CHAPTER 3
AIRWORTHINESS STANDARDS
TRANSPORT CATEGORY ROTORCRAFT
MISCELLANEOUS GUIDANCE (MG) AC 27 MG 23 AUTOMATIC FLIGHT GUIDANCE AND CONTROL SYSTEMS (AFGCS) INSTALLATION IN PART 27 ROTORCRAFT.
a. Purpose.
(1) This guidance recognizes the following Radio Technical Commission for Aeronautics (RTCA) documents as acceptable for showing compliance with regulatory requirements for the installation of automatic flight control guidance and control systems (AFGCS).
(i) RTCA Document DO-325, Minimum Operational Performance Standards (MOPS) for Automatic Flight Guidance and Control Systems and Equipment, issued December 8, 2010.
(ii) RTCA Document DO-336, Guidance for Certification of Installed Automatic Flight Guidance and Control Systems (AFGCS) for Part 27/29 Rotorcraft, issued March 21, 2012.
(2) RTCA Document DO-325 contains the minimum operational performance standards (MOPS) for AFGCS equipment, included by reference in TSO-C198. DO-336 provides guidance on obtaining installation approval of AFGCS in rotorcraft. It invokes parts of DO-325 as performance standards applicable for installation of AFGCS equipment in rotorcraft. It provides guidance on conducting a safety assessment.
Lastly, DO-336 lists the regulations applicable to an AFGCS installation and acceptable methods of compliance to those regulations.
(3) This guidance is not mandatory. It describes an acceptable means, but not the only means, for showing compliance with applicable 14 CFR regulations. Following this guidance alone does not guarantee acceptance by the FAA. Depending on circumstances, we may require additional substantiation or design changes as a basis for finding compliance.
b. Background. Technical standard order (TSO) TSO-C198, Automatic Flight Guidance and Control system (AFGCS) Equipment, replaced TSO-C9c, Automatic Pilots, and TSO-C52b, Flight Director Equipment. TSO-C198 identifies a new comprehensive minimum operation performance standard (MOPS) under RTCA Document DO-325 and qualifications for software and airborne electronic hardware.
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AC 27-1B, Chg 6 7/25/2014 Note: The intent was to highlight to the system designer that early coordination with an aircraft original equipment manufacturer (OEM) is important to minimize the compliance requirements at the time of installation, and that even without an OEM, the guidance is relevant when installing the system.
c. Guidance for the use of RTCA Documents DO-325 and DO-336.
(1) RTCA Document DO-325 identifies the typical functions of an AFGCS. We recommend that AFGCS equipment manufacturers obtain technical standard order authorization (TSOA) for TSO-C198 to minimize compliance showings that would be required at installation approval stage. There should be a declaration of any non-TSO functions in the TSOA application so there can be an appropriate evaluation and acceptance of the software and hardware qualification data related to those functions. If AFGCS equipment does not have TSOA for TSO-C198, the applicant for installation approval would have to show compliance with the DO-325 MOPS, as appropriate to functions provided, and conduct the necessary software and hardware qualifications defined in DO-178 and DO-254 guidance documents.
(2) RTCA Document DO-336 has two primary focus items: to highlight the requirements for a proper safety assessment (Chapter 8) and to highlight the compliance demonstration (Chapter 9). Each of these should be discussed with the appropriate Aircraft Certification Office (ACO) very early in the program and included in the certification plan.
d. References.
(1) 14 CFR Regulations (available at http://rgl.faa.gov/):
Section Title
27.671 General. (Control Systems)
27.672 Stability augmentation, automatic, and power-operated systems.
27.1309 Equipment, systems, and installations.
27.1329 Automatic pilot system.
27.1335 Flight director systems.
Appendix B to Part 27 Airworthiness Criteria for Helicopter Instrument Flight
(2) TSOs (available at http://rgl.faa.gov/):
TSO Title TSO-C198 Automatic Flight Guidance and Control system (AFGCS) Equipment Page MG 23 - 2
(3) ACs (refer to current version; available at http://rgl.faa.gov/):
AC Title 20-115 Radio Technical Commission for Aeronautic, Inc., Document RTCA/DO-178B 20-138 Airworthiness Approval of Positioning and Navigation Systems 20-152 RTCA, Inc., Document RTCA/DO-254, Design Assurance Guidance for Airborne Electronic Hardware.
21-50 Installation of TSOA Articles and LODA Appliances 27-1, Section Control Systems - General.
27.671 Section 27-1, Stability Augmentation, Automatic, and Power-Operated Systems.
27.672 27-1, Section Equipment, Systems, and Installations.
27.1309 27-1, Section Automatic Pilot System.
27.1329 27-1, Section Flight Director Systems.
27.1335
(4) Industry standards (refer to the current version; RTCA documents are available at www.rtca.org and SAE International documents are available at www.sae.org):
Document Title RTCA/ Software Considerations in Airborne Systems and DO-178 Equipment Certification RTCA/ Design Assurance Guidance for Airborne Electronic DO-254 Hardware RTCA/ Minimum Operational Performance Standards (MOPS) for DO-325 Automatic Flight Guidance and Control Systems and Equipment, issued December 8, 2010.
RTCA Guidance for Certification of Installed Automatic Flight DO-336 Guidance and Control Systems (AFGCS) for Part 27/29 Rotorcraft, issued March 21, 2012.
SAE, International Guidelines for Development of Civil Aircraft and Systems ARP 4754 SAE, Guidelines and Methods for Conducting the Safety International Assessment Process on Civil Airborne Systems and ARP 4761 Equipment Page MG 23 - 3
AC 27-1B APPENDIX А
INSTRUCTIONS FOR CONTINUED AIRWORTHINESS Instructions for Continued Airworthiness (ICA) are required by Federal Aviation Regulations (FAR)/Joint Airworthiness Regulations (JAR) § 27.1529. Appendix A to FAR/JAR Part 27 specifies the requirements for Instructions for Continued Airworthiness. The following 70 pages for this AC 27-1B, Appendix A, provide a template for the ICA. This ICA Template was prepared to assist applicants in preparing an ICA for their type design change to rotorcraft.
The guidance is intended for applicants that are required to comply with FAR/JAR § 27.1529 to prepare Instructions for Continued Airworthiness acceptable to FAA/AUTHORITY.
The ICA Template contains requirements of Appendix A to FAR/JAR Part 27, identified by bold type. The bold type requirements are to be included in the applicant Instructions for Continued Airworthiness as applicable to the applicant's type design change. Items in regular type are not required by FAR/JAR; however, these items are an aviation industry standard and are found in most current Instructions for Continued Airworthiness. The underlined words and sentences are to emphasize the information. It is recommended the applicant include those in their ICA for standardization and clarity.
The ICA Template is arranged as a sample Instructions for Continued Airworthiness document and can be used as a template for the preparation of the applicant's Instructions for Continued Airworthiness. The ICA Template was prepared to cover a complete rotorcraft. The applicant for a type design change need not include all information for the appropriate type design, only the applicable information to their type design change.
Appropriate text in regular type can be copied from the ICA Template. Text in italics and the appendices are for instructions and are not to be copied.
The ICA Template is formatted using the Airline Transport Association (ATA) Chapter numbering system. The ATA Chapter format is not required; however, it is recommended. The ATA chapter numbers that are not listed in this document do not relate to ICA's and are not used in the ATA system for ICA's (Maintenance Manual). The Standard Practices chapters are broken out separately from the other listed chapters because they are not a requirement.
However, Standard Practices are an industry standard and are found in most industry Maintenance Manuals.
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AC 27-1B, Chg 1 2/12/03 AC 27-1B
APPENDIX A
INSTRUCTIONS FOR CONTINUED AIRWORTHINESS (continued) The set of parentheses in the index and chapters indicates the chapter on the ICA Template that is applicable to various ATA chapters. The set of parentheses in Figure 1 and Figure 2 is used to indicate the applicability of the item for that type design change.
Instructions for Continued Airworthiness will be reviewed and evaluated by FAA/AUTHORITY to ascertain their acceptability.
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AC27 APPENDIX A. INSTRUCTIONS FOR CONTINUED AIRWORTHINESS (MANUAL IDENTIFICATION)
INSTRUCTIONS FOR CONTINUED AIRWORTHINESS TEMPLATE (COMPANY NAME)
INSTRUCTIONS FOR CONTINUED AIRWORTHINESS
DRAWING/PHOTOGRAPH
OPTIONAL (ROTORCRAFT MAKE AND MODEL) REVISION: (DATE) Revision 4 Page i Page Apdx A - 3
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(MANUAL IDENTIFICATION)
RECORD OF REVISIONS
REVISION ISSUE DATE BY REVISION ISSUE DATE BY
NUMBER DATE INSERTED NUMBER DATE INSERTED Original 08/04/97 09/03/97 E. R. THOMAS 1 01/30/98 02/14/98 E. R. THOMAS 2 06/18/98 07/02/98 E. R. THOMAS 10/21/99 11/01/99 E. R. THOMAS 4 08/04/00 08/24/00 E. R. THOMAS REVISION: (PAGE NUMBER) Revision 4 Page iii Page Apdx A - 5
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(MANUAL IDENTIFICATION)
LIST OF EFFECTIVE PAGES LIST OF REVISIONS Revision 0 (Original Issue).. August 4, 1997 Revision 1 •January 30,1998 Revision 2 June 18,1998 Revision 3 October 21,1999 Revision 4 August 4, 2000
LIST OF EFFECTIVE PAGES Title Pages Revision No.
COVER i, ii BLANK 4 RECORD OF REVISION iii, iv BLANK 4 LIST OF EFFECTIVE PAGES v THRU vi 4 TABLE OF CONTENTS vii THRU x 4 CHAPTER 1 INTRODUCTION 01-00-00 1 THRU 8 4 CHAPTER 4 AIRWORTHINESS LIMITATION SECTION 04-00-00 1, 2 BLANK 4 CHAPTER 5 INSPECTIONS 05-00-00 1 THRU 4 4 CHAPTER 6 DIMENSION AND ACCESS 06-00-00 1, 2 BLANK CHAPTER 7 LIFTING AND SHORING 07-00-00 1, 2 BLANK 2 CHAPTER 8 LEVELING AND WEIGHING 08-00-00 1, 2 BLANK CHAPTER 9 TOWING AND TAXIING 09-00-00 1, 2 BLANK 2 CHPATER 10 PARKING AND MOORING 10-00-00 1, 2 BLANK 4 CHAPTER 11 PLACARDS AND MARKING 11-00-00 1, 2 BLANK 4 CHAPTER 12 SERVICING 12-00-00 1, 2 BLANK 2 CHAPTERS 20, 51, 60, 70, STANDARD PRACTICES ( )-00-00 1, 2 BLANK CHAPTERS 21, 22, 23, 24, 25, 26, 27, 29, 30, 31, 33, 34, 35, 36, 37, 45, 49, AIRFRAME SYSTEM ( )-00-00 52, 53, 54, 55, 56, STRUCTURES ( )-00-00 62, 63, 64, 65, 66, 67 ROTORS ( )-00-00 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, and 83 POWERPLANT ( )-00-00 1,2,3, 4, 5, 3 6, 7, 8 4 Attachment 1 PART 27 REQUIREMENTS 1, THRU 5, 6 BLANK 4 Attachment 2 INSTRUCTIONS FOR CONTINUED AIRWORTHINESS PROCEDURE INFORMATION 1 AND 2 3 Attachment 3 AT CHAPTER LISTING 1, 2 BLANK 3 Attachment 4 TYPE DESIGN CHANGE ICA RECOMMENDED PROCEDURE 1, THRU 9,10 BLANK 4 REVISION: (PAGE NUMBER) Revision 4 Page v Page Apdx A - 7
AC 27-1B, Chg 1 2/12/03 (MANUAL IDENTIFICATION)
LIST OF EFFECTIVE PAGES
a. The applicant should provide a means of identifying each page of the Instructions for Continued Airworthiness (ICA) so maintenance personnel know they have a complete and current ICA. There is no requirement for a specific format; however, there is an established standard format that has been used by industry for many years. This standard is the List of Effective Pages.
b. The applicant should list all pages, their revision number and revision date contained in the applicant's ICA on a "List of Effective Pages" page either for the complete manual or by each chapter. If individual chapter method is used, the manual should have a masteriList of Effective Pages page containing all the chapters and their revision numbers.
C. A page means a single side of a leaf within the ICA. When no text is intended for a page the following statement should be on the blank page: THIS PAGE INTENTIONALLY LEFT BLANK. In addition the intentionally left blank page should contain the manual identification, revision number and page number. If a page has not been revised from the original issue, then this will always be designated with a revision number of "O." It is a standard industry practice to list "Revision O" to indicate an original issue page. The revision number will remain the same until ICA is accepted by the FAA/AUTHORTY regardless of the number of draft changes made prior to acceptance.
d. The section that lists multiple chapters and has parentheses ( )-00-00 indicates that the information is applicable to any of those chapters; i.e., Chapters 21, 33, 52, 67, or 71 of the ATA chapter format. The chapter numbers are not sequential because those missing chapters are not applicable to rotorcraft.
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(MANUAL IDENTIFICATION
TABLE OF CONTENTS Identification Title Page CHAPTER 1 INTRODUCTION 01-00-00
1. ACCEPTABLE TO THE FAA/AUTHORITY
2. MANUALS
3. CONTENTS
4. SCOPE
5. PURPOSE
6. ARRANGEMENT
7. SUPERSEDED DOCUMENTS
8. APPLICABILITY
9. DEFINITIONS
10. ABBREVIATIONS
11.ACRONYMS
12. SYMBOLS
13. PRECAUTIONS
14. UNITS OF MEASUREMENT
15. ICA FOR EACH ENGINE
16. ICA FOR EACH ROTOR
17. ICA FOR EACH APPLIANCE REQUIRED BY THIS CHAPTER 4
18. INFORMATION ESSENTIAL TO THE CONTINUED
AIRWORTHINESS OF THE ROTORCRAFT
19. REFERENCED PUBLICATIONS
20. DISTRIBUTION
21. ROTORCRAFT FEATURES
22. CORRECTIONS TO ORIGINAL INSTRUCTIONS FOR
CONTINUED AIRWORTHINESS
23. INDICATING CHANGES TO INSTRUCTIONS FOR
CONTINUED AIRWORTHINESS CHAPTER 4 AIRWORTHINESS LIMITATIONS SECTION 04-00-00
1. AIRWORTHINESS LIMITATIONS INFORMATION
2. NO AIRWORTHINESS LIMITATIONS INFORMATION REQUIRED.
CHAPTER 5 INSPECTION REQUIREMENTS AND OVERHAUL SCHEDULE 05-00-00
1. INSPECTION REQUIREMENTS
2. COMPONENT OVERHAUL SCHEDULE
3. NO OVERHAUL REQUIRMENTS
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