Airworthiness Approval of Attitude Heading Reference System (AHRS) Equipment
This advisory circular (AC) supplements existing airworthiness approval guidance for attitude heading reference system (AHRS) articles approved under technical standard order (TSO)?C201, Attitude Heading Reference System, or later revisions. TSO-C201 includes performance standards for non-gimbaled attitude, heading, and turn and slip systems.
Guidelines for the Certification, Airworthiness, and Operational Use of Electronic Flight Bags
This joint Flight Standards Service (AFS) and Aircraft Certification Service (AIR) advisory circular (AC) contains guidance on the operational use of Electronic Flight Bags (EFBs). It is intended for all operators conducting flight operations under Title 14 of the Code of Federal Regulations (14 CFR) part 121, 125, 135, or 91 subpart F (part 91F) and part 91 subpart K (part 91K) who want to replace required paper information or utilize other select functions of an EFB. This AC sets forth an acceptable means, but not the only means, to obtain Federal Aviation Administration (FAA) authorization for the operational use of EFBs. Part 91 operators can find additional EFB information in the current edition of AC 91-78, Use of Class 1 or Class 2 Electronic Flight Bag (EFB). For guidance on the installation of EFB components, refer to the current edition of AC 20-173, Installation of Electronic Flight Bag Components.
The Certification of Aircraft Electrical and Electronic Systems for Operation in the High-intensity Radiated Fields (HIRF) Environment
a. This advisory circular (AC) will provide you with information and guidance on how to show compliance with Title 14, Code of Federal Regulations (14 CFR) 23.1308, 25.1317, 27.1317, and 29.1317, High-intensity Radiated Fields (HIRF) Protection.
b. This AC is not mandatory and does not constitute a regulation. It describes an acceptable means, but not the only means, for you to show compliance with the requirements for protection of the operation of electrical and electronic systems on an aircraft when the aircraft is exposed to an external HIRF environment. If you use the means described in this AC, you must follow it entirely to comply with this AC. The term "must" is used to indicate mandatory requirements when following the guidance in this AC. The term "should" is used when following the guidance is recommended but not required to comply with this AC.
Service Bulletins Related to Airworthiness Directives and Indicating FAA Approval on Service Documents
This advisory circular (AC) presents best practices for drafting service bulletins (SB) related to an airworthiness directive (AD). This AC also provides information and guidance on ex parté communication and alternative methods of compliance (AMOC), as well as means for avoiding overlapping and conflicting actions in SBs and maintaining airworthiness of AD-mandated design changes. This revision, AC 20-176A, includes guidance for indicating FAA approval on a service document.
Airworthiness Approval for Aircraft Weather Radar Systems
a. This advisory circular (AC) provides guidance for the initial and follow-on airworthiness approval of aircraft weather radar systems meeting the latest revision of the Technical Standard Order (TSO)-C63, Airborne Weather Radar Equipment. This AC covers aircraft weather and ground mapping pulsed radar systems, and airborne Doppler weather radar systems with forward-looking windshear, turbulence detection or weather hazard indication capability. The guidance is applicable to Title 14 of the Code of Federal Regulations, parts 23, 25, 27, and 29 aircraft. This AC does not address forward-looking windshear and/or turbulence detection capability for rotorcraft.
b. This AC is not mandatory and does not constitute a regulation. This AC describes an acceptable means, but not the only means, of accomplishing airworthiness approval for the installation of airborne weather radar equipment. However, if you use the means described in this AC, you must follow it entirely. The term "must" is used to indicate mandatory requirements when following the guidance in this AC. The terms "should" and "recommend" are used when following the guidance is recommended but not required to comply with this AC. A list of related documents can be found in Appendix B of this AC.
c. This AC provides guidance intended for new approvals. This AC is not intended to modify, change, or cancel existing equipment design or airworthiness approvals. Equipment with existing approvals can continue to be installed within the provisions of its original design and airworthiness certification.
Maintenance of Airport Visual Aid Facilities
This AC provides guidance and specifications for the Maintenance of airport Visual Aid Facilities.
Collaborative Trajectory Options Program (CTOP)
This Advisory Circular provides guidance to customers of the National Airspace System (NAS) regarding a new traffic management initiative for managing flights through a constrained area. The new traffic management initiative builds upon concepts found in Ground Delay Programs (GDPs), Airspace Flow Programs (AFPs; AC 90-102A) and required reroutes. The new initiative is called the Collaborative Trajectory Options Program or CTOP. The CTOP is one of many new traffic management initiatives being developed within Collaborative Air Traffic Management Technologies (CATMT) as we progress toward the Next-Generation Air Transportation System (NextGen).
Approval of Propulsion Fuels, Additives, and Lubricating Oils
This advisory circular (AC) provides guidance applicable to adding fuels and oils as engine, aircraft, or auxiliary power unit (APU) operating limitations. It also provides guidance on fuel and lubricating oil specifications and standards, and on propulsion fuel and/or lubricating oil certification plans. This AC provides acceptable methods, but not the only methods, that may be used to approve aircraft, engines, or APUs to operate with specified propulsion fuels and lubricating oils.
Design and Installation Details for Airport Visual Aids
This AC provides guidance and recommendations about the installation of airport visual aids.
Standards for Specifying Construction of Airports
The standards contained in this AC relate to materials and methods used for the construction of airports. Items covered in this AC include general provisions, earthwork, flexible base courses, rigid base courses, flexible surface courses, rigid pavement, fencing, drainage, turfing, and lighting installation.
Access related Pay Reduction Spreadsheets on our Airport Design Software page.
Standardized Method of Reporting Airport Pavement Strength - PCN
This AC provides guidance for using the standardized International Civil Aviation Organization (ICAO) method, called the Aircraft Classification Number – Pavement Classification Number (ACN-PCN) method, to report airport runway, taxiway, and apron pavement strength. Includes instructions for using the COMFAA program to calculate ACN values to determine PCN.
Also provides guidance for reporting changes to airport data that is generally published on Federal Aviation Administration (FAA) Form 5010, Airport Master Record, particularly those data elements associated with Gross Weight (Data Elements 35 through 38) and Pavement Classification Number (Data Element 39).
Access COMFAA and related Support Spreadsheet on our Airport Design Software page.