AC 21-99 Download: A Guide to Aircraft Wiring and Bonding
If you are involved in aircraft maintenance, you may have heard of AC 21-99. This is an advisory circular issued by the Australian Civil Aviation Safety Authority (CASA) that provides guidance material for maintenance of aircraft electrical systems and bonding of aircraft. In this article, we will explain what AC 21-99 is, why it is important for aircraft maintenance, how to download it, and what are the main topics covered by it.
ac 21-99 download
What is AC 21-99?
AC 21-99 stands for Advisory Circular 21-99. It is a document that provides advice and guidance to illustrate a means, but not necessarily the only means, of complying with the Civil Aviation Safety Regulations (CASR) Part 21. It also explains certain regulatory requirements by providing informative, interpretative, and explanatory material. When an AC is referred to in a Note below a regulation, the AC remains as guidance material. ACs should always be read in conjunction with the referenced regulations.
The purpose and scope of AC 21-99
The purpose of AC 21-99 is to provide guidance material for maintenance of aircraft electrical systems and bonding of aircraft. It covers topics such as wire and cable selection, identification, preparation, repair, soldering, lacing, tying, sealing, connectors, bonding, grounding, busbars, junction boxes, protective devices, terminal boards, thermocouple wire soldering and installation, aged aircraft wiring inspection and maintenance.
The scope of AC 21-99 applies to all ADF aircraft. It does not apply to civil registered aircraft operated by ADF or foreign military registered aircraft operated in Australia.
The status and revision of AC 21-99
This is the first issue of AC 21-99 to be written on aircraft wiring and bonding procedures. It was issued in November 2005. It may be revised or cancelled in the future depending on the changes in regulations or technology.
Why is AC 21-99 important for aircraft maintenance?
AC 21-99 is important for aircraft maintenance because it provides best practices and standards for ensuring the safety and reliability of aircraft electrical systems and bonding. By following the guidelines in AC 21-99, you can:
ac 21-99 aircraft wiring and bonding pdf
ac 21-99(0) advisory circular
ac 21-99 annex g
ac 21-99 revision 2
ac 21-99 chapter 1
ac 21-99 section 2
ac 21-99 part 21
ac 21-99 manual of standards
ac 21-99 permissible unserviceabilities
ac 21-99 solderless terminations and splices
ac 21-99 electrical wire installation
ac 21-99 wire and cable identification
ac 21-99 soldering techniques
ac 21-99 lacing and tying wiring
ac 21-99 repairing wire and cable
ac 21-99 preparing wire and cable
ac 21-99 civil aviation safety authority
ac 21-99 australia
ac 21-99 november 2005
ac 21-99 version 2.1
ac 21-99 aircraft wiring and bonding (PDF, 18.88 MB)
ac 21-99 technical standard order program
ac 21-99 certification and airworthiness requirements for aircraft and parts
ac 21-99 type certificates and type acceptance certificates
ac 21-99 supplemental type certificates and production certificates
ac 21-99 certificates of airworthiness and export airworthiness approvals
ac 21-99 approval of aircraft engines, propellers, and certain materials and parts
ac 21-99 airworthiness certification standards in parts 22 to 35 of CASR
ac 21.099 subpart H light sport aircraft (LSA)
ac 21.099 subpart J approved design organisations (ADOs)
how to download ac 21.099 pdf file online
where to find ac 21.099 document for free download
what is the purpose of ac 21.099 advisory circular
how to apply the guidelines of ac 21.099 in aircraft wiring and bonding
what are the benefits of using ac 21.099 for aircraft maintenance and repair
who is affected by the rules of part 21 of CASR as explained in ac 21.099
what are the differences between the revisions of ac 21.099
how to access the legislative instruments related to part 21 of CASR and ac 21.099
what are the best practices for soldering, lacing, and tying wiring as per ac 21.099
how to identify and repair permissible unserviceabilities as per ac 21.099
The benefits of following AC 21-99 guidelines
Reduce the risk of electrical fires, shorts, arcs, sparks, corrosion, interference, or failures that could compromise the performance or integrity of the aircraft or its systems.
Improve the efficiency and durability of the electrical components and wiring by using appropriate materials, methods, tools, and techniques.
Enhance the quality and consistency of the electrical work by using proper identification, marking, documentation, inspection, testing, and verification procedures.
Comply with the regulatory requirements and expectations of CASR Part 21 and other relevant authorities.
The risks of ignoring AC 21-99 recommendationsIgnoring the recommendations of AC 21-99 could result in:
Increased risk of electrical hazards, accidents, incidents, or injuries that could endanger the lives of the crew, passengers, or ground personnel.
Decreased performance, efficiency, or reliability of the electrical systems or components that could affect the operation or mission of the aircraft.
Increased cost, time, or complexity of the electrical maintenance, repair, or replacement due to poor quality, inconsistency, or non-compliance of the electrical work.
Potential legal, regulatory, or contractual liabilities or penalties for failing to meet the standards or requirements of CASR Part 21 or other relevant authorities.
How to download AC 21-99?
If you want to download AC 21-99, you have two options:
The official source of AC 21-99
The official source of AC 21-99 is the CASA website. You can access the document by following these steps:
Go to
Click on "Publications" in the top menu bar.
Click on "Advisory Circulars" in the left sidebar.
Click on "AC 21 - Certification and Airworthiness Requirements for Aircraft and Parts" in the list of categories.
Scroll down to find "AC 21-99 Aircraft Wiring and Bonding" and click on the link to download the PDF file.
The alternative sources of AC 21-99
If you cannot access the CASA website or prefer a different format, you can also find AC 21-99 from other sources. However, you should always check the validity and currency of the document before using it. Some of the alternative sources are:
: This is a link to the FAA Advisory Circular AC 43.13-1B - Acceptable Methods, Techniques, and Practices - Aircraft Inspection and Repair. This document contains similar information and guidance as AC 21-99 but for US aircraft. You can download it as a PDF file.
: This is a link to a Scribd document that contains a scanned copy of AC 21-99. You can view it online or download it as a PDF file.
: This is a link to a SlideShare presentation that contains a summary and overview of AC 21-99. You can view it online or download it as a PPT file.
What are the main topics covered by AC 21-99?
AC 21-99 covers a wide range of topics related to aircraft wiring and bonding. Here are some of the main topics covered by AC 21-99:
Wire and cable selection, identification, preparation, and repair
This topic covers how to select, identify, prepare, and repair wires and cables for aircraft electrical systems. It includes information on wire and cable types, sizes, ratings, markings, colors, insulation materials, shielding materials, splicing methods, crimping methods, stripping methods, cleaning methods, testing methods, and repair methods.
Soldering, lacing, tying, and sealing techniques
This topic covers how to solder, lace, tie, and seal wires and cables for aircraft electrical systems. It includes information on soldering tools, materials, techniques, standards, inspection criteria; lacing tools, materials, techniques; tying tools, materials, techniques; sealing tools, materials, techniques.
Connector types, installation, and sealing
This topic covers how to select, install, and seal connectors for aircraft electrical systems. It includes information on connector types, sizes, ratings, materials, configurations, terminations; installation tools, methods, procedures; sealing tools, methods, procedures.
Bonding and grounding principles and practices
This topic covers how to bond and ground aircraft electrical systems. It includes information on bonding and grounding principles, purposes, functions; bonding and grounding types, methods, locations; bonding and grounding tools, materials, techniques, standards, inspection criteria.
Busbars, junction boxes, protective devices, and terminal boards installation
This topic covers how to install busbars, junction boxes, protective devices, and terminal boards for aircraft electrical systems. It includes information on busbar types, sizes, ratings, materials, configurations; junction box types, sizes, ratings, materials, configurations; protective device types, sizes, ratings, materials, functions; terminal board types, sizes, ratings, materials, configurations; installation tools, methods, procedures.
Thermocouple wire soldering and installation
This topic covers how to solder and install thermocouple wires for aircraft electrical systems. It includes information on thermocouple wire types, sizes, ratings, materials, colors; soldering tools, materials, techniques; installation tools, methods, procedures.
Aged aircraft wiring inspection and maintenance
This topic covers how to inspect and maintain aged aircraft wiring for aircraft electrical systems. It includes information on aged aircraft wiring problems, causes, effects; inspection tools, methods, procedures; maintenance tools, methods, procedures.
Conclusion
AC 21-99 is a valuable resource for aircraft maintenance personnel who deal with aircraft electrical systems and bonding. It provides guidance material for complying with the CASR Part 21 and ensuring the safety and reliability of the electrical components and wiring. By downloading and following AC 21-99, you can improve your knowledge and skills in selecting, identifying, preparing, repairing, soldering, lacing, tying, sealing, connecting, bonding, grounding, installing, inspecting, and maintaining aircraft electrical systems and bonding.
Summary of the main points
In this article, we have covered the following main points:
What is AC 21-99 and what is its purpose and scope?
Why is AC 21-99 important for aircraft maintenance and what are the benefits and risks of following or ignoring it?
How to download AC 21-99 from the official or alternative sources?
What are the main topics covered by AC 21-99 and what are the key information and guidance provided by each topic?
Call to action for the readers
If you want to learn more about AC 21-99 or other related topics, you can visit the following websites:
: The official website of CASA where you can find more advisory circulars, regulations, publications, and resources on aviation safety.
: A website that provides a comprehensive guide to aircraft wiring for homebuilt aircraft.
: An article that discusses the basics of aircraft wiring and bonding.
We hope you have found this article helpful and informative. If you have any questions or feedback, please feel free to contact us or leave a comment below. Thank you for reading!
Frequently Asked Questions
What is the difference between bonding and grounding?
Bonding is the process of connecting two or more conductive parts together to ensure electrical continuity and conductivity. Grounding is the process of connecting a conductive part to the earth or another reference point to provide a path for excess current or static discharge.
What are some of the common problems with aged aircraft wiring?
Some of the common problems with aged aircraft wiring are: insulation degradation, wire chafing, wire cracking, wire corrosion, wire contamination, wire overheating, wire arcing, wire shorting, wire open circuiting.
What are some of the tools and materials required for soldering wires?
Some of the tools and materials required for soldering wires are: soldering iron or gun, soldering tip or nozzle, solder wire or paste, flux or rosin core solder, heat shrink tubing or tape, wire stripper or cutter, wire brush or cleaner, solder sucker or wick.
What are some of the types of connectors used for aircraft electrical systems?
Some of the types of connectors used for aircraft electrical systems are: pin-and-socket connectors, blade-and-receptacle connectors, bayonet connectors, threaded connectors, coaxial connectors.
How often should aircraft wiring be inspected and maintained?
The frequency of inspection and maintenance of aircraft wiring depends on several factors, such as the age, type, condition, usage, and environment of the aircraft. However, as a general rule, AC 21-99 recommends that aircraft wiring should be inspected at least once every 12 months or 100 flight hours, whichever comes first. Additionally, aircraft wiring should be maintained whenever there is any sign of damage, deterioration, or malfunction. 44f88ac181
コメント