View Latest Blog Entries
Testing & Assessment Certification Standard & Regulation Aging Wires & Systems Maintenance & Sustainment Management Conference & Report Protection & Prevention Research Miscellaneous Arcing
Popular Tags
Visual Inspection High Voltage AS50881 MIL-HDBK MIL-HDBK-525 FAR AS4373 Electromagnetic Interference (EMI) Maintenance FAR 25.1707 Wire System Arcing Damage
All Tags in Alphabetical Order
2021 25.1701 25.1703 abrasion AC 33.4-3 AC 43 Accelerated Aging ADMT Aging Systems AIR6808 AIR7502 Aircraft Power System aircraft safety Aircraft Service Life Extension Program (SLEP) altitude arc damage Arc Damage Modeling Tool Arc Fault (AF) Arc Fault Circuit Breaker (AFCB) Arc Track Resistance Arcing Arcing Damage AS22759 AS22759/87 AS23053 AS29606 AS4373 AS4373 Method 704 AS50881 AS5692 AS6019 AS6324 AS81824 AS83519 AS85049 AS85485 AS85485 Wire Standard ASTM B355 ASTM B470 ASTM D150 ASTM D2671 ASTM D8355 ASTM D876 ASTM F2639 ASTM F2696 ASTM F2799 ASTM F3230 ASTM F3309 ATSRAC Attenuation Automated Wire Testing System (AWTS) Automotive Avionics backshell batteries bend radius Bent Pin Analysis Best of Lectromec Best Practice bonding Cable Cable Bend cable testing Carbon Nanotube (CNT) Certification cfr 25.1717 Chafing Chemical Testing Circuit Breaker circuit design Circuit Protection cleaning clearance Coaxial cable cold bend collision comparative analysis Compliance Component Selection Condition Based Maintenance Conductor Conductor Testing conductors conduit Connector Connector rating connector selection connector testing connectors contacts Corona Corrosion Corrosion Preventing Compound (CPC) corrosion prevention Cracking creepage D-sub data analysis data cables degradat Degradation Delamination Derating design safety development diagnostic Dielectric breakdown dielectric constant Dimensional Life disinfectant Distributed Power System DO-160 dry arc dynamic cut through E-CFR electric aircraft Electrical Aircraft Electrical Component Electrical Power Electrical Testing Electrified Vehicles Electromagnetic Interference (EMI) Electromagnetic Vulnerability (EMV) Electrostatic Discharge EMC EMF EN2235 EN3197 EN3475 EN6059 End of Service Life End of Year Energy Storage engines Environmental Environmental Cycling environmental stress ethernet eVTOL EWIS certification EWIS Component EWIS Design EWIS Failure EWIS sustainment EWIS Thermal Management EZAP FAA FAA AC 25.27 FAA AC 25.981-1C FAA Meeting failure conditions Failure Database Failure Modes and Effects Analysis (FMEA) FAQs FAR FAR 25.1703 FAR 25.1707 FAR 25.1709 Fault fault tree Fixturing Flammability fleet reliability Flex Testing fluid exposure Fluid Immersion Forced Hydrolysis fuel system fuel tank ignition Functional Hazard Assessment functional testing Fundamental Articles Fuse Future Tech galvanic corrosion Glycol Gold Gold plating Green Taxiing Grounding hand sanitizer handbook Harness Design harness protection hazard Hazard Analysis health monitoring heat shrink heat shrink tubing high current high Frequency high speed data cable High Voltage High Voltage Degradation HIRF History Hot Stamping Humidity Variation HV connector HV system ICAs IEC 60851 IEC60172 IEEE immersion Inspection installation installation safety Instructions for Continued Airworthiness insulating material insulating tape Insulation insulation breakdown insulation resistance insulation testing interchangeability IPC-D-620 ISO 17025 Certified Lab ISO 9000 J1673 Kapton Laser Marking life limit life limited parts Life prediction life projection Lightning lightning protection liquid nitrogen lithium battery lunar Magnet wire maintainability Maintenance Maintenance costs Mandrel mean free path measurement mechanical stress Mechanical Testing MECSIP MIL-C-38999 MIL-C-85485 MIL-DTL-17 MIL-DTL-23053E 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-1353 MIL-STD-1560 MIL-STD-1798 MIL-STD-464 MIL-T-7928 MIL-T-7928/5 MIL-T-81490 MIL-W-22759/87 MIL-W-5088 MIL–STD–5088 Military 5088 modeling moon MS3320 NASA NEMA27500 Nickel nickel plating No Fault Found OEM off gassing Outgassing Over current Overheating of Wire Harness Parallel Arcing part selection Partial Discharge partial discharge at altitude Performance physical hazard assessment Physical Testing polyamide polyimdie Polyimide-PTFE Power over Ethernet power system Power systems predictive maintenance Presentation Preventative Maintenance Program Probability of Failure Product Quality PTFE pull through Radiation Red Plague Corrosion Reduction of Hazardous Substances (RoHS) regulations relays Reliability Research Resistance Revision C Rewiring Project Risk Assessment S&T Meeting SAE SAE Committee Sanitizing Fluids Secondary Harness Protection separation Separation Requirements Series Arcing Service Life Extension Severe Wind and Moisture-Prone (SWAMP) Severity of Failure shelf life Shield Shielding Shrinkage signal cable Silver silver plated wire silver-plating skin depth skin effect Small aircraft smoke Solid State Circuit Breaker Space Certified Wires Splice standards Storage stored energy superconductor supportability Sustainment System Voltage Temperature Rating Temperature Variation Test methods Test Pricing Testing testing standard Thermal Circuit Breaker Thermal Endurance Thermal Index Thermal Runaway Thermal Shock Thermal Testing tin Tin plated conductors tin plating tin solder tin whiskering tin whiskers top 5 Transient Troubleshooting TWA800 UAVs UL94 USAF validation verification video Visual Inspection voltage voltage differential Voltage Tolerance volume resistivity vw-1 wet arc white paper whitelisting Winding wire Wire Ampacity Wire Bend Wire Certification Wire Comparison wire damage wire failure wire performance wire properties Wire System wire testing Wire Verification wiring components work unit code

Building an aircraft electrical wire testing program: Selecting tests, Part I


This article, which focuses on test selection, is a continuation of a discussion on wire selection that was started in the Determining the Right Wire for your Application article. The series could be used as a basis for understanding electrical wire testing. A quick scan of the wire tests on demonstrates that there are dozens of tests developed for assessing wires. These tests evaluate the physical, chemical, and electrical properties of the manufactured end product as well as its usability under different stresses and environmental conditions. This article will focus on Physical and Electrical tests.

Physical Tests

These tests typically focus on the insulation’s ability to withstand physical stresses to prevent a breach to the conductor. Often these tests were designed with a particular failure mode (e.g. Scrape abrasion), which represents the conditions in a swaying or vibrational environment. These tests pull, push, flex, twist, compress, and cut the wire insulation to determine wire performance.

In the case of the aerospace industry, there is a drive towards design and requirement improvement. As such, you can typically assume that the newest generation wire will perform better in many aspects than the last.

A few key tests that should be considered when selecting physical tests:

1. Scrape Abrasion

The scrape abrasion test is a good test to see how well the insulation can withstand rubbing against an edge. While this test sometimes will yield inconsistent results (particularly with wrapped insulations), the results do provide good data to make relative comparisons between sample types. Tests should be performed at ambient and elevated temperatures.

2. Notch Propagation

The notch propagation test evaluates the progression of a small notch in the insulation and the longevity of the insulation integrity. If the small notch is able to quickly breach, the conductor will typically indicate a more rigid insulation. Because this test wraps the wire on a mandrel for hundreds of cycles, the conductor is more likely to fail on small gauge wires than high quality insulations.

3. Elongation to Break

This test is performed on the insulation after the conductor has been removed. Pulled until the insulation snaps, this provides good comparative data on the insulation strength. This test should also be considered when multiple accelerated aging cycles are performed.

Electrical Tests

Electrical Wire Testing
Electrical Test Equipment for Wire Evaluation

Electrical tests analyze how a completed wire handles electrical loads. This may focus on the conductor, such as resistance measurement, on the insulation, such as insulation resistance, or a combination of the two with a ‘time to smoke’ test.

A few key tests that should be considered when selecting electrical tests:

1. Surface resistance test

In conditions with high humidity, the insulation surface conduction can be a source for leakage current. The surface resistance test evaluates the leakage current in such an environment.

2. Insulation Resistance

The insulation resistance test measures the insulation dielectric strength. If accelerated aging cycles are being performed, this is a good test to evaluate the electrical degradation of the insulation.

3. Wet or Dry Arc Track Resistance

Electrical failure can cause more damage that resetting a circuit breaker. In systems with a high cost of failure, an arc track event can damage systems, conduct electricity to other circuits, and cause significant physical damage to nearby components. This test evaluates the propensity for arc tracking. Read Lectromec’s Wet and Dry Arc Track Resistance Testing article for more information on this test.

4. Current to Smoke

The current to smoke test evaluates the electrical current level necessary to cause the wire to smoke. Most wire insulation products include chemicals that should not be inhaled; assessment of this characteristic should be considered when the application is in enclosed areas with personnel. Read Lectromec’s Electrical Tests for Aerospace Wires and Cables article for more information on electrical tests.


There is no “one size fits all” wire and there is not a single test program that is applicable to all wire types or environmental conditions. Just like any other component, selecting the right wire for the right application takes time and effort. For mission critical systems, wire system integrity is often as important as component or device integrity. Making an educated and informed decision upfront can significantly reduce maintenance issues down the line.

The next article will review the chemical and usability tests that can be performed on wires to assess their quality and properties for a particular application.

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.