures;

(10) AC 21-24, Extending a Production Certificate to a Facility Located in a Bilateral 

Airworthiness Agreement Country; 

(11) AC 21-27, Production Certification Multinational/Multicorporate Consortia; 

(12) AC 21-28, Airworthiness Certification of U.S. Produced Aircraft and Engine Kits 

Assembled Outside the United States; 

(13) AC 21-29, Detecting and Reporting Suspected Unapproved Parts; 

(14) AC 21-37, Primary Category Aircraft; and 

(15) AC 45-2, Identification and Registration Marks. 

AC 00-2.15, Advisory Circular Checklist and Status of Other FAA Publications, provides 

ordering information for all ACs. AC 00-2.15 and other free AC’s may be ordered from: 

U.S. Department of Transportation 

Subsequent Distribution Office 

Ardmore East Business Center 

3341 Q 75th Avenue 

Landover, MD 20785 

Requests for copies can be faxed to 301/386-5394. AC 00-2.15 is also available via the Internet 

at: http://www.airweb.faa.gov/Regulatory_and_Guidance_Library

d. FAA Orders prescribe the responsibilities and procedures for FAA personnel. The latest 

revision of the following Orders provide detailed guidance and information to applicants for 

design and production approval: 

(1) Order WA 0000.5, Washington Headquarters Directives Checklist; 

(2) Order 8110.4, Type Certification Process; 

(3) Order 8100.5, Aircraft Certification Directorate Procedures; 

(4) Order 8100.7, Aircraft Systems Evaluation Program; 

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11/17/04 AC 21-23B 

(5) Order 8100.14, Interim Procedures for Working with the European Community on 

Airworthiness Certification and Continued Airworthiness 

(6) Order 8110.10, FAA Approvals of Major Modifications/Alterations; 

(7) Order 8110.42, Parts Manufacturer Approval Procedures;

(8) Order 8120.2, Production Approval and Certificate Management Procedures; 

(9) Order 8120.10, Suspected Unapproved Parts Program; 

(10) Order 8130.2, Airworthiness Certification of Aircraft and Related Products; 

(11) Order 8130.20, Registration Requirements for the Airworthiness Certification of U.S. 

Civil Aircraft; 

(12) Order 8130.21, Procedures for Completion and Use of FAA Form 8130-3, 

Airworthiness Approval Tag; 

(13) Order 8130.27, Certification and Operation of Aircraft under the Experimental 

Purpose(s) of Research and Development; 

(14) Order 8150.1, Technical Standard Order Procedures; and 

(15) Order 8300.10, Airworthiness Inspectors Handbook. 

Consult AC 00-2.15 to obtain ordering information for these publications. 

4. DEFINITIONS

a. Airworthiness Directives (AD) are substantive regulations issued by the FAA in 

accordance with 14 CFR part 39. An AD is issued when (1) an unsafe condition has been found 

to exist in a particular aircraft, aircraft engine, propeller, or appliance, and (2) that condition is 

likely to exist or develop in other aircraft, aircraft engines, propellers, or appliances of the same 

type design. Once an AD is issued, no person may operate a product to which the AD applies 

except in accordance with the requirement of that AD. 

b. Appliance is any instrument, mechanism, equipment, part, apparatus, appurtenance, or 

accessory, including communications equipment, that is used or intended to be used in 

operating or controlling an aircraft in flight, is installed in or attached to the aircraft, and is not 

part of an airframe, aircraft engine, or propeller. 

 

c. Bilateral Airworthiness Agreement (BAA) means a government-to-government 

executive agreement between the U.S. and the government of another country (contracting 

State) to facilitate the airworthiness approval or acceptance of civil aeronautical products 

exported from one contracting State to the other. BAA’s are not trade agreements; rather, they 

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AC 21-23B 11/17/04 

are technical cooperation agreements, intended to provide a framework for the airworthiness 

authority of the importing State to give maximum practicable credit to airworthiness certification 

functions performed by the airworthiness authority of the exporting State using its own domestic 

certification system. 

d. Bilateral Aviation Safety Agreement (BASA) means a government-to-government 

agreement, consisting of one Executive Agreement and one or more Implementation 

Procedures, to facilitate the recognition of procedures for the reciprocal acceptance of: 

(1) Airworthiness approvals of civil aeronautical products; 

(2) Environmental approval and environmental testing; 

(3) Approval and monitoring of maintenance facilities and alteration or modification 

facilities; 

(4) Approval and monitoring of maintenance personnel; 

(5) Approval and monitoring of crews; 

(6) Approval and monitoring of flight operations; 

(7) Flight simulator qualification evaluations; and 

(8) Approval and monitoring of aviation training establishments. 

These agreements are replacing BAA’s. 

e. Civil Aeronautical Product (herein also referred to as “product”) means any civil aircraft, 

aircraft engine, or propeller or subassembly, appliance, material, part, or component to be 

installed thereon. 

f. Environmental Standards means the regulations governing the certification of designs 

with regard to noise characteristics, fuel venting, and exhaust emissions of civil aeronautical 

products. 

g. Implementation Procedures for Airworthiness (IPA) means the procedural document 

authorized by the BASA Executive Agreement for design approval, production activities, export 

airworthiness approvals, post-design approval activities and technical assistance between 

authorities. This document defines the civil aeronautical products and parts eligible for import 

into the U.S. and the counterpart BASA signatory country. It defines the interface requirements 

and activities between the authorities for the import and continued support of those civil 

aeronautical products. 

h.Imported to the U.S., as used within the context of this AC, means, for aircraft, a foreign 

manufactured aircraft intended to be placed on the U.S. registry. For all other foreign 

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11/17/04 AC 21-23B 

manufactured products, means intended for installation on a U.S.-registered aircraft even 

though the aircraft in either case is not operated in the U.S. (Guidance on special airworthiness 

certification is found in other FAA advisory materials.) 

i. Maintenance Implementation Procedures means the procedural document authorized 

by the BASA Executive Agreement related to the performance of maintenance, alterations and 

modifications on civil aeronautical products. This document defines the process for reciprocal 

acceptance of each authority's recommendations for the certification, renewal, and acceptance 

of eligible repair stations and maintenance organizations. 

j. New 

 

( 1) For an aircraft, means an aircraft that is still owned by the manufacturer, distributor, 

or dealer, if there is no intervening private owner or lease or time-sharing arrangement, and the 

aircraft has not been used in any pilot school and/or commercial operation. 

 

(2) For an aircraft engine or propeller, means an aircraft engine or propeller that is still 

owned by the manufacturer, distributor, or dealer; and has never been installed on an aircraft, 

has no time in service other than testing by the manufacturer, and meets all technical 

requirements for a new product. 

k. Rebuilt Product means a product that uses new or used parts that conform to new part 

tolerances and limits or to approved oversized or undersized dimensions that has undergone 

the following by the original manufacturer: 

( 1) Has been disassembled, cleaned, inspected, repaired as necessary, and 

reassembled to the extent possible; and 

( 2) Has been tested to the same tolerances and limits as a new product. 

l. Schedule of Implementation Procedures (SIP) means the procedural document, similar 

to an IPA that is associated with some BAA’s. It facilitates the approval process for aircraft and 

other aeronautical products being imported or exported between the U.S. and a foreign country. 

m. Used means an aircraft, engine, or propeller that is not new, as defined in paragraph (j) 

above. 

5. ABBREVIATIONS

a. ACO: FAA Aircraft Certification Office 

b. AEG: Aircraft Evaluation Group 

c. ATC: Additional Technical Condition 

d. BAA: Bilateral Airworthiness Agreement 

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AC 21-23B 11/17/04 

e. BASA: Bilateral Aviation Safety Agreement 

f. CAA: Civil Aviation Authority 

g. CFR: U.S. Code of Federal Regulations 

h. FAA: Federal Aviation Administration, U.S.A. 

i. ICAO: International Civil Aviation Organization 

h. ICAW: Instructions for Continued Airworthiness 

i. IP: Implementation Procedures (BASA) 

j. IPA: Implementation Procedures for Airworthiness 

k. JAA: Joint Aviation Authorities 

n. MIP: Maintenance Implementation Procedures 

l. MMEL: Master Minimum Equipment List 

p. PC: Production Certificate 

q. SFAR: Special Federal Aviation Regulation 

q. SIP: Schedule of Implementation Procedures 

r. STC: Supplemental Type Certificate 

t TC: Type Certificate 

s. TSO: Technical Standard Order 

v. TSOA: Technical Standard Order Authorization 

w. USC: United States Code 

6. GENERAL

a. The FAA does not issue standard airworthiness certificates, nor grant airworthiness 

approvals, for aeronautical products manufactured in a country with which the U.S. does not 

have a BAA or a BASA with IPA for the kinds of products concerned. The FAA must issue a 

type certificate prior to the issuance of an FAA standard airworthiness certificate. 

b. Information provided in this AC is intended to offer guidance for the most common 

situations encountered in the design approval process leading to FAA type certification or 

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11/17/04 AC 21-23B 

issuance of letter of TSO design approval, and to FAA airworthiness certification or approval of 

civil aeronautical products to be imported to the U.S. Procedures and practices dealing with 

unique situations should be cleared in advance with the Aircraft Certification Service, FAA 

Headquarters, Washington, D.C. 

c. Suggestions or comments for future revision of this AC should be addressed to the 

Director, Aircraft Certification Service, Federal Aviation Administration, 800 Independence 

Avenue, SW., Washington, D.C. 20591. 

 John Hickey 

Director, Aircraft Certification Service 

vii (and viii) 

11/17/04 AC 21-23B 

CONTENTS 

Paragraph Page 

CHAPTER 1. INTRODUCTION

 1-1. GENERAL 1 

 1-2. AIRCRAFT CERTIFICATION SERVICE’S INTERNATIONAL 

 VISION AND MISSION 1 

 1-3. FAA AIRCRAFT CERTIFICATION SERVICE ORGANIZATION 1 

 1-4. BILATERAL AGREEMENTS 3 

 1-5. HOW BILATERAL AGREEMENTS WORK 7 

 1-6. TECHNICAL ASSISTANCE AND COOPERATION 

 BETWEEN AUTHORITIES 7 

 1-7. AIRWORTHINESS SAFETY OBJECTIVES AND FUNCTIONS 8 

CHAPTER 2. PRODUCT DESIGN APPROVAL PROCEDURES 

 2-1. GENERAL 9 

 2-2. AIRCRAFT, AIRCRAFT ENGINES, PROPELLERS 10 

 2-3. TYPE CERTIFICATION PROCEDURES 11 

2-4. TC AMENDMENTS AND STC’S 22 

2-5. ACTIONS TO TRANSFER, SURRENDER, OR REVOKE AN FAA TYPE 

 CERTIFICATE 23 

2-6. DESIGN APPROVAL PROCEDURES FOR APPLIANCES -- FAA LETTER 

 OF TSO DESIGN APPROVAL 24 

2-7. LETTER OF PARTS DESIGN APPROVAL [RESERVED] 25 

FIGURE 2-1. EXAMPLES OF TECHNICAL DATA, BY PRODUCT, NORMALLY 

REQUESTED BY THE FAA FOR TYPE 

CERTIFICATION 26

FIGURE 2-2. EXAMPLES OF TECHNICAL DATA NORMALLY REQUIRED 

 BY THE FAA FOR SUPPLEMENTAL TYPE CERTIFICATION 27 

CHAPTER 3. AIRWORTHINESS APPROVAL OF IMPORTED PRODUCTS

3-1. GENERAL 29 

3-2. AIRCRAFT 31 

3-3. AIRCRAFT ENGINES, PROPELLERS, MATERIALS, PARTS AND 

APPLIANCES (RELATED PRODUCTS) 35 

3-4. REBUILT PRODUCTS 37 

3-5. SPECIAL MAINTENANCE RECORDS CONSIDERATION 37 

3-6.-3-9. [RESERVED] 37 

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AC 21-23B 11/17/04 

Paragraph Page 

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) 

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11/17/04 AC 21-23B 

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 

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AC 21-23B 11/17/04 

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 

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11/17/04 AC 21-23B 

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 
AC 21-23B 11/17/04 

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 

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11/17/04 AC 21-23B 

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. 

5 
AC 21-23B 11/17/04 

(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

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11/17/04 AC 21-23B 

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).

7 
AC 21-23B 11/17/04 

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. 

8 
11/17/04 AC 21-23B 

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. 

9 
AC 21-23B 11/17/04 

(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 
11/17/04 AC 21-23B 

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 
AC 21-23B 11/17/04 

part 27; standards for transport category rotorcraft are in 14 CFR part 29; standards for 

manned free balloons are in 14 CFR part 31; standards for aircraft engines are in 

14 CFR part 33; and standards for propellers are in 14 CFR part 35. 

(a) For certain special classes of aircraft for which standards have not 

been issued by the FAA under 14 CFR Subchapter C, such as gliders, airships, and 

nonconventional aircraft, the applicable requirements will be those portions of parts 23, 

25, 27, 29, 31, 33, and 35 found by the Administrator to be appropriate for the aircraft 

and applicable to a specific type design, or such airworthiness criteria as the 

Administrator may find provides an equivalent level of safety to those parts. (See 

14 CFR 21.17(b).) 

(b) 14 CFR 21.24 provides for the issuance of type certificates for primary 

category aircraft manufactured either in the U.S. or manufactured in a country with 

which the U.S. has a bilateral agreement and imported to the U.S. 

(2) 14 CFR part 21 provides for issuance of type certificates under either 

the procedures of 14 CFR 21.21 for approval of U.S.-manufactured products, or 14 CFR 

21.29 for approval of products to be imported to the U.S. The procedures for issuance 

of these type certificates are different; once issued, however, both type certificates have 

equal status and validity. The major difference in these procedures is how FAA’s 

findings are made. Under 14 CFR 21.21, the FAA or its designees determine that the 

design meets the necessary requirements. Under 14 CFR 21.29, the FAA's findings are 

generally based on technical evaluations, inspections, and certifications made for the 

FAA by the exporting CAA of the applicant’s country. 

(3) Under 14 CFR 21.29, a type certificate may be issued for an aircraft, 

engine, or propeller manufactured in a foreign country with which the U.S. has a 

bilateral agreement for the acceptance of these products for import (and that is to be 

imported into the U.S.) if: 

(a) The original exporting CAA (where the product was 

manufactured) certifies to the FAA that the product has been examined, tested, and 

found to meet the applicable airworthiness, noise, fuel venting, and exhaust emissions 

standards established by the FAA or by the exporting CAA (with any other noise, fuel 

venting and exhaust emission requirements prescribed by the FAA Administrator) for 

the product; 

(b) The applicant has submitted the required technical data

concerning aircraft noise and airworthiness; 

(c) The manuals, placards, listings, and instrument markings

required by applicable airworthiness requirements are presented in the English 

language; and 

12 
11/17/04 AC 21-23B 

(d) The applicant has submitted the technical data required by the 

FAA (reference figure 2-1). 

 

(4) The applicant must show that the airworthiness and environmental 

requirements applied by the exporting CAA for U.S. certification will provide compliance 

with the U.S. type certification basis. 

(5) Design approvals for major changes and alterations (including model 

changes) to products will usually be issued in the form of an amendment to the existing 

TC (or letters of TSO design approval) or as an STC (see Section 2-4). 

(6) Minor changes, product design improvements, or service instructions

(e.g., service bulletins, structural repair manuals, supplemental structural inspection 

documents) other than those described in paragraph 2-3(a)(4) will be considered FAA 

approved, if approved by the exporting CAA under its normal procedures. However, 

service bulletins or other similar instructions classified as "mandatory" by the exporting 

CAA are not mandatory in the U.S. regulatory system unless required by an FAA AD. 

(7) For products imported from a JAA member country, the FAA/JAA Type 

Validation Principles should be followed for FAA type certification. 

b. Primary Category Aircraft. Under 14 CFR 21.24, a type certificate may be 

issued for a primary category aircraft manufactured in a foreign country with which the 

U.S. has a bilateral agreement and from which the aircraft is to be imported into the 

U.S. if the CAA of the exporting country certifies to the FAA that: 

(1) The applicant has completed the engineering analysis necessary to 

demonstrate compliance with the applicable airworthiness requirements; 

(2) The applicant has conducted appropriate flight, structural, 

propulsion, and systems tests necessary to show that the aircraft, its components, 

and its equipment are reliable and function properly; 

(3) The type design complies with the airworthiness standards and noise 

requirements established for the aircraft under 14 CFR 21.17(f); 

(4) No feature or characteristic makes the aircraft unsafe for its intended 

use; 

(5) The required manuals, placards, listings, instrument markings, and 

documents are submitted in English; and 

(6) Other requirements as established by 14 CFR 21.24 (a) and (b) are 

met. 

13 
AC 21-23B 11/17/04 

c. Application for FAA Type Certification 

(1) An application for a U.S. TC, in accordance with 14 CFR 21.15, should be 

sent to the exporting CAA. Applications may be submitted for products that already 

were issued an exporting CAA TC, or for products where application for type 

certification has been made to that exporting CAA. The exporting CAA should ensure 

the application to the FAA has the following information: 

(a) The exporting CAA’s Type Certificate and TC Data Sheet, if 

available, a definition of the national airworthiness and environmental standards upon 

which the authority’s design approval was (or is to be) based, and the U.S. 

airworthiness and environmental standards the authority believes to be satisfied by its 

own standards. 

(b) A description of all novel or unusual design features known to the 

applicant or the exporting CAA at the time of application which might necessitate 

issuance of FAA special conditions under 14 CFR 21.16 or 21.101, or which might 

require a special review of acceptable means of compliance; 

(c) All known or expected exemptions or equivalent level of safety

findings relative to the exporting CAA’s national standards for design approval that 

might affect compliance with the applicable U.S. airworthiness and environmental 

standards. 

(d) A planning date for FAA type certification; and 

(e) Available information on U.S. market potential, including specific 

customers and U.S. content of the product, if known. 

(2) Except for Canadian products, the exporting CAA should forward 

applications to the Aircraft Certification Service Directorates as follows: 

(a) Small and commuter category airplanes, manned free balloons, 

and special classes of small aircraft, including gliders, primary category

airplanes, and airships, to the Small Airplane Directorate in Kansas City, Missouri; 

(b) Transport category airplanes to the Transport Airplane Directorate in 

Renton, Washington; 

(c) Normal and transport category rotorcraft to the Rotorcraft 

Directorate in Fort Worth, Texas; and 

(d) Engines and propellers to the Engine and Propeller Directorate in 

Burlington, Massachusetts. Appendix 2 contains a list of addresses for the FAA Aircraft 

Certification Service Directorates. NOTE: For Canadian products, see the Canadian 

IPA. 

14 
11/17/04 AC 21-23B 

(3) If the application is for a product in a category not previously

certificated by the exporting CAA, or the product is of a level of complexity that has not 

been previously certificated by the exporting CAA, the exporting CAA should notify the 

FAA of that fact. This notification should be made as soon as the exporting CAA 

becomes aware of this type of pending application, so that the FAA may plan the scope 

of its validation program. 

d. FAA Technical Involvement. In accordance with the bilateral agreement, the 

FAA's technical involvement in the design approval (particularly, the issuance of type 

certificate and type certificate amendments) is intended to accomplish the following 

functions: 

(1) To provide for FAA familiarity with the general design, performance, and 

operational characteristics of the product for which U.S. type certification or design 

approval is sought, for the purpose of establishing the U.S. certification basis to the 

extent necessary, and for FAA to meet its post-certification responsibilities after the 

product enters service on the U.S. registry; 

(2) To establish the U.S. type certification basis and the means of 

compliance for the product under application by determining the U.S. airworthiness and 

environmental standards that would be applied to a similar product if it were to be 

produced in the U.S.; 

(3) To understand the airworthiness certification system (including the 

airworthiness and environmental standards, policies, and certification practices) applied 

by the exporting authority in their domestic certification of the product. This will include 

an understanding of the level of exporting CAA involvement with prototype conformity 

inspections, tests, and flight programs; 

(4) To compare the airworthiness and environmental standards, policies, 

and practices applied by the exporting authority in their domestic certification with the 

U.S. type certification basis or design requirements and certification policies and 

practices; 

(5) To define and explain any additional technical conditions that should 

be met for FAA certification to provide for equivalency with the applicable U.S. 

airworthiness and environmental standards; 

(6) To maintain sufficient liaison and technical dialogue with the exporting 

authority to ensure that technical questions and issues which might affect U.S. 

certification of the product are identified and resolved between the FAA and the 

exporting authority as early as possible; and 

(7) To provide for effective management of the certification project and 

for the most cost-effective utilization of FAA's resources on the project. 

15 
AC 21-23B 11/17/04 

e. FAA Project Management. The FAA Directorate, upon receipt of an 

application for a type certificate will establish where project management responsibility 

will reside. The FAA will give high priority to the establishment of the project 

management office and notification to the exporting authority. The FAA will notify the 

exporting CAA of the Project Manager. 

f. Communications. An applicant for an FAA type certificate may request 

technical meetings or may correspond directly with the FAA to discuss and resolve 

technical issues that may arise in the certification program. However, because the FAA 

relies heavily on the exporting CAA's understanding of FAA's position on such issues, it 

is imperative that the exporting CAA is included in any such meetings or 

correspondence. The FAA will normally seek the exporting CAA's opinions before 

significant issues are resolved and may decline to meet with the applicant to discuss 

and resolve technical issues unless the exporting CAA is adequately represented at the 

meeting. Similarly, correspondence will usually be answered through, coordinated with, 

or copied to the exporting CAA. 

g. Familiarization Briefing.

(1) The FAA will notify the exporting CAA prior to each familiarization 

meeting. As part of this notification, the FAA will identify special requirements and 

issues related to the specific aeronautical product that must be addressed by the 

exporting CAA and the foreign applicant. The exporting CAA should acknowledge 

FAA’s notification and advise FAA whether it is able to support an FAA validation team 

during the requested period. 

(2) The exporting CAA should arrange a familiarization meeting with the 

FAA, the exporting CAA, and the applicant to discuss the product design, including all 

novel or unusual features of the product, the validation process, and the approved or 

proposed domestic exporting CAA certification basis. The meeting should also identify 

any operational safety issues associated with the product. For products with a prior 

service history, but not previously type certificated by the FAA, the applicant and the 

exporting CAA should plan to brief the FAA on the product's service history, including 

corrective measures taken to preclude reoccurrence of incidents or accidents. 

(3) The meeting should be held at a location mutually agreeable to the 

exporting CAA, the FAA, and the applicant. 

(4) At this meeting the FAA will work to establish the U.S. type 

certification basis and the means of compliance for the product under application by 

determining the U.S. airworthiness and environmental standards that would be applied 

to a similar product if it were to be produced in the U.S. The extent to which these 

activities are accomplished at the meeting will depend on the FAA’s familiarity with the 

product and applicant, the applicant’s familiarity with the FAA’s process and, in general, 

the overall preparedness of all parties. 

16 
11/17/04 AC 21-23B 

(5) The composition of the Project Certification Team should be addressed 

at the familiarization meeting. The composition of the team should include specialist 

representation that reflects the technology level of the certification project. The FAA 

and the exporting CAA will mutually agree on a plan to ensure adequate compliance 

finding capability. 

(6) For engines, propellers, and less complex aircraft projects, technical 

familiarization may be streamlined if agreed by both authorities. 

h. Additional Technical Meetings 

(1) In addition to the initial familiarization meeting, other technical 

meetings may be necessary to ensure that any additional technical conditions that have 

been communicated to the exporting CAA are well understood, and that any 

outstanding technical issues are resolved. These meetings should be held as early as 

possible in the certification process in order to avoid last minute design changes. All 

technical meetings will normally be arranged through the exporting CAA and will 

normally have both authorities’ representatives in attendance. 

(2) Early in the program, based on the known design and information 

presented in the familiarization and technical meetings, the FAA will identify the areas in 

which further activity will be required (e.g. required data, reports, tests and test 

witnessing, areas of concern or special emphasis). The FAA’s anticipated level of 

activity will be documented in writing. This agreement may be revised if the initial 

design definition is incomplete or subsequent design changes are made. 

(3) During the type certification program the FAA may request additional 

technical design data, may review the product, and may fly the product for 

familiarization purposes. In addition, the FAA may request data or briefings on the 

design to advise the exporting CAA on acceptable means of compliance with the U.S. 

type certification basis. 

i. Establishment of the U.S. Type Certification Basis 

(1) New type certificates. The FAA certification basis is established for the 

product in accordance with 14 CFR part 21. The certification basis includes the 

applicable airworthiness standards, found in 14 CFR parts 23, 25, 27, 29, 31, 33, and 

35, and environmental standards, found in 14 CFR parts 34 and 36. The date of 

application to the FAA determines the U.S. type certification basis, unless otherwise 

provided in the applicable bilateral agreement. The applicable bilateral agreement 

should be consulted before establishing FAA’s certification basis. 

(a) In certifying that an applicant’s design meets the requirements for a 

U.S. TC, the exporting CAA may find compliance with the: 

17 
AC 21-23B 11/17/04 

(i) Applicable U.S. airworthiness standards in effect on the date of 

application for the U.S. TC and environmental standards in effect on the date of U.S. 

type certification; or 

(ii) The exporting CAA’s domestic airworthiness and 

environmental standards and all other airworthiness requirements the FAA may 

prescribe to provide a level of safety equivalent to the U.S. airworthiness standards in 

effect on the date of application for U.S. type certification, and environmental 

requirements the FAA may prescribe to provide noise, fuel venting, and exhaust 

emission levels that are no greater than those provided by the U.S. environmental 

standards in effect on the date of U.S. type certification. 

(b) If the foreign type certification basis precedes the FAA certification 

basis, the exporting CAA must consider the U.S. regulatory changes that have occurred 

since the date of application for the exporting CAA’s TC. In general, the FAA may 

require the applicant to comply with additional technical conditions in the interests of 

safety. These additional technical conditions identify important applicable regulatory 

differences between the requirements and regulations of the exporting CAA and those 

of the FAA. Such differences include those that have significant impact on 

airworthiness, design, operational limitations, and operating characteristics, and those 

that have significant differences in means of compliance. Additional technical conditions 

may include policies, special conditions, and mandatory airworthiness actions taken to 

correct unsafe conditions. 

(2) Additional requirements/special conditions. The FAA will also review all 

novel and unusual design features for development of special conditions, if any. FAA 

special conditions are an integral part of the U.S. type certification basis. 

(a) The FAA issues special conditions under 14 CFR 21.16 and 21.101 

if the FAA finds that the applicable U.S. airworthiness standards do not contain 

adequate or appropriate safety standards for an aircraft, aircraft engine, or propeller 

because of a novel or unusual design feature of the product. FAA special conditions 

are issued through the public rulemaking procedures of 14 CFR part 11 and contain 

such safety standards for the particular product as the FAA finds necessary to establish 

a level of safety equivalent to that established in the applicable FAA airworthiness 

standards. FAA special conditions issued for products exported to the U.S. are the 

same as would be issued for a similar product produced in the U.S. 

(b) The FAA will work closely with the exporting CAA in the 

development of special conditions and processing of exemptions in order to provide the 

opportunity for the exporting CAA to coordinate, and the applicant to comment on the 

proposed special conditions. Such coordination will allow the FAA to benefit from the 

technical expertise of the exporting CAA and allow the exporting CAA to better 

understand how to make a finding of compliance, if so requested by the FAA. 

(3) Environmental (Type) Certification Basis. The regulatory basis for 

compliance with 14 CFR parts 34 and 36 is the effective amendment on the date of FAA 

certification. An applicant for a TC, amended TC, or STC should show that the product 

18 
11/17/04 AC 21-23B 

meets applicable airworthiness standards, special conditions, fuel venting and exhaust 

emission standards of 14 CFR part 34, and the noise standards of 14 CFR part 36. 

(4) Development of Additional Technical Conditions (ATC). The FAA 

finding that the product meets the U.S. type certification basis will rely, to a great extent, 

on the exporting CAA’s certification of compliance to FAA requirements. If the exporting 

CAA elects to certify compliance with its own national standards and additional FAA 

technical conditions, this choice should be established by the exporting CAA early in the 

project so that the necessary comparisons of national standards can be completed and 

the additional FAA technical conditions can be established. The diagram below 

illustrates how the U.S. type certification basis can be determined: 

 Applicant’s National Standards 

 + 

 FAA Additional Technical Conditions 

 equals U.S. Type 

Certification Basis 

 or 

 

 U.S. Standards 

 U.S. Type 

Certification Basis equals 

(a) If the findings of compliance are to the applicable U.S. standards, 

the FAA will not develop any ATC’s. 

(b) If the findings of compliance are to the exporting CAA’s 

standards, the FAA may specify ATC’s as a condition for FAA approval of the type 

design. These ATC’s will account for: 

(i) Differences in the basic airworthiness and environmental 

standards of the U.S. and the exporting state; 

(ii) Noncompliance with the exporting CAA’s airworthiness or 

environmental standards because of exemptions or equivalent safety findings granted 

by the exporting CAA for its own domestic certification (provided there is a similar U.S. 

requirement); 

(iii) Special conditions issued by the FAA under 14 CFR 21.16 or 

21.101 because of a novel or unusual design feature of the product that are not required 

in an equivalent manner by the exporting CAA’s airworthiness standards; 

(iv) Mandatory airworthiness actions (i.e., AD’s) directed by the 

exporting CAA to correct unsafe conditions experienced during operation prior to 

application for FAA approval; and 

19 
AC 21-23B 11/17/04 

(v) Optional conditions identified by the FAA to assist any eventual 

U.S. operator to comply with current U.S. operational or maintenance requirements. 

(5) Changes to type certificates. The FAA certification basis for a change to 

a product is established in accordance with 14 CFR part 21. 

(6) Application period. 14 CFR 21.17(c) specifies an application for type 

certification of a transport category aircraft is effective for 5 years and an application for 

any other type certificate is effective for 3 years. After that time period, compliance with 

later requirements may be necessary. In the case of certification of an imported 

product, these time periods may not be applicable if other provisions are included in a 

specific bilateral agreement. For example, where the imported product was certificated 

by the exporting CAA several years earlier, the certification basis may essentially be 

frozen at the original date of application in the exporting State if a bilateral agreement 

provides for this. 

(7) Project Updating. Throughout the course of the project, the FAA will rely 

on the exporting CAA to advise them of the following developments: 

(a) Novel or unusual design features that become apparent during 

design development that could necessitate: amendment of the U.S. type certification 

basis, the issuance of special conditions, or special discussions with the FAA on 

acceptable means of compliance; 

(b) Previously specified changes to the exporting CAA’s certification 

basis, to include exemptions, etc., that could alter the FAA’s additional requirements or 

special conditions; and 

(c) The need for FAA equivalent safety findings or exemptions from the 

U.S. type certification basis that may become apparent and are considered justified by 

the exporting CAA during design development. 

j. Data Submittal & Design Review

(1) Technical data varies with the type and complexity of the product. 

Consequently, the project management office may request additional data to establish 

the U.S. type certification basis and to become familiar with unique design features or 

manufacturing processes. The items listed in Figure 2-1 are examples of the technical 

data normally requested. 

(2) The applicant should submit data to the exporting CAA for verification 

and transmittal to the FAA. 

k. Issue Papers. An issue paper provides a means for the identification and 

resolution of significant technical, regulatory, and administrative issues that occur during 

20 
11/17/04 AC 21-23B 

the certification process. The FAA will coordinate all issue papers and changes to issue 

papers with the exporting CAA. Such coordination will expedite the timely and mutually 

acceptable resolution of certification issues. 

l. Environmental Approval

(1) Environmental Testing and Approval Procedures. The FAA is 

authorized to make findings of compliance to 14 CFR parts 34 and 36 based on FAAwitnessed tests conducted in accordance with FAA-approved test plans, and on FAA 

review and approval of all data and compliance demonstration reports submitted via the 

exporting CAA. 

(2) Environmental Testing and Approval Process. The typical process for 

environmental testing and approvals should consist of the following actions: 

(a) The applicant should submit environmental (noise, fuel venting, 

and exhaust emissions) compliance demonstration plans to the FAA for review, 

comment, and subsequent approval prior to undertaking U.S. environmental certification 

testing. 

(b) The FAA, before issuing an original type certificate for an aircraft 

of any category, will assess the extent of noise abatement technology incorporated into 

the type design and determine whether additional noise reduction is achievable. The 

applicant should supply information and data as soon as possible after the application 

for type certification in each original type certification project and reflect noise reduction 

potentials that become evident during the design and certification process. 

(c) The FAA conducts an evaluation of the measurement and analysis 

methods and practices, and data correction procedures of the applicant for aircraft noise 

certification under 14 CFR part 36, subparts B and H.

(d) Aircraft noise test plans and engine exhaust emissions test 

plans to be used for demonstrating U.S. environmental certification compliance should 

be submitted to the FAA for review and comment, and subsequent approval not less 

than 90 days prior to commencing testing. 

(e) Proposed equivalent procedures to be used by the applicant 

during testing, data processing, data reduction, and data analysis should be specifically 

identified to the FAA and approved in advance by the FAA as part of items l.(2)(a) and 

l.(2)(d) above. 

(f) FAA personnel or FAA designated engineering representatives

will witness compliance demonstration tests. Prior to the start of testing it is necessary 

to ensure the conformity of the test article (i.e., aircraft or engine configuration) to that 

identified in the FAA approved compliance demonstration test plans. Witnessing these 

tests is not delegated to the exporting CAA, unless specific bilateral agreement 

provisions have been implemented regarding environmental approvals. 

21 
AC 21-23B 11/17/04 

(g) The FAA will review and comment on compliance demonstration 

reports. Approval of these reports will precede type certification approval. 

m. Final Certification Meeting/Issuance of the Type Certificate. Upon 

issuance of its domestic TC and demonstrated compliance with the U.S. Type 

Certification basis, the exporting CAA should forward a certifying statement to the FAA, 

in accordance with 14 CFR 21.29(a)(1), as well as all additional requested materials. 

The FAA, upon receipt and review of the documents, will prepare the TC and TC Data 

Sheet and forward them to the exporting CAA for transmittal to the applicant. A final 

meeting will be necessary only if there are areas of further discussion or if the sharing of 

information would be beneficial. 

n. Evaluation of U. S. Operational and Maintenance Aspects. The FAA has 

established Aircraft Evaluation Groups (AEGs) located at the product-accountable 

Directorates. The AEGs are responsible for the Operational and Maintenance aspects 

of the Type Certification process. 

(1) The AEG will conduct boards, as appropriate, on the foreign country’s 

products prior to their entry into U. S. operations. These Boards will be used to review: 

1) the Maintenance Review Board (MRB) Report and associated Instructions for 

Continued Airworthiness (ICAW) documentation; 2) operational configuration, pilot 

training and licensing requirements; product maintainability; and 3) the formulation and 

approval of a Master Minimum Equipment List (MMEL). The AEG will be invited to 

participate in the familiarization meeting by the FAA Project Manager and will generate 

issue papers as appropriate to the type design. Compliance with AEG requirements for 

Instructions for Continued Airworthiness is required at the time of issuance of the 

product’s first U.S. standard airworthiness certificate (see 14 CFR 21.50(b)). 

(2) The AEG will also review and make recommendations concerning the 

acceptability of the Aircraft Flight Manual and maintenance manuals against U.S. 

operational requirements. These AEG activities are not part of the design approval 

process; however, AEG staff will integrate their activities to the maximum extent 

practicable with the design approval activities to ease the burden on all concerned. It is 

in the applicant's best interest to cooperate and work with the AEG, because this will, in 

turn, assist U.S. operators in meeting FAA operational requirements (under 

14 CFR parts 91, 121, 135, etc.). 

2-4. TC AMENDMENTS AND STC’s

a. The type certificate procedures and interrelationships described above 

also apply to TC Amendments and STC’s (if included in a bilateral agreement). The 

basic design approval procedures for U.S. type certification should be used for STC’s, 

but the certification procedure may be adjusted as appropriate for the magnitude and 

complexity of the design change. Figure 2-2 lists examples of technical data normally 

requested for supplemental type certifications. 

22 
11/17/04 AC 21-23B 

b. Unless specifically covered by the applicable bilateral agreement, the FAA 

does not issue STC’s to non-U.S. applicants located outside the country where the 

affected aircraft, engine, or propeller was manufactured, because of the undue burden 

of administering the applicable requirements. 

c. When included in a BASA IPA, applications for STC’s shall be forwarded to 

the FAA office responsible for the original FAA type certificate/validation of the product. 

Application packages should include a full description of the major change and the 

proposed certification basis. If the application is for validation of an STC already issued 

by the exporting authority, the application package should include a statement certifying 

that the STC complies with FAA requirements for the product. If the application is for an 

STC project that is concurrently being evaluated by both the FAA and the exporting 

authority, the certifying statement by the exporting authority may be made at the end of 

the project. 

2-5. ACTIONS TO TRANSFER, SURRENDER, OR REVOKE AN FAA TYPE 

CERTIFICATE 

a. General. ICAO guidelines provide for the transfer of continued airworthiness 

responsibilities to the new type design holder and its CAA when a TC moves between 

countries. Transfer of ICAO state of design responsibilities for TC’s and STC’s to or 

from the United States may only be accomplished for those products within the scope of 

the bilateral Implementation Procedures established between the FAA and the CAA. 

Further, transfer of state of design responsibilities for STC’s may only be accomplished: 

1) when a bilateral agreement specifically provides for acceptance of state of design 

responsibilities for STC’s; 2) for major changes to products within the scope of those 

bilateral Implementation Procedures; and 3) when the CAA has issued a type certificate 

or equivalent for the product being transferred. It is the option of the importing CAA 

whether or not to accept ICAO state of design responsibilities. It is important for 

industry to understand these conditions when contemplating the international sale or 

purchase of a type certificate. 

b. Transfer of a Foreign TC or STC to a Person in the U.S.

(1) The FAA will accept ICAO state of design responsibilities for TC and 

STC transfers only from countries with which the U.S. has a bilateral agreement. Upon 

notification of a transfer or transfer request from the CAA type certificate holder to a 

U.S. applicant, the CAA should notify the product-accountable Directorate to establish 

procedures for the efficient transfer of the ICAO state of design responsibilities for the 

TC or STC to the U.S. Each transfer will be accomplished on a case-by-case basis 

through a special arrangement which identifies each authority’s responsibilities in the 

transfer process. 

(2) The CAA should provide support to establish that the certificated 

product complies with the applicable requirements of the U.S. airworthiness regulations. 

The CAA should provide the FAA with a compliance statement for the TC or STC 

23 
AC 21-23B 11/17/04 

certifying that the applicable requirements of the U.S. airworthiness regulations have 

been met. 

(3) Upon transfer of ICAO state of design responsibilities or at an agreedupon date, the FAA product-accountable Directorate will become responsible for 

complying with the continued airworthiness requirements of ICAO, Annex 8 to the 

Chicago Convention, Airworthiness of Aircraft, for the affected product, and will notify all 

member countries of the change in state of design responsibility. Responsibilities 

pursuant to the Chicago Convention will not extend to products that have not been 

found to meet the U.S. type design. 

c. Surrender, Revocation, or Suspension of TC or STC. BASA IPA’s also 

provide procedures in cases where a TC or an STC is surrendered, revoked, or 

suspended. These procedures provide for immediate written notification and assurance 

of continued airworthiness responsibility to support the continued operational safety of 

the fleet. 

2-6. DESIGN APPROVAL PROCEDURES FOR APPLIANCES -- FAA LETTER OF 

TSO DESIGN APPROVAL

a. The FAA will issue a letter of TSO design approval only to manufacturers 

located in a country with which the U.S. has concluded a bilateral agreement applicable 

to the appliance in question. The exporting CAA is responsible for oversight of both the 

design and production of such appliances. 

b. An applicant for a FAA letter of TSO design approval should apply through 

the exporting CAA with a request that the application and required data be forwarded to 

the FAA. The exporting CAA should contact the FAA for information concerning the 

latest FAA technical policy and procedures whenever the CAA receives an application 

for an FAA letter of TSO design approval to a TSO performance standard for which the 

CAA has not previously made compliance findings. 

c. The FAA issues a letter of TSO design approval only for appliances of a kind 

for which a minimum performance standard has been published in an FAA Technical 

Standard Order (TSO) after: 

(1) Receipt of all required data pertaining to the proper installation, 

performance, operation, and maintenance of the appliance; 

(2) Receipt of other specific technical data requested by the FAA 

pertaining to the proposed installation, performance, operation, and maintenance of the 

appliance; 

(3) Receipt and approval of any proposed deviation; and 

24 
11/17/04 AC 21-23B 

(4) Receipt of a certifying statement from the exporting CAA that the 

appliance has been examined, tested, and found to meet the applicable FAA TSO or 

agreed upon standards that provide an equivalent level of safety. 

d. The FAA design approval of appliances for which the U.S. airworthiness 

standards (minimum performance standards) are established in an FAA TSO can 

usually be accomplished by correspondence, as long as a complete data package has 

been forwarded by the exporting CAA. The TSO language should be carefully reviewed 

to ensure that all applicable data has been generated and submitted. 

e. Installation Approval. An FAA Letter of TSO Design Approval does not 

constitute an installation approval for the TSO appliance on an aircraft. The installer 

must obtain installation approval from the applicable or cognizant authority for use on an 

aircraft registered by that authority. 

2-7. LETTER OF PARTS DESIGN APPROVAL (RESERVED)

25 
AC 21-23B 11/17/04 

FIGURE 2-1. EXAMPLES OF TECHNICAL DATA, BY PRODUCT, 

NORMALLY REQUESTED BY THE FAA FOR TYPE CERTIFICATION

1. AIRCRAFT. 

 a. A statement of the applicable U.S. design certification standards. 

 b. General interior arrangement configuration drawings. 

c. Three-view drawing (exterior configuration). 

 d. Master drawing list. 

 e. Master equipment list. 

f. Aircraft Flight Manual (including the Configuration Deviation List, if applicable). 

 g. Instructions for Continued Airworthiness. 

 h. Certification compliance (checklist). 

 i. Data and descriptive information needed by the FAA to approve/publish the type 

certificate data sheet.1/

 j. Listing of service life for critical parts subject to fatigue, if this information is not 

provided elsewhere in the above data. 

2. AIRCRAFT ENGINES. 

 a.Cross-section arrangement drawing. 

 b.Master drawing list. 

c. Instructions for Continued Airworthiness. 

 d.Operating manual. 

 e.Installation manual. 

f.Certification compliance (checklist). 

 g.Data and descriptive information needed by the FAA to prepare the type certificate 

data sheet.1/

 h.Listing of service life for critical parts subject to fatigue, if this information is not 

provided elsewhere in the above data. 

3. PROPELLERS. 

 a.General arrangement drawings and model description. 

b. Master drawing list. 

c. Installation manual. 

 d.Instructions for Continued Airworthiness. 

 e.Operating manual. 

f.Certification compliance (checklist). 

 g.Data and descriptive information needed by the FAA to prepare the type certificate 

data sheet.1/

 h.Listing of service life for critical parts subject to fatigue, if this information is not 

provided elsewhere in the above data. 

____________ 

1/

May be presented in the form of a draft type certificate data sheet prepared by the applicant. 

26 
11/17/04 AC 21-23B 

FIGURE 2-2. EXAMPLES OF TECHNICAL DATA

NORMALLY REQUESTED BY THE FAA FOR SUPPLEMENTAL TYPE CERTIFICATION

ALL PRODUCTS 

 a.Certification compliance checklist 

b. Aircraft Flight Manual supplement 

c. Master documentation list 

 d.Master drawing list. 

 e.Manufacturing and installation instruction drawings 

f. Maintenance/repair manual supplements 

 g.Weight and balance data 

 h.Instructions for Continued Airworthiness. 

27 (and 28) 

11/17/04 AC 21-23B 

CHAPTER 3. AIRWORTHINESS APPROVAL OF IMPORTED PRODUCTS

3-1. GENERAL

a. Aircraft and related products manufactured outside of the U.S. being 

imported to the U.S. may be eligible for FAA airworthiness acceptance, if they have 

received some form of FAA design approval and are accompanied by an export 

certificate of airworthiness or equivalent certifying statement issued by the CAA of the 

country of manufacture, or by the exporting CAA of a "third country," in accordance with 

the provisions of a bilateral agreement, as discussed in paragraph 3-2(e). 

(1) Export certificates of airworthiness or other certifying statements, 

issued by either the FAA or an exporting CAA, officially document the airworthiness 

condition of the exported product. These certificates may facilitate airworthiness 

certification by the authority of the new country of registry, but do not constitute 

"airworthiness certificates" within the meaning of 49 U.S.C. 44704(d) or 14 CFR part 21, 

Subpart H. 

(2) Any deviations from the FAA-approved design must be noted on the 

certifying statement. Any such deviation must be resolved by the installer before the 

product is eligible for installation approval on U.S. type certificated and U.S.-registered 

aircraft, or on an engine or propeller to be installed on a U.S. type certificated and U.S.-

registered aircraft. In no case may any aircraft be operated unless there is an 

appropriate airworthiness certificate or special flight permit issued to and valid for that 

aircraft. 

b. FAA airworthiness approvals for civil aeronautical products to be imported 

to the U.S. are generally handled in the following manner: 

(1) U.S. Airworthiness Certificates are issued for the approval of complete 

aircraft in accordance with the procedures outlined in paragraph 3-2 below. 

(2) New aircraft engines, propellers, appliances and parts thereof are 

considered to meet the regulatory requirements for approval when the product is 

accompanied by a certification from the appropriate exporting authority, attesting that 

the product conforms to the FAA-approved design and is in a condition for safe 

operation as outlined in paragraph 3-3 below. 

c. The FAA requirements for the airworthiness approval of civil aeronautical 

products imported to the U.S. are set forth in the following regulations. 

(1) Aircraft. 14 CFR part 21, subpart H, establishes the procedural 

requirements for U.S. airworthiness certification of complete aircraft. These regulations 

apply to both new and used aircraft that do not already have a U.S. airworthiness 

certificate. 

 29 
AC 21-23B 11/17/04 

(a) 14 CFR 21.183(c) pertains to the issuance of U.S. standard 

airworthiness certificates for import aircraft type certificated by the FAA under 14 CFR 

21.29 and may be applied to aircraft type certificated under the provisions of 14 CFR 

21.21 but manufactured outside the U.S. (e.g., under a licensing agreement). 

(b) 14 CFR 21.183(d) pertains to the issuance of U.S. standard 

airworthiness certificates to other aircraft imported to the U.S. and type certificated by 

the FAA, such as used aircraft. 

(c) 14 CFR 21.184(b) pertains to the issuance of special 

airworthiness certificates for primary category aircraft imported into the U.S. that 

have been type certificated by the FAA under 14 CFR 21.29. Such an aircraft is eligible 

for a Special Airworthiness Certificate if the exporting CAA of the country in which the 

aircraft was manufactured issues a certifying statement that the aircraft conforms to an 

approved type design that meets the criteria of 14 CFR 21.24 (a)(1) and is in a condition 

for safe operation. 

(d) 14 CFR 21.185(c) pertains specifically to the issuance of U.S. 

restricted category airworthiness certificates to aircraft imported to the U.S. which 

have been type certificated by the FAA in the restricted category under the provisions of 

14 CFR 21.29. 

(e) 14 CFR 21.190(d) pertains specifically to the issuance of special 

airworthiness certificates for light-sport aircraft manufactured outside the United 

States. Aircraft certificated under this section must be manufactured in a country with 

which the U.S. has a BAA concerning airplanes, a BASA IPA concerning airplanes or an 

equivalent airworthiness agreement. Additionally, the aircraft must be eligible for an 

airworthiness certificate, flight authorization, or similar certification in its country of 

manufacture. 

(2) Other Aeronautical Products. 14 CFR part 21, subpart K, prescribes 

procedural requirements for the approval of materials, parts, processes, and appliances. 

14 CFR part 21, subpart N, establishes the procedural requirements for airworthiness 

approval or acceptance of aircraft engines, propellers, materials, parts, and appliances 

manufactured outside the U.S., including appliances for which a "letter of TSO design 

approval" has been issued under 14 CFR part 21, subpart O (21.601(b)(3) and 21.617). 

d. Alteration, modification or repairs made to an aircraft or related product that 

are not in accordance with FAA accepted or approved data require coordination and 

approval of the FAA. 

30 
11/17/04 AC 21-23B 

3-2. AIRCRAFT

a. Requirements for U.S. Airworthiness Certification

(1) FAA Regulations. FAA regulations concerning issuance of airworthiness 

certificates for U.S.-registered aircraft (new or used) are contained in 14 CFR part 21, 

Subpart H. Most of the requirements apply to aircraft manufactured either within or 

outside the U.S. Additional requirements in 14 CFR parts 36, 39, 45, 47, 49, and 91 

(described below) must also be met before the aircraft can be certificated or operated in 

the U.S. 

(2) U.S. Registration. A valid U.S. registration must be issued by the Civil 

Aviation Registry in Oklahoma City, OK, and, except for those aircraft to which the 

provisions of 14 CFR 45.22(a) or (b) apply, appropriate nationality and registration 

marks ("N" numbers) must be displayed on the aircraft before a U.S. airworthiness 

certificate in any category may be issued. Evidence of de-registration from the foreign 

registry, if appropriate, and U.S. registration is required prior to the issuance of a U.S. 

airworthiness certificate. FAA requirements for U.S. registration are established in 

14 CFR part 47. The recording of aircraft titles and security documents is addressed by 

14 CFR part 49. Aircraft nationality and registration marking requirements are 

contained in 14 CFR part 45, Subpart C. 

(3) Aircraft Identification. Prior to the issuance of a U.S. airworthiness 

certificate, the aircraft must have an identification plate in accordance with 

14 CFR 21.182, which meets the requirements of 14 CFR part 45, subpart B. 

Subpart B also contains requirements for marking aircraft engines and propellers. 

(4) Noise and Emissions Requirements. In addition to meeting the 

airworthiness standards, an aircraft must meet the noise standards of 14 CFR 21.93(b), 

21.183(e) or 21.185(d), Part 36, and operating requirements of part 91, subpart I, as 

applicable. The emissions standards of 14 CFR part 34, if applicable, must also be met 

to be eligible for a U.S. airworthiness certificate. 

(5) Approved Flight Manuals, Markings, and Placards. The aircraft must be 

accompanied by an approved flight manual in the English language if a manual is 

identified on the FAA type certificate data sheet. Also, the aircraft must have the 

appropriate English language markings and placards specified in the FAA type 

certificate data sheet, flight manual, or other approved manual materials for operations 

as required by 14 CFR 91.9 (a) and (b), a current weight and balance report, and a list 

of installed equipment. Additional requirements are specified in 14 CFR 21.5 (a). 

(6) Logbooks and Maintenance Records. Aircraft must be accompanied by 

the necessary logbooks and maintenance and alteration records as specified in 14 CFR 

part 91, subpart E, to determine the status of required inspections, life limits, etc. 

(7) Airworthiness Directives. Maintenance records, as specified in 

14 CFR 91.417, must show that the aircraft complies with all applicable FAA AD’s 

31 
AC 21-23B 11/17/04 

issued under 14 CFR part 39. The records required by 14 CFR 91.417 would satisfy 

that requirement. 

(8) Aircraft Location. A U.S. airworthiness certificate is not issued to an 

aircraft located outside the U.S., unless the FAA finds no undue burden in administering 

the applicable regulations. Procedures have been established to use the services of the 

exporting CAA of the country of manufacture, or FAA-appointed designees, to mitigate 

the burden of completing U.S. airworthiness certification of aircraft located outside the 

U.S. A potential applicant for U.S. airworthiness certification should consult with the 

FAA to determine whether such services are possible in the applicant’s particular 

situation before the applicant makes firm commitments for the issuance of a U.S. 

airworthiness certificate on an aircraft located outside the U.S. 

b. Application for a U.S. Airworthiness Certificate

(1) Application for a U.S. airworthiness certificate should be made by the 

registered owner (or an agent of the owner) on an FAA Form 8130-6, "Application for 

Airworthiness Certificate." AC 21-12, “Application for U.S. Airworthiness Certificate, 

FAA Form 8130-6,” describes the details of the application. 

(2) Approved flight manuals, logbooks, and maintenance records should 

not be submitted to FAA, but should be made available for examination by the FAA 

upon request. 

c. FAA Airworthiness Determination 

(1) Title 49 U.S.C. 44704 (d) requires the FAA to make a finding that the 

aircraft under application conforms to an FAA type certificate (i.e., an FAA-approved 

type design), and that it is in a condition for safe operation before the FAA issues a U.S. 

airworthiness certificate for an aircraft. The FAA may base its findings, wholly or 

partially, on a certification (e.g., an export certificate of airworthiness) issued by the 

exporting CAA, provided a bilateral agreement which provides for such acceptance 

exists between the U.S. and the other country. 

(2) 14 CFR 21.183(c) and 21.185(c) provide that an "import aircraft," i.e., an 

aircraft type certificated under the procedures of 14 CFR 21.29, may be eligible for a 

U.S. airworthiness certificate in the appropriate category (e.g., standard or restricted) if 

the exporting CAA of the country of manufacture certifies, and the FAA finds, that the 

aircraft conforms to a design configuration approved under the applicable FAA type 

certificate and is found to be in a condition for safe operation. 

d. CAA Export Certifications

(1) CAA certifications should be made by issuance of an export certificate of 

airworthiness which contains the certification statement noted on the corresponding 

FAA type certificate data sheet or a certification that the aircraft meets its FAA-approved 

type design and is in a condition for safe operation. The FAA expects that the aircraft 

32 
11/17/04 AC 21-23B 

will have been fully assembled and flight-tested, and the engines and propellers will be 

performance tested, before a CAA export certificate is issued. 

(2) The FAA will not normally issue a U.S. airworthiness certificate for an 

aircraft manufactured outside of the U.S. when no export certification is available. To 

be acceptable, aircraft manufactured outside of the U.S. must be controlled under 

bilateral procedures with assurance of conformity and condition provided by the 

exporting CAA in the country of manufacture. Without assurance in the form of an 

export certificate or a certifying statement from the exporting CAA of the country of 

manufacture, there is no practical way for an applicant to show, or for the FAA to find, 

conformance with the FAA-approved design and condition for safe operation. 

(3) Various types of export certification documents are utilized by the 

exporting CAA. In some cases, these certifications may be in the form of an official 

exporting CAA certificate or may be made based on airworthiness forms signed by 

private persons, when so authorized by the exporting CAA. The FAA will accept various 

types of certifications, provided they represent a certification from the appropriate 

exporting CAA attesting conformity to the U.S. type design and condition for safe 

operation of the particular product being exported and are appropriately endorsed by 

the exporting CAA or a duly authorized designee (the CAA of the exporting country 

should confirm a designee's scope of authority when so requested by the FAA). These 

certifications serve to comply with the requirements for an export certificate of 

airworthiness for the purpose of 14 CFR 21.500 or 21.502 so long as the product is 

within the scope of the applicable bilateral agreement. In those instances where the 

certifying language differs from that stated in paragraph 3-2(d)(1), the FAA will request 

an explanatory letter from the exporting authority. 

e. Used Aircraft from Third Countries 

(1) When a used aircraft is being exported to the U.S. from a country other 

than the country of manufacture, the FAA will accept export certificates of airworthiness 

issued by the exporting CAA: 

(a) Provided that the bilateral agreements between the U.S. and the 

exporting country and between the U.S. and the country of manufacture contain the 

appropriate provisions for the acceptance of products produced in another country with 

which both the U.S. and the exporting country have bilateral agreements (i.e., “third 

country” provisions); and 

(b) When the exporting CAA certifies that the aircraft conforms to its 

FAA-approved type design and is found to be in a condition for safe operation. In such 

cases, the FAA considers it incumbent upon the authority issuing the export certificate 

to consult with both the CAA of the country of manufacture and the FAA to ensure that it 

has adequate knowledge of the type design approved by the FAA. Configuration 

variations, modifications, and major repairs that are not FAA-approved should be 

33 
AC 21-23B 11/17/04 

identified, and FAA approval for these deviations should be obtained before the 

exporting CAA issues its export certificate of airworthiness. 

(2) The application for a U.S. airworthiness certification in these cases 

should cite 14 CFR 21.183(d) or 21.185(b) as the basis for certification. Although these 

regulations do not specifically require an exporting CAA’s certification, such 

certifications may be the only practicable way for the applicant to show, and for the FAA 

to find, conformity to the FAA-approved type design and that the aircraft is in a condition 

for safe operation. These procedures also apply in those instances where the bilateral 

agreement with the exporting country does not contain a "third country" provision when 

the export certificate of airworthiness issued by the exporting CAA is endorsed by the 

CAA of the country of manufacture. 

 

(3) The procedures of paragraph 3-2 (d) may also be applied for U.S.-

manufactured aircraft being returned from a registry of another country for U.S. 

registration and airworthiness certification, provided the bilateral agreement between 

the U.S. and the last country of registry contain "third country" provisions. 

(4) FAA inspections of a used aircraft may be conducted to determine that 

changes or modifications have not been made, and that the condition of the aircraft has 

not deteriorated subsequent to export certification by the exporting CAA. If the aircraft 

has been disassembled and reassembled subsequent to export certification by the 

exporting authority, flight testing may be required prior to issuance of a U.S. 

airworthiness certificate. 

(5) Cases may exist where it is impractical to obtain a U.S. airworthiness 

certificate for an aircraft that has been operated on the registry of another country 

subsequent to the issuance of an export certificate of airworthiness by the CAA of the 

country of manufacture. This includes U.S.-manufactured aircraft being returned to the 

U.S. registry. Before a U.S. airworthiness certificate can be issued: 

(a) Applicants for the U.S. airworthiness certificate should assure 

themselves that they will be able to identify repairs and modifications and document the 

equipment installed and maintenance accomplished on the aircraft between the period 

of time the export certificate was issued and the date of application for the U.S. 

airworthiness certificate; and 

(b) An applicant must show that the aircraft has remained in, or has 

been returned to, its FAA-approved design configuration and is in a condition for safe 

operation. This may involve extensive inspections by designees, certificated persons, 

the exporting CAA of the country of manufacture, the aircraft manufacturer, or others, as 

appropriate, before a U.S. airworthiness certificate can be issued. 

f. Aircraft Manufactured Outside the U.S. to a Design Not Approved by the 

FAA. Where an aircraft manufactured outside the U.S. was originally exported to a 

country other than the U.S., and the CAA of the country of manufacture has issued an 

34 
11/17/04 AC 21-23B 

export certificate attesting to conformance to a design other than that approved by the 

FAA, such certificates may be useful to the applicant to establish a baseline for showing 

conformity to the U.S.-approved design after modification. In these cases, or when the 

export certificate of airworthiness may not be available, the applicant should obtain the 

following: 

(1) A statement from the CAA of the country of manufacture which 

certifies that, when originally exported from that country, the aircraft met an FAAapproved design and/or identifies any differences between the configuration identified in 

their original export certification and the FAA-approved design; and 

(2) The technical data necessary to convert the aircraft to its FAA-approved 

design configuration. This method may involve extensive inspections by designees, 

certificated persons, the CAA of the country of manufacture, the aircraft manufacturer, 

etc., as appropriate, before the applicant is in a position to show conformity to the FAAapproved design and condition for safe operation. Attempts to obtain a U.S. 

airworthiness certificate via this method may prove to be impracticable for the applicant. 

In some instances, the applicant may ultimately be unable to obtain the desired U.S. 

airworthiness certificate. 

3-3. AIRCRAFT ENGINES, PROPELLERS, MATERIALS, PARTS AND APPLIANCES 

(RELATED PRODUCTS)

a. Airworthiness Acceptance – New Aircraft Engines and Propellers 

(1) 14 CFR 21.500 provides for the airworthiness acceptance of aircraft 

engines or propellers manufactured outside of the U.S. for which a U.S. type 

certificate has been issued. Such products are considered approved for installation on 

a U.S.-registered aircraft when a current export certificate of airworthiness has been 

issued by the exporting CAA of the country of manufacture which certifies that the 

engine or propeller: 

(a) Conforms to its U.S. type certificate and is found to be in a 

condition for safe operation; and 

(b) Has been subjected to a final operational check by the 

manufacturer. 

b. Airworthiness Acceptance – New Materials, Parts, and Appliances 

(1) 14 CFR 21.502(a) provides for the airworthiness acceptance of 

materials and parts (e.g., replacement/modification parts) manufactured in a foreign 

country with which the U.S. has an agreement for the acceptance of these materials 

and parts, when the country of manufacture issues a certificate of airworthiness for 

export certifying that the individual material or part conforms to FAA-approved design 

and is in a condition for safe operation. Parts imported into the U.S. are eligible for 

35 
AC 21-23B 11/17/04 

installation on U.S.-registered aircraft in accordance with the applicable FAA-approved 

design. 

(2) 14 CFR 21.502(a) also provides for the airworthiness acceptance of 

appliances and their parts manufactured in a foreign country with which the U.S. has 

an agreement for the acceptance of those appliances and their parts. Neither an FAA 

letter of TSO design approval nor a Certificate of Airworthiness for Export issued by the 

CAA of the country of manufacture conveys installation approval. Installation approval 

for a TSO product or part should be obtained, in a manner acceptable to the FAA, at the 

time of installation on a U.S. registered product. 

(3) A key phrase in 14 CFR 21.502(a) is that the product must be 

“manufactured in a foreign country with which the U.S. has an agreement for the 

acceptance of those materials, parts, or appliances for export and import.” Generally, 

the U.S. does not have bilateral agreements that address all parts. Excluding the 

agreements between the U.S. and Canada and the U.S. and Germany, the present 

bilateral agreements between the U.S. and other countries only permit the import of 

materials, parts, components, subassemblies, etc., in support of the bilateral partner 

country’s exported Class I products (e.g., aircraft, aircraft engine or propeller) or TSO 

appliances. (See appendix 4). Imported materials, parts and appliances must be 

directly traceable back to an FAA-approved design. 

(4) The BASA IPA between the FAA and Transport Canada (TCCA) 

recognizes the equivalence of U.S. Parts Manufacturer Approvals and Canadian 

replacement parts approvals (via STC for replacement parts or repair design 

certifications with a manufacturing approval). These parts, when accompanied by 

TCCA Authorized Release Certificates in accordance with the BASA IPA, are eligible for 

import and installation on a U.S. product. 

c. Airworthiness Acceptance – Used Engines, Propellers, Materials, Parts, 

and Appliances. Bilateral agreements do not include the reciprocal acceptance of 

used engines, propellers, materials, parts, or appliances. Any U.S. acceptance of used 

engines, propellers, materials, parts or appliances is dependent upon satisfying 

applicable FAA airworthiness and maintenance requirements. In addition, for imported 

items, acceptance of these imported items, when new, must have been within the scope 

of a bilateral agreement. 

d. Identification and Marking 

(1) Aircraft, aircraft engines, and propellers must be identified in a 

manner specified in 14 CFR 45.11. 

(2) Critical components of a product must be identified with a part 

number (or equivalent) and serial number (or equivalent), as required in 14 CFR 45.14. 

(3) Appliances and articles of a design approved by an FAA letter of TSO 

design approval must be marked in accordance with the requirements specified in 

14 CFR part 21, subpart O, and any additional marking requirements specified in the 

36 
11/17/04 AC 21-23B 

particular TSO. Approved deviations shall be marked by the holder of the TSO design 

approval on the TSO appliance or noted in attached limitations. 

(4) Parts to be used as replacement or modification parts should be 

identified by a part number, serial number if applicable, and the manufacturer's name or 

trademark. In addition, information concerning the model designation and the type 

certificated product for which the part is eligible for installation should be furnished. If 

the bilateral agreement permits production of parts to a U.S. STC design, those parts 

should be marked with the U.S. STC number, as size permits. If size does not permit, 

information should accompany each part that identifies the applicable STC. This 

information can be included on the appropriate airworthiness release document. AC 20-

62 -- Eligibility, Quality, and Identification of Aeronautical Replacement Parts –

prescribes the eligibility, quality, and traceability of aeronautical replacement parts.

3-4. REBUILT PRODUCTS. Rebuilt products are not eligible for import to the U.S. 

14 CFR 43.3(j) limits rebuilding to manufacturers that hold FAA production approvals to 

manufacture aircraft, aircraft engines, propellers, or appliances. As a matter of policy, 

the FAA does not issue approvals to manufacture these products outside the U.S. 

3-5. SPECIAL MAINTENANCE RECORDS CONSIDERATION. The information 

provided in paragraphs 3-1 through 3-3 above apply to aircraft or related products

intended for operation under the General Operating and Flight Rules of 14 CFR part 91. 

U.S. operators, such as those certificated by the FAA for operation under 14 CFR 

parts 121, 125, and 135, are required to acquire, retain, and record sufficient 

maintenance information on aircraft and related products. This enables an operator to 

integrate the aircraft or related product into its own FAA-approved maintenance 

program. This can prove difficult for U.S. operators unless the records are complete 

and are either written in English or can be translated into English. Operators and 

potential U.S. operators of imported aircraft, including used U.S.-manufactured aircraft, 

should realize that an FAA airworthiness certificate does not automatically render an 

aircraft or product eligible for operation. FAA operating requirements may specify the 

need for additional maintenance records, inspections and tests, and the installation of 

instruments and equipment not specified in the basic airworthiness certification 

requirements. 

3-6.-3-9. (RESERVED)

37 (and 38) 

11/17/04 AC 21-23B 

CHAPTER 4. PRODUCTION APPROVALS 

4-1. GENERAL. FAA approval of a U.S. manufacturer's production quality control 

system facilitates FAA airworthiness certification, approval, or acceptance of products 

manufactured at that facility. These production quality control system approvals support 

the manufacturer's obligation to ensure that the products delivered from the facility 

conform to the approved design and are in a condition for safe operation. For products 

manufactured outside the U.S., the bilateral agreement is based on FAA confidence in 

the production quality control system of a bilateral partner. The export certification of 

airworthiness from the CAA of a country with which the U.S. has a bilateral agreement 

serves the same purpose as the FAA’s certification. Therefore, the FAA does not 

normally issue production approvals outside the U.S. 

4-2. MANUFACTURING LIMITATIONS RELATED TO A BILATERAL AGREEMENT

a. Any U.S. manufacturer may propose to use the services of a foreign 

supplier or subcontractor to furnish components (materials, parts, or subassemblies) 

for use on products, which are, or may be, certified or approved (i.e., production or 

prototype). Such proposals will be reviewed by the FAA in accordance with 

14 CFR 21.43, 21.137, 21.303(g), and 21.601(c). 

b. A U.S. manufacturer may propose to use suppliers and subcontractors in 

any country for the manufacture of components without benefit of bilateral agreements, 

provided the U.S. manufacturer holds an FAA production approval including an FAA 

approved quality control or fabrication inspection system to adequately verify that 

components produced in those countries conform to the manufacturer’s approved 

design data. The FAA will not, however, permit direct shipment from a supplier or 

subcontractor located in a country that does not have a bilateral agreement with the 

U.S., unless the Administrator finds no undue burden on the U.S. in administering the 

applicable requirements of 14 CFR part 21. These procedures are explained more fully 

in AC 21-20, Supplier Surveillance Procedures. 

c. A U.S. manufacturer may use a supplier located in a country with which 

the U.S. does not have a bilateral agreement only if the authorities of that country 

would not inhibit, in any manner, an evaluation of the supplier by the FAA and that 

evaluation does not create an undue burden for the FAA to administer. Assurance of 

access should be provided to the U.S. manufacturer by both the supplier and the 

government of the country in which the supplier is located. This assurance of access 

should be made available to the FAA. If access is at any time obstructed or denied, the 

U.S. manufacturer will be instructed by the FAA to cease using the supplier. 

4-3. EXTENSIONS OF FAA PRODUCTION APPROVALS TO COUNTRIES OUTSIDE 

THE U.S.

a. The FAA may extend a Production Certificate to include a facility located 

outside the U.S. when: 1) production takes place in a country with which the U.S. has a 

bilateral agreement; and 2) the CAA of that country is willing to conduct the necessary 

 39 
AC 21-23B 11/17/04 

surveillance at facilities located in their country on behalf of the FAA. Guidance related 

to extensions is contained in AC 21-24, Extending a Production Certificate to a Facility, 

Located in a Bilateral Airworthiness Agreement Country, and in the applicable country’s 

BASA IPA. 

b. When a production approval has been granted or extended by the FAA or 

CAA of a country of manufacture, the approving authority will be fully responsible for the 

surveillance and oversight of the manufacturing facilities, wherever located, including a 

"third country." 

4-4. PRODUCTION UNDER LICENSE TO A U.S. APPROVAL HOLDER

a. The FAA or CAA of country of manufacture may grant a production 

approval in their respective countries based on design data obtained through licensing 

agreement with a TC holder in the other country. In this case the authority granting that 

production approval would ensure that: 

(1) Adequate manufacturing processes and established quality control 

procedures exist to ensure that each product conforms to its approved licensed design 

data; and 

(2) A process exists that specifies who has design authority and ensures 

that the design approval holder and its CAA approves all design changes made by the 

licensee. 

b. Production approvals based on licensing agreements will be addressed on 

a case by case basis in accordance with a BASA IPA. 

4-5. CAA SURVEILLANCE ASSISTANCE ON BEHALF OF THE FAA

a. If a U.S. manufacturer uses a supplier in a country with which the U.S. 

has a bilateral agreement, the FAA may utilize the country’s CAA for surveillance 

activities and/or inspection as a means of determining that the product or service 

provided by the supplier meets the type design, and that the supplier is adhering to the 

U.S. manufacturer’s quality requirements. When the CAA in a country with which the 

U.S. has a bilateral agreement is requested by the FAA to conduct surveillance 

activities or conformity inspection(s) at a supplier's facility, the U.S. manufacturer will 

incur all charges that the CAA may impose to accomplish the request(s). 

b. FAA production approval and supplier surveillance programs are 

described in FAA Order 8120.2, Production Approval and Certificate Management 

Procedures, AC 21-20, Supplier Surveillance Procedures, and FAA Order 8100.7, 

Aircraft Certification Systems Evaluation Program. 

40 
11/17/04 AC 21-23B 

 

CHAPTER 5. CONTINUED AIRWORTHINESS

5-1. GENERAL

a. Bilateral agreements provide for close cooperation between countries in 

the resolution of safety issues that can arise from in-service operation of any product 

exported/imported and approved or accepted under the terms of the agreement. When 

a safety concern arises, the FAA cooperates with its partner to determine the 

appropriate corrective action to be taken by operators or owners of affected 

U.S.-registered aircraft. The FAA expects exporting CAA’s to keep it informed of 

corrective actions that they believe are required for the safety of U.S.-registered aircraft. 

b. The FAA also works closely with its counterpart authority to approve 

changes to type designs. These changes may consist of design improvements, 

changes necessary for continued airworthiness, repair information, or customer options. 

5-2. CONTINUED AIRWORTHINESS DOCUMENTS

a. Continued Airworthiness Service documents (e.g., service bulletins, 

structural repair manuals, supplemental structural inspection documents), approved by 

the airworthiness authority of the country where an affected product is manufactured, 

are considered to be FAA-approved unless otherwise noted in a specific bilateral 

agreement. However, service bulletins or other similar instructions classified as 

"mandatory" by the exporting CAA are not mandatory under 14 CFR unless required by 

an FAA AD. 

b. Owners or operators of affected U.S.-registered aircraft or engines, 

propellers, appliances and parts (i.e., products) are not required under U.S. law to 

comply with service documents or directives issued by the airworthiness authorities of 

other countries unless an FAA AD is issued under 14 CFR part 39. FAA AD’s are 

published in the Federal Register. AD’s issued during the current calendar year are 

available on the Internet at http://av-info.faa.gov. Information for ordering ADs can also 

be obtained from the FAA’s Delegation & Airworthiness Programs Branch, AIR-140, 

P.O. Box 26460, Oklahoma City, Oklahoma, 73125. 

c. The FAA is committed to sharing safety critical information as soon as 

possible with its bilateral partners. FAA maintains an automated data-base of all 

service difficulty reports received from the aviation community, including reports on 

imported products. This data is available on the Internet at http://av-info.faa.gov. 

d. The FAA has filed an official difference with ICAO over the ICAO 

requirement for states to require that a system exists to transmit continuing 

airworthiness information to type design organizations. (See ICAO Annex 8, Part II, 

paragraph 4.2.5.) Instead, the FAA shares significant information with the certificating 

41 
AC 21-23B 11/17/04 

authority. In addition the FAA makes its Service Difficulty Reporting (SDR) system 

database available on the Internet at the address listed in c. above. 

5-3. NOTIFICATION OF UNSAFE CONDITION AND MANDATORY CONTINUING 

AIRWORTHINESS ACTIONS

a. When an exporting CAA issues a mandatory continuing airworthiness 

action for an unsafe condition that exists in a product, the FAA evaluates the 

information provided by the exporting CAA about the unsafe condition to determine 

whether the condition is likely to exist or develop on another product of the same type 

design. The exporting CAA should provide the FAA the following information: 

(1) Make, model, and serial numbers of the affected product; 

(2) Description of the unsafe condition, reasons for the mandatory action, 

and its impact on the affected aircraft and its continued operation; 

(3) Description of the cause of the unsafe condition (e.g., stress, 

corrosion, fatigue, design problem, quality control, suspected unapproved part); 

(4) The means by which the unsafe condition was detected and, if 

resulting from in-service experience, the number of occurrences; 

(5) Corrective actions and corresponding compliance times, with a list of 

the relevant manufacturer’s service information, including reference number, revision 

number and date; 

(6) The number of aircraft operating in the U.S. (important to the FAA) vs. 

the number of aircraft worldwide needing corrective action; 

(7) A statement on the availability of parts; and 

(8) An estimate of the number of labor hours and the cost of parts required 

for the corrective actions. 

b. When an exporting CAA does not issue a mandatory continuing 

airworthiness action, but the FAA determines that one may be necessary, the 

exporting CAA should facilitate the manufacturer’s providing sufficient information, 

including service bulletins, to the FAA in a timely manner for use in evaluating the need 

for an AD. 

c. Continued airworthiness information should be sent to the FAA’s 

Delegation & Airworthiness Programs Branch, AIR-140, P.O. Box 26460, Oklahoma 

City, Oklahoma, 73125. 

42 
11/17/04 AC 21-23B 

5-4. DESIGN CHANGES.

a. Following the type certification of an aircraft, it frequently becomes 

necessary to revise data on the aircraft type design. Major changes to a type design 

not great enough to require an application for a new TC, sought by the TC holder, may 

be issued as amendments to the type certificate issued under 14 CFR 21.29, or 

otherwise approved by the FAA. A certification procedure similar to that described in 

Chapter 2 is conducted and adjusted for the magnitude and complexity of the design 

change. The FAA retains the right to determine whether the proposed change is 

substantial enough to require a new type certificate for the changed type design. 

b. Major changes to a type certificated design (for aircraft, aircraft engines, and 

propellers) which do not require an application for a new type certificate may also be 

approved through the issuance of a U.S. STC. Minor changes made by the type 

certificate holder are considered approved by the FAA upon approval by the exporting 

CAA under its normal procedures. 

c. Each voluntary change in the type design of an aircraft or engine that may 

increase fuel venting or exhaust emissions is an “emissions change” as specified in 

14 CFR 21.93, and requires further demonstration of compliance with 14 CFR part 34. 

Similarly, each voluntary change in the type design of an aircraft that may increase the 

noise levels of that aircraft is an “acoustical change,” requiring demonstration of 

compliance with 14 CFR part 36. 

d. Changes described in service bulletins, structural repair manuals, 

supplemental inspection documents, etc., with a CAA approval statement are 

accepted by the FAA and can be considered to be FAA-approved only under bilateral 

agreements. Such approval pertains to the aircraft type design only, and further FAA 

evaluation of installation or operational implications may be necessary. 

5-5. APPROVAL OF DESIGN DATA USED TO SUPPORT REPAIRS. Repair data 

used to support minor repairs must be acceptable to the Administrator. Repair data 

used to support major repairs must be approved by the Administrator or conform to the 

provisions of a bilateral agreement. The FAA may accept design data to support repairs 

when approved by the CAA under the conditions included in a BASA IPA. 

43 (and 44) 

11/17/04 AC 21-23B 

Appendix 1 

APPENDIX 1. AIRCRAFT CERTIFICATION SERVICE ORGANIZATIONAL CHART 

Director, AIR-1 

Deputy Director, AIR-2

International Policy Office, 

AIR-40 

Special Assistants, 

AIR-3 & AIR-4 

Engine & 

Propeller 

Directorate 

ANE-100 

Rotorcraft 

Directorate 

ASW-100 

Planning & 

Program 

Management

Division 

AIR-500 

Engineering 

Division 

AIR-100 

Production 

& 

Airworthiness 

Division 

AIR-200 

Small 

Airplane 

Directorate 

ACE-100 

Transport 

Airplane 

Directorate

ANM-100 

Brussels Singapore

= Located outside of Washington Headquarters 

1 (and 2) 

11/17/04 AC 21-23B 

Appendix 2 

APPENDIX 2. ACCOUNTABLE FAADIRECTORATES 

Engine and Propeller Directorate

ANE-100 

Regulatory and policy responsibility for all aircraft engines, propellers, and auxiliary 

power units. 

12 New England Executive Park 

Burlington, Massachusetts 01803 

Telephone: (781) 238-7100 

Fax: (781) 238-7199 

Bilateral Countries Assigned to ANE: Belgium, Canada, Japan, Singapore, Taiwan, and 

United Kingdom

Rotorcraft Directorate

ASW-100 

Regulatory and policy responsibility for normal and transport category rotorcraft. 

2601 Meacham Blvd. 

Fort Worth, TX 76137-4298 

Telephone: (817) 222-5100 

Fax: (817) 222-5959 

Bilateral Countries Assigned to ASW: Indonesia, Italy, and South Africa 

Small Airplane Directorate

ACE-100 

Regulatory and policy responsibility for: 

1. Normal, utility, and acrobatic category airplanes weighing less than 

12,500 pounds and having passenger configurations of 9 seats or fewer; 

2. Commuter category airplanes weighing 19,000 pounds or less, with 

passenger configurations of 19 seats or fewer; and 

3. Primary category aircraft, gliders, airships, and hot air balloons. 

DOT Building 

901 Locust, Room 301 

Kansas City, MO 64106-2641 

Telephone: (816) 329-4100 

Fax: (816) 329-4106 

Bilateral Countries Assigned to ACE: Austria, Argentina, Australia, Czech Republic, 

Germany, Malaysia, New Zealand, Poland, Romania, Russia, and Switzerland 

 1 
AC 21-23B 11/17/04 

Appendix 2 

APPENDIX 2. ACCOUNTABLE FAADIRECTORATES (Continued) 

Transport Airplane Directorate

ANM-100 

Regulatory and policy responsibility for all transport category airplanes. 

1601 Lind Avenue, SW 

Renton, WA 98055-4056 

Telephone: (425) 227-2104 

Fax: (425) 227-1100 

Bilateral Countries Assigned to ANM: Brazil, China, Denmark, Finland, France, Israel, 

Netherlands, Norway, Spain, and Sweden 

NOTE: For countries not listed above, contact the International 

Policy Office, AIR-40.

2 
11/17/04 AC 21-23B 

Appendix 3 

 Page 1 

APPENDIX 3. BILATERAL AGREEMENTS RELATED TO AIRWORTHINESS 

(AS OF SEPTEMBER 30, 2004) 

COUNTRY AGREEMENT TYPE APPLICATION/SCOPE OF 

U.S. ACCEPTANCE 

1 Argentina • BAA 

• Schedule of Implementation 

Procedures 

All aeronautical products, 

including components 

2 Australia • BAA All aeronautical products 

and certain components 

3 Austria • BAA All aeronautical products 

4 Belgium • BAA All aeronautical products 

and certain components 

5 Brazil • BAA (replaced) 

• Brazil Bilateral Aviation 

Safety Agreement – 

Executive Agreement 

• Implementation Procedures 

for Airworthiness 

All aeronautical products 

and certain components. 

Also recognizes 

Supplemental Type 

Certificate and 

maintenance. 

6 Canada • BASA Executive Agreement 

• Implementation Procedures 

for Airworthiness 

All aeronautical products, 

including components 

7 China • BAA 

Schedule of Implementation 

Procedures 

Applies to fixed-wing 

aircraft not exceeding 

12,500 lbs., commuter 

category airplanes up to 

19 passengers with a 

maximum certificated takeoff weight of 19,000 lbs. or 

less, and TSO appliances 

8 Czech Republic • BAA 

• Operating Procedures 

All aeronautical products 

9 Denmark • BAA All aeronautical products 

and certain components 

10 Finland • BAA Applies to gliders and 

aircraft appliances 

11 France • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

Applies to all aeronautical 

products and certain 

components. Also 

recognizes STC’s on 

French products. 
AC 21-23B 11/17/04 

Appendix 3 

APPENDIX 3. BILATERAL AGREEMENTS RELATED TO AIRWORTHINESS 

(Continued) 

(AS OF SEPTEMBER 30, 2004) 

2 

 COUNTRY AGREEMENT TYPE APPLICATION/SCOPE OF 

U.S. ACCEPTANCE 

12 Germany • BAA (replaced) 

• BASA Executive Agreement 

Implementation Procedures 

for Airworthiness 

(Revision 1) 

Applies to all aeronautical 

products and certain 

components. Also 

recognizes Supplemental 

Type Certificates on U.S. 

and German products. 

13 Indonesia • BAA 

• Schedule of Implementation 

Procedures 

Applies to production 

oversight in Indonesia 

under licensing 

agreements with U.S. 

manufacturers 

14 Israel • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement—Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

(Revision 1) 

All aeronautical products, 

appliances, and 

components. Also 

recognizes STC’s on U.S. 

and Israeli airplanes. 

15 Italy • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement-Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

All aeronautical products 

and certain components. 

Also recognizes STC’s on 

Italian products. 

16 Japan • BAA All aeronautical products 

and certain components 

17 Malaysia • Bilateral Aviation Safety 

Agreement-Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

(Revision 1) 

Technical Standard Order 

appliances and small 

airplanes up to 

9 passengers with a 

maximum certificated takeoff weight of 12,500 lbs. 

18 Netherlands • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement- Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

Aircraft products and 

certain components. Also 

recognizes STC’s on Dutch 

products. 
11/17/04 AC 21-23B 

Appendix 3 

APPENDIX 3. BILATERAL AGREEMENTS RELATED TO AIRWORTHINESS 

(Continued) 

(AS OF SEPTEMBER 30, 2004) 

3 

 COUNTRY AGREEMENT TYPE APPLICATION/SCOPE OF 

U.S. ACCEPTANCE 

19 New Zealand • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

Fixed-wing airplane not 

exceeding12,500 lbs., 

certain components, and 

Technical Standard Order 

appliances. Also 

recognizes STCs on New 

Zealand products. 

20 Norway • BAA (including Agreement) All categories of civil 

aircraft and appliances 

21 Poland • BAA (including 

Amendments) 

• Annex to the BAA 

(Amendments incorporated) 

Certain components; 

gliders; piston engines of 

1500 horse power or less; 

associated propellers; 

helicopters; turbine 

engines; fixed-wing aircraft 

not exceeding 12,500 lbs.; 

and commuter category 

airplanes up to 

19 passengers with a 

maximum certified take-off 

weight of 19,000 lbs. or 

less. 

22 Romania • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement- Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

Gliders and very light 

airplanes. Recognizes 

STCs on Romanian 

products. 

23 Russia • Bilateral Aviation Safety 

Agreement—Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

All metal airplanes up to 

9 passengers with a 

maximum certified take off 

weight of 12,500 lbs with 

FAA-certified engines, 

propellers, and avionics; 

cargo transport category 

airplanes with FAA certified 

engines, propellers, and 

avionics; and approved 

metallic materials. 
AC 21-23B 11/17/04 

Appendix 3 

APPENDIX 3. BILATERAL AGREEMENTS RELATED TO AIRWORTHINESS 

(Continued) 

(AS OF SEPTEMBER 30, 2004) 

4 

 COUNTRY AGREEMENT TYPE APPLICATION/SCOPE OF 

U.S. ACCEPTANCE 

24 Singapore • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement—Executive 

Agreement 

• Implementation Procedure 

for Airworthiness 

Technical Standard Order 

appliances 

25 South Africa • BAA (including Amendment) All categories of civil 

aircraft 

26 Spain • BAA (including Amendment) All categories of civil 

aircraft and appliances 

27 Sweden • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement—Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

All aeronautical products 

and certain components. 

Also recognizes STC’s on 

Swedish products. 

28 Switzerland • BAA (including Amendment) All aeronautical products 

and certain components 

29 United Kingdom • BAA (replaced) 

• Bilateral Aviation Safety 

Agreement—Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

All aeronautical products 

and certain components. 

Also recognizes STC’s on 

U.K. products. 

Other Agreements 

American 

Institute of 

Taiwan & The 

Taipei 

Economic and 

Cultural 

Representative 

Office 

• Bilateral Aviation Safety 

Agreement—Executive 

Agreement 

• Implementation Procedures 

for Airworthiness 

Technical Standard Order 

appliances 
11/17/04 AC 21-23B 

Appendix 4 

APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT 

UNDER BILATERAL AGREEMENTS 

(AS OF SEPTEMBER 30, 2004) 

Conformity

Inspection 

Third Country 

Provisions 

Maintenance 

Current 

Agreement 

Date(s) 

See Reference 

Notes Number 

BILATERAL 

COUNTRIES 

(Revised 2004) 

Aircraft 

New Replacement/Modification 

Parts For Exported Aircraft 

Aircraft Engines

New Replacement/Modification Parts 

for Exported Engines 

Propellers 

New Replacement/Modification Parts 

for Exported Propellers 

Appliances 

New Replacement/Modification Parts 

for Exported Appliances 

Materials 

Parts 

Subassemblies 

Argentina X X X X X X X X X X X 1991 2 

Australia X X X X X X X X X X X X 1975 1, 2, 3 

Austria X X X X X X 1959

Belgium X X X X X X X X X X X X 1973 1, 2 

Brazil X X X X X X X X X X X X 2004 1, 2,4 

Canada X X X X X X X X X X X X X 1984

2000 

1, 2, 5 

China X X X X X X 1995 2, 6 

Czech Republic X X X X X X X X 1970

Denmark X X X X X X X X X X X X 1982 2 

Finland X X X X 1974 7 

France X X X X X X X X X X X X X 2001 1, 2, 8 

Germany X X X X X X X X X X X X X 2002 1, 2, 9 

Indonesia 1992 10 

Israel X X X X X X X X X X X 2003 11 

Italy X X X X X X X X X X X X 2002 1, 2,12 

Japan X X X X X X X X X X X X 1977 1, 2 

Malaysia X X X X X X 2002 2,13 

Netherlands X X X X X X X X X X X X 2002 1, 2,14 

New Zealand X X X X X X X 2003 2, 15 

Norway X X X X 1978

Poland X X X X X X X X X X X X 1976,

1980 

2, 9 

Romania X X 2002 17 

Russia X X X X X 1998 2, 18 

Singapore X X X X X X 2004 1, 2, 19 

South Africa X X X X X X X X X X X 1955,

1984 

2 

Spain X X X X 1978

Sweden X X X X X X X X X X X X 2002 1, 2 

Switzerland X X X X X X X X X X X 1977 2 

United Kingdom X X X X X X X X X X X X 2002 1, 2, 20 

 Page 1 
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Appendix 4 

APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT 

UNDER BILATERAL AGREEMENTS (Continued) 

(AS OF SEPTEMBER 30, 2004) 

Other Agreements 

 

Taiwan X X X X X 2003 2 

EXPLANATION OF NOTES

1. These bilateral agreements contain a third-country provision that provides for 

import/export certification of products by the CAA of a country other than the country of 

manufacture. In these instances, the exporting country must certify that the products conform 

to the design covered by the certificate or approval of the importing country (which would be 

other than country of manufacture) and that the products are in proper state of airworthiness. 

This provision only applies when all three countries (i.e., manufacturing, importing, and 

exporting countries) have similar agreements for the reciprocal acceptance of such 

certifications covering the same class of products. The specific text of the applicable bilateral 

agreements should be consulted for any limitations. 

2. The U.S. has bilateral agreements with these countries which provide for the reciprocal 

acceptance of conformity inspections (certificates of conformity) for components (i.e., 

materials, parts, and subassemblies) produced within the limits of each particular bilateral, 

provided that: 

a. An agreement exists between the manufacturers in the importing and exporting 

countries; 

b. The component is of such complexity that a determination of conformity cannot 

readily be made by the manufacturer in the importing country; 

c. The airworthiness authorities of the importing country have notified the 

airworthiness authorities of the exporting country of the applicable design, test, and quality 

control requirements; and 

d. The authority of the exporting country is willing to undertake the conformity 

inspection task. 

3. The U.S./Australian BAA contains a two-party country provision, which provides for: 

a. Reciprocal certification whereby Australia can issue an export certificate for a 

U.S.-manufactured product located in that country which is to be exported to the U.S. 

b. Conversely, the U.S. can issue an export certificate for an Australian-manufactured 

product which is located in the U.S. and which is to be exported to Australia. 

2 
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Appendix 4 

APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT 

UNDER BILATERAL AGREEMENTS (Continued) 

(AS OF SEPTEMBER 30, 2004) 

c. Such certifications will state that the product conforms to the importing country's 

type design and is in a proper state of airworthiness. 

4. The U.S.- Brazil BASA IPA, signed on March 30, 2004, limits U.S. acceptance of 

Brazilian products to airplanes and appliances, but also provides for U.S. acceptance of 

STCs on Brazilian airplanes. 

5. The U.S./Canada BASA IPA in October 2000, includes reciprocal acceptance of all 

aeronautical products, including restricted category aircraft, replacement parts, and STC’s. 

These Implementation Procedures replace the Schedule of Implementation Procedures of 

1988, with the exception of chapter 4, Maintenance, Alteration or Modification of Aeronautical 

Products, which remains in effect until Maintenance Implementation Procedures are 

concluded. 

6. The Schedule of Implementation Procedures for the U.S./China BAA provides for 

U.S. acceptance of certain Chinese TSO appliances, fixed-wing aircraft not exceeding 12,500 

lbs., and commuter category airplanes up to 19 passengers with a maximum certificated 

take-off weight of 19,000 lbs. 

7. The U.S./Finland BAA is limited to acceptance of glider aircraft and appliances from 

each country. Although this bilateral agreement contains a provision for including appliances 

and replacement or modification parts therefore, by mutual consent of both countries’ aviation 

authorities, no appliances nor replacement/modification parts have been included to date. 

8. Maintenance Implementation Procedures were concluded with France in 1999 for 

reciprocal acceptance of repair station certifications (contact AFS-300). 

9. Maintenance Implementation Procedures were concluded with Germany in 1997 for 

reciprocal acceptance of repair station certifications (contact AFS-300.) On June 2, 2002, the 

FAA and LBA signed Revision 1 of the U.S.-Germany BASA IPA (the original IPA was 

concluded in August 1999). This revision allows for U.S. acceptance of German STCs on 

U.S. and German products, as well as some Airbus models. 

10. The Schedule of Implementation Procedures for the U.S./Indonesia BAA is limited, when 

exporting aeronautical products from Indonesia to the U.S., to the production approval and 

airworthiness certification or approval of civil aeronautical products for which the Indonesian 

manufacturer holds the manufacturing rights to a U.S. type certificate under a licensing 

agreement with a U.S. manufacturer, or with a manufacturer in another state with which the 

U.S. has an agreement for the reciprocal acceptance of type design certifications. 

3 
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Appendix 4 

APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT 

UNDER BILATERAL AGREEMENTS (Continued) 

(AS OF SEPTEMBER 30, 2004) 

11. On December 19, 2002, the U.S. and Israel concluded Revision 1 to the U.S.-Israeli 

BASA IPA. Revision 1 expands U.S. acceptance of Israeli STCs to include certain Israeli 

STCs on U.S. state of design airplanes. 

12. On June 4, 2002, the U.S. and Italy concluded a BASA IPA that includes provisions for 

U.S. acceptance of STCs on Italian products. 

13. The US/Malaysia BASA IPA provides for U.S. acceptance of Malaysian TSO appliances 

and small metal composite airplanes of up to 9 passengers with a maximum certificated takeoff weight of 12,500 lbs. 

14. The U.S.-Netherlands BASA IPA concluded on June 3, 2002, allows for U.S. 

acceptance of STCs on Dutch airplanes. 

15. The U.S./New Zealand BASA IPA, concluded on April 1, 2003, limits U.S. acceptance of 

New Zealand products to fixed-wing aircraft constructed in New Zealand not exceeding a 

maximum weight of 12,500 pounds; appliances, and their modifications and repair parts; 

16. The U.S./Poland BAA is limited to: 

a. Products, which may be exported from Poland to U.S. (or U.S. possession): 

(1) Civil gliders and replacement/modification parts therefore designed and 

produced in Poland; 

(2) Piston engines of 1,000 h.p. or less with associated propellers and accessories 

and replacement/modification parts therefore produced in Poland; 

*(3) Small fixed-wing aircraft of 12,500 pounds of less and replacement/modification 

parts therefore; 

*(4) Helicopters with associated accessories and replacement/ modification parts 

therefore; 

*(5) Turbine engines and replacement/modification parts therefore; and 

(6) Components and appliances for U.S.-manufactured products of the types 

specified in subparagraphs (1-5) above. 

*NOTE: Refer to U.S./Poland BAA for applicable design constraints. 

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Appendix 4 

APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT 

UNDER BILATERAL AGREEMENTS (Continued) 

(AS OF SEPTEMBER 30, 2004) 

b. Products, which may be exported from the U.S. to Poland: 

(1) U.S.-designed and produced aircraft, engines, propellers, components and 

appliances; and replacement/modification parts therefore; and 

(2) U.S.-produced components and appliances for Polish-manufactured products; 

and replacement and spare parts therefore. 

17. The U.S. and Romania concluded a BASA IPA on September 24, 2002. The BASA IPA 

is limited to U.S. acceptance of gliders, very light airplanes, and STCs on Romanian 

products. 

18. The U.S./Russia Implementation Procedures for Airworthiness limit U.S. acceptance to 

Russian: 

a. New and used, metal aircraft having up to 9 passengers and a maximum certificated 

take-off weight of 12,500 lbs. or less, 

b. New and used transport category aircraft (cargo configuration only) with FAAcertificated engines, propellers, and avionics, approved for Category I and Category II 

instrument approach procedures; and 

c. Metallic materials. 

Aircraft eligible for import to the U.S. must have been designed to the applicable Russian 

aviation regulations (AP’s). Aircraft built to earlier Soviet regulations are not covered under 

this agreement. 

19. The U.S./Singapore BASA IPA is limited to: 

a. Export from Singapore to the U.S.: 

(1) New TSO appliances that meet the performance standards of a U.S. Technical 

Standard Order under an FAA letter of TSO Design Approval; and their replacement parts 

b. Export from the U.S. to Singapore: 

(1) All products listed in the summary chart (page 1 of this appendix); and 

(2) Note 1 of this document (third country provision) applies to all products listed in 

the summary chart, exported from the U.S. to Singapore. 

5 
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Appendix 4 

APPENDIX 4. SUMMARY OF PRODUCTS ELIGIBLE FOR U.S. IMPORT 

UNDER BILATERAL AGREEMENTS (Continued) 

(AS OF SEPTEMBER 30, 2004) 

20. The U.S. and United Kingdom concluded a BASA IPA on May 23, 2002. The BASA IPA 

allows U.S. acceptance of U.K. STCs on British products. 

6