This advisory circular describes an acceptable means for showing compliance with the requirements of § 25.621, Casting factors, of Title 14, Code of Federal Regulations part 25. Section 25.621 outlines the factors, tests, and inspections that must be applied to castings used in structural applications.
Architectural, Engineering, and Planning Consultant Services for Airport Grant Projects
This AC provides guidance for airport sponsors in the selection and engagement of architectural, engineering, and planning consultants. It also discusses services that normally would be included in an airport grant project, types of contracts for these services, contract format and provisions, and guidelines for determining the reasonableness of consultant fees. Please see the Principal Changes paragraph for a list of major changes from the last version of this AC.
Airport Snow and Ice Control Equipment
This advisory circular provides guidance to assist airport operators in the procurement of snow and ice control equipment for airport use.
Flight Standards Service Schedule of Charges Outside the United States
This advisory circular (AC) transmits an updated schedule of charges for services of Federal Aviation Administration (FAA) Flight Standards Service (AFS) aviation safety inspectors (ASI) outside the United States. Rulemaking action to Title 14 of the Code of Federal Regulations (14 CFR) part 187, Docket No. 27809 and Notice 94-24, Fees for Certification Services and Approvals Performed Outside the United States, established the methodology for determining these charges. The rulemaking established that the FAA would publish these fees in an AC.
Oxidation, Hot Corrosion, Thermal Fatigue, and Erosion Characteristics Testing to Support 14 CFR, Part 33, § 33.15, Compliancefor Turbine Engines
This advisory circular (AC) describes an acceptable method, but not the only method, to support certain comparative assessment compliance findings to Title 14 of the Code of Federal Regulations (14 CFR) part 33, § 33.15, Materials, for turbine engine projects. Comparative assessment of certain data is often necessary to show the required functional and durability equivalencies between engine combustor and turbine section parts from different design or manufacturing processes, e.g., parts manufacturer approvals (PMA) versus type design parts. These equivalencies relate to oxidation, hot corrosion, and thermal fatigue and erosion characteristics in the engine environment. This data is necessary to support overall FAA design approval of turbine engine and auxiliary power unit (APU) parts approved under PMA, type certificate (TC) design change, supplemental type certificate (STC), or repair or alteration authority.
Additional Pilot Program for Phase I Flight Test
This advisory circular (AC) provides information and guidance on the Additional Pilot Program (APP) for flight testing experimental aircraft. The APP was developed to improve safety by enhancing Builder/Owner Pilot (BP) skills and mitigate risks associated with Phase I flight testing of aircraft built from commercially produced kits through the use of a qualified additional pilot and powerplant testing. The APP is an optional program which provides another pathway to conducting Phase I flight testing. The traditional option for a pilot to test their aircraft solo during Phase I is not covered or affected by this AC, and remains an option for those who choose to do so in accordance with their aircraft’s operating limitations.
Mitigating the Risks of a Runway Overrun Upon Landing (Include Chg 1)
This advisory circular (AC) provides ways for pilots and airplane operators to identify, understand, and mitigate risks associated with runway overruns during the landing phase of flight. It also provides operators with detailed information that operators may use to develop company standard operating procedures (SOP) to mitigate those risks.
Airfield Pavement Surface Evaluation and Rating Manuals
This AC provides limited guidance on understanding and rating the surface condition of flexible (asphalt) and rigid (concrete) airfield pavements. Appendices A and B of this AC include the Asphalt and Concrete Airfield Pavement Surface Evaluation and Rating Manuals (PASER Manuals). The FAA recommends the information and procedures contained in the manuals for use by airport staff and consultants, directly or in combination with additional testing and data collection, only when it is not possible to complete a more detailed pavement condition index (PCI) survey as part of a more comprehensive pavement maintenance management program.
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.
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.
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.
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).
Maintenance of Airport Visual Aid Facilities
This AC provides guidance and specifications for the Maintenance of airport Visual Aid Facilities.
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.
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.
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.
Guidance Material For 14 CFR §33.28, Engine Control Systems
This advisory circular (AC) provides guidance and describes acceptable methods, butnot the only methods, for demonstrating compliance with the engine control systems requirements of § 33.28 of Title 14 of the Code of Federal Regulations (14 CFR part 33) at amendment level 3326.
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.
Use of Cockpit Displays of Digital Weather and Aeronautical Information
This advisory circular (AC) provides guidance to flightcrew members and other airmen on the use of data link to access Flight Information Services (FIS). This AC addresses both the Federal Aviation Administration (FAA) FIS Broadcast (FIS-B) provided through the Automatic Dependent Surveillance – Broadcast (ADS-B) Universal Access Transceiver (UAT) network and non-FAA FIS systems provided through commercial data link services.
a. Flight Information Services (FIS). FIS is a service that provides Meteorological Information (METI) and Aeronautical Information (AI) to enhance pilot awareness of weather and/or airspace constraints while providing information for decision support tools and improving safety. METI and AI data link services enable flightcrews to support the Next Generation Air Transportation System (NextGen) concepts of information sharing and provide airmen with a common operating picture necessary to support the evolving global Air Traffic Management (ATM) concepts.
b. Advantages of FIS METI and AI. FIS of METI and AI can augment pilot voice communications with Flight Service Stations (FSS), other air traffic control (ATC) facilities, airline dispatch centers, flight following facilities or other Operation Control Centers (OCC), typically referred to as System Operations Control (SOC). In addition, Internet connectivity provides the capability for Baseline Synchronization Services (BSS) to be utilized to update the aircraft’s navigational and other databases prior to flight.
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.
Airworthiness Approval of Positioning and Navigation Systems (Including Change 2)
This revision adds minor clarifications and new guidance material based on issues and questions since revision ‘C’ was published. There are several new changes such as: equipment capability versus installed limitations; clarifying database configuration versus equipment capability; adding step-down fixes to navigation databases; a new appendix for demonstrating radius to fix (RF) leg capability; and, including required navigation performance (RNP) prediction guidance for RNP authorization required approach (RNP AR APCH).
Application for Parts Manufacturer Approval Via Tests and Computations or Identicality
a. This advisory circular (AC) updates the Federal Aviation Administration’s (FAA) guidance to applicants for parts manufacturer approval (PMA) of articles via tests and computations or identicality without a license agreement. This AC cites regulations in Title 14, Code of Federal Regulations (14 CFR) part 21, Subpart K that became effective April 16, 2011. In addition, this AC provides a convenient application and compliance checklist, adds a certifying statement of compliance, provides guidance for assessing an article’s impact on safety and describes how the FAA approves replacement parts for technical standard order (TSO) articles. This AC does not apply to the articles that are listed in 14 CFR 21.9(a)(1) through (6).
b. This AC refers to parts and components as articles per 14 CFR 21.1. This section defines an article as a material, part, component, process or appliance. These items may include sealants, modified standard parts, brake assemblies, etc. that are in a product’s type design. Please note PMA is not for base materials, processes or inspection procedures.
c. This AC is not mandatory and does not constitute a regulation. This AC describes an acceptable means, but not the only means, to comply with 14 CFR Part 21, Subpart K. If you chose to use any of these best practices, we expect you to follow it completely. Adherence to the guidance for each applicable facet will show that an article’s design complies with the airworthiness requirements of its eligible products. Also consult other ACs when you need guidance on product specific requirements for showing compliance. For example, AC 33-8 has guidance for Parts Manufacturer Approval of Turbine Engine and Auxiliary Power Unit Parts under Test and Computation.
Airworthiness Approval of Traffic Alert and Collision Avoidance Systems (TCAS II), Versions 7.0 & 7.1 and Associated Mode S Transponders
This advisory circular (AC) provides applicants with guidance for obtaining an airworthiness approval for traffic alert collision avoidance systems II (TCAS II). It also provides guidance for certification of a stand-alone Mode S transponder system. This AC includes the TCAS II versions 7.0 and 7.1 (TSO-C119b and TSO-C119c respectively) along with the latest iteration, which is version 7.1, containing hybrid surveillance functionality as defined by TSO-C119d.
Chemical Oxygen Generator Security Standards
This advisory circular (AC) provides guidance for an acceptable means of showing compliance with the requirements of Title 14, Code of Federal Regulations(14 CFR) 25.795(d), Chemical oxygen generators. Section 25.795(d) requires each chemical oxygen generator (COG) or its installation to be designed so it meets one of several criteria. The means of compliance described in this document provides guidance to supplement the engineering and operational judgment that must form the basis of any compliance findings relative to a COG installed on an airplane.