View Latest Blog Entries
Testing & Assessment Certification Aging Wires & Systems Standard & Regulation Management Conference & Report Maintenance & Sustainment Protection & Prevention Research Arcing Miscellaneous
Popular Tags
Visual Inspection MIL-HDBK MIL-HDBK-525 AS50881 FAR High Voltage FAR 25.1707 Electromagnetic Interference (EMI) Maintenance Wire System Arcing Damage AS4373
All Tags in Alphabetical Order
25.1701 25.1703 Accelerated Aging ADMT Aging Systems Aircraft Power System Aircraft Service Life Extension Program (SLEP) arc damage Arc Fault (AF) Arc Fault Circuit Breaker (AFCB) Arc Track Resistance Arcing Arcing Damage AS22759 AS22759/87 AS4373 AS4373 Method 704 AS50881 AS5692 AS6019 AS83519 AS85485 AS85485 Wire Standard ASTM D150 ASTM F2799 ATSRAC Attenuation Automated Wire Testing System (AWTS) batteries Bent Pin Analysis Best of Lectromec Best Practice bonding Cable cable testing Carbon Nanotube (CNT) Certification Chafing Chemical Testing Circuit Breaker circuit design Circuit Protection Coaxial cable cold bend comparative analysis Compliance Component Selection Condition Based Maintenance Conductor conductors conduit Connector connectors contacts Corona Corrosion Corrosion Preventing Compound (CPC) Cracking D-sub data analysis data cables degradat Degradation Delamination Derating diagnostic dielectric constant Distributed Power System DO-160 dynamic cut through Electrical Aircraft Electrical Component Electrical Testing Electromagnetic Interference (EMI) Electromagnetic Vulnerability (EMV) EMC EMF EN3197 EN3475 EN6059 End of Service Life End of Year Energy Storage engines Environmental Environmental Cycling ethernet EWIS Component EWIS Design EWIS Failure EWIS Thermal Management EZAP FAA AC 25.27 FAA AC 25.981-1C Failure Database Failure Modes and Effects Analysis (FMEA) FAQs FAR FAR 25.1703 FAR 25.1707 FAR 25.1709 fault tree Fixturing Flammability fleet reliability Flex Testing fluid exposure Forced Hydrolysis fuel system fuel tank ignition functional testing Fundamental Articles Future Tech Green Taxiing Grounding Harness Design Hazard Analysis health monitoring heat shrink tubing high current high Frequency high speed data cable High Voltage History Hot Stamping Humidity Variation ICAs IEC60172 IEEE Instructions for Continued Airworthiness Insulation insulation resistance IPC-D-620 ISO 17025 Certified Lab Kapton Laser Marking life limited parts life projection Lightning Maintenance Maintenance costs Mandrel measurement Mechanical Testing MECSIP MIL-C-38999 MIL-C-85485 MIL-DTL-17 MIL-DTL-3885G MIL-DTL-38999 MIL-E-25499 MIL-HDBK MIL-HDBK-1646 MIL-HDBK-217 MIL-HDBK-454 MIL-HDBK-516 MIL-HDBK-522 MIL-HDBK-525 MIL-HDBK-683 MIL-STD-1560 MIL-STD-1798 MIL-STD-464 MIL-T-7928 MIL-T-81490 MIL-W-22759/87 MIL-W-5088 Military 5088 modeling MS3320 NASA NEMA27500 No Fault Found off gassing Outgassing Overheating of Wire Harness Parallel Arcing part selection Performance physical hazard assessment Physical Testing polyimdie Polyimide-PTFE Power over Ethernet Power systems predictive maintenance Presentation Probability of Failure Product Quality Radiation Red Plague Corrosion Reduction of Hazardous Substances (RoHS) regulations relays Reliability Research Resistance Rewiring Project Risk Assessment SAE Secondary Harness Protection Separation Requirements Series Arcing Service Life Extension Severe Wind and Moisture-Prone (SWAMP) Severity of Failure Shield Shielding signal cable silver plated wire smoke Solid State Circuit Breaker Space Certified Wires Splice standards stored energy supportability Sustainment Temperature Rating Temperature Variation Test methods Test Pricing Testing Thermal Circuit Breaker Thermal Endurance Thermal Index Thermal Shock Thermal Testing Tin plated conductors Troubleshooting TWA800 UAVs USAF verification Visual Inspection voltage white paper whitelisting Wire Ampacity Wire Certification Wire Comparison wire damage wire failure wire performance wire properties Wire System wire testing Wire Verification wiring components work unit code

Fall 2017 SAE Wire and Cable Meeting Update

Standard & Regulation

Every six months, the SAE wire system installation and wire/cable subcommittees come together to advance the state of the industry. This year, the Fall meeting was held in sunny Temecula, California. The following are some of the noteworthy items from this meeting.

High Voltage Endurance

The 8D task group on the evaluation of high voltage degradation of wire insulations provided an update on the work performed over the last six months. Past articles have discussed the reason for this task group and importance to the aerospace community. At the meeting, data was presented from several organizations, including Lectromec, that participated in the high-voltage endurance round robin testing. The testing involved long-term high-voltage exposure to two AS22759 wire constructions: light-weight XL-ETFE and composite wire constructions. A review of the results found a high level of consistency between the individual test lab results. As predicted, the data gathered was above the Corona inception voltage for the wire constructions.

Past results have suggested a high-voltage endurance inflection point at the corona inception voltage. High-voltage exposure above this value results in rapid degradation of the insulation. Voltages below this threshold show a much longer life. It is anticipated that additional data below the corona inception voltage will be gathered on similar samples and will be presented to the committee at the spring meeting.


A discussion topic for the last several years has been on the source and prevention of red plague. A test method added into the AS4373 last revision was the low fluorine off-gassing test. This test method was designed to support the low fluorine off-gassing wire specifications 22759/51-54. For those specifications, the off-gassing threshold was set to be less than 20 ppm. This threshold was set because it had been determined that PTFE had a fluorine off-gassing below this threshold and there have been no reported red plague issues with PTFE. The question posed at the committee meeting was if off-gassing threshold could be increased?

The reason for this question is twofold: first, when a wire insulation’s properties are improved in one area, it is common that this results in a performance reduction in other areas. For those manufacturers seeking to achieve the 20 ppm threshold, design choices must be made that can have an impact on the wire insulation’s melting temperature, mechanical strength, and/or the electrical performance. Second, by raising the bar, this can allow for more manufacturers to supply product, and in doing so, create competition between brands.

M39029 cross section contact
When crimping wires into contacts, the proper crimp tool setting and contacts make all of the difference.

High Strength Wire Termination

The Daniels Manufacturing Company presented data on work performed to determine the performance of high-strength wire terminations. There have been questions on the performance of wire contacts crimped on high-strength copper alloys. The uncertainty exists if standard contacts (M39029 contacts) provide the proper level of compression on high-strength copper alloy conductors. Given that the high-strength copper alloy requires more force to deform, the research also investigated if different crimping strengths were necessary and if there was a measurable impact on the final tensile strength. Although the work is still ongoing, a great deal of data was presented. Some of the important results include resolving some questions about fast cycling of crimping tools (whether there is a noticeable performance degradation if a contact is rapidly crimped versus a slow, methodical crimp). The research suggests no appreciable difference between the two techniques.

Next Meeting

Further information on each of these task groups is anticipated at the next meeting for the 8A/8D committees in Chicago, Illinois (April 2018).

Michael Traskos

Michael Traskos

President, Lectromec

Michael has been involved in wire degradation and failure assessments for more than a decade. He has worked on dozens of projects assessing the reliability and qualification of EWIS components. Michael is an FAA DER with a delegated authority covering EWIS certification and the chairman of the SAE AE-8A EWIS installation committee.