Significance and Use
4.1 Design—The design procedures defined in this practice are intended to provide acceptable guidance in the original design of electrical systems.
4.2 Alteration—The alteration procedures defined in this practice are intended to provide acceptable guidance for modification of general aviation aircraft. Design of any modification shall follow the practices and processes defined in the design sections of this practice.
4.3 Certification—Certification guidance provided in this practice is intended to provide generally accepted procedures and processes for certification of original and modified electrical systems and equipment. Requirements for certification shall be coordinated with the applicable National Aeronautics Association/Civil Aeronautics Administration (NAA/CAA) regulatory agency.
Scope
1.1 Definition—This practice defines acceptable practices and processes for the design, alteration, and certification of electric systems and installations in general aviation aircraft. This practice does not change or create any additional regulatory requirements nor does it authorize changes in or permit deviations from existing regulatory requirements.
1.2 Applicability—The guidance provided in this practice is directed to air carriers, air operators, design approval holders, Supplemental Type Certificate (STC) holders, maintenance providers, repair stations, and anyone performing field approval modifications or repairs.
1.3 Protections and Cautions—This practice provides guidance for developing actions and cautionary statements to be added to maintenance instructions for the protection of wire and wire configurations. Maintenance personnel will use these enhanced procedures to minimize contamination and accidental damage to electrical wiring interconnection system (EWIS) while working on aircraft.
1.4 “Protect and Clean As You Go” Philosophy—This philosophy is applied to aircraft wiring through inclusion in operators’ maintenance and training programs. This philosophy stresses the importance of protective measures when working on or around wire bundles and connectors. It stresses how important it is to protect EWIS during structural repairs, STC installations, or other alterations by making sure that metal shavings, debris, and contamination resulting from such work are removed.
1.5 This practice includes the following sections:
Title
Section
Wire Selection
5
General
5.1
Aircraft Wire Materials
5.2
Table of Acceptable Wires
5.3
Severe Wind and Moisture Problems (SWAMP)
5.4
Grounding and Bonding
5.5
Electrical Wire Chart
5.6
Wire and Cable Identification
6
General
6.1
Wire and Cable Identification
6.2
Types of Markings
6.3
Sleeve and Cable Marker Selection
6.4
Placement of Identification Markings
6.5
Wiring Installation
7
General
7.1
Wire Harness Installation
7.2
Power Feeders
7.3
Service Loops
7.4
Drip Loops
7.5
Soldering
7.6
Strain Relief
7.7
Grounding and Bonding
7.8
Splicing
7.9
Fuel Tank Wiring
7.10
Corrosion Preventative Compounds (CPC)
(MIL-C-81309)
7.11
Electrical Load Considerations
8
General
8.1
Methods for Determining the Current-Carrying
Capacity of Wires
8.2
Acceptable Means of Monitoring and
Controlling the Electrical Load
8.3
Electrical System Components
9
General
9.1
Alternators
9.2
Generators
9.3
Ground Power Units
9.4
Auxiliary Power Units
9.5
Batteries
9.6
Circuit Protection Devices
9.7
Conduit
9.8
Connectors
9.9
Inverters and Power Converters
9.10
Junctions
9.11
Junction Boxes
9.12
Electronic Assemblies
9.13
Relays
9.14
Studs
9.15
Switches
9.16
Terminals and Terminal Blocks
9.17
Waveguides
9.18
Electrical System Component Installation
10
General
10.1
Alternators
10.2
Generators
10.3
Auxiliary Power Units (APUs)
10.4
Batteries
10.5
Circuit Protection Devices
10.6
Conduit
10.7
Connectors
10.8
Inverters and Power Converters
10.9
Junctions
10.10
Junction Boxes, Panels, Shields, and
Microswitch Housings
10.11
PC Board Assemblies
10.12
Relays
10.13
Studs
10.14
Switches
10.15
Terminals and Terminal Blocks
10.16
Waveguides
10.17
EMI/RFI
11
General
11.1
Grounding and Bonding
11.2
HIRF
11.3
Lightning
11.4
Alterations
12
General
12.1
Wire Substitutions
12.2
Commercial Off-the-Shelf (COTS) Components
12.3
Electrical Load Considerations
12.4
Batteries
12.5
Circuit Breakers
12.6
Junction Boxes
12.7
Relays
12.8
Switches
12.9
Wire Marking
12.10
Wire Bundle Routing
12.11
Wire Bundle Combing
12.12
Interference Tests
12.13
System Safety Assessments
12.14
Certification Processes
13
General
13.1
Certification
13.2
Alterations and Maintenance
13.3
1.6 Values—The values given in inch-pound units are to be regarded as the standard. The values in parentheses are for information only. See Appendix X2 for SI-based prefixes and powers of 10.
NOTE 1: Where SI units are required, refer to Annex 5 of ICAO.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.