View Latest Blog Entries
Close
Categories
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 insertion loss 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 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

Electrical arcing of aircraft wire is hazardous even over separation

Arcing Conference & Report

Research shows hydraulic line can be punctured without direct contact with arcing wire

Recent research conducted by Lectromec confirmed the harmful effects of electrical arcing of aircraft wire events even in the presence of positive separation between the arcing source and the arcing target.

Laboratory tests using hydraulic lines as arcing targets showed that, even if an electrical arcing event fails to rupture a pressurized line directly, the event could cause a cascading effect that may puncture the line after the arcing has stopped.

A number of variables contribute to the size and the duration of electrical arcing events, as well as the damage caused by the events. The primary focus of this particular research was the impact of arc duration and separation distance on the damage caused by electrical arcing events. The research was part of a larger study by Lectromec on the relationship between arc damage and energy-environment configurations.

Arcing Event
Even with a 1.0 inch separation distance, this hydraulic line ruptured due to a nearby arcing event
Scale 1mm x 1mm
Tested in Lectromec’s lab

To the right is the result from one of the tests where the arcing stopped prior to the development of the rupture in the center. In this test, a 2AWG wires were set to arc for 0.2 seconds with a 1.0 inch separation between the wire and an aluminum tube. The tube was filled with pressurized hydraulic fluid.

The pitting on the tube indicates that multiple sites were damaged by the arcing event. In addition, the event caused a drastic and sudden shift in temperature for the aluminum tube, which, in turn, resulted in a localized and temporary weakening of the tube’s structural integrity. Combined with the pressure from the hydraulic fluid contained within, the two factors caused the rupture.

If you are interested in electrical arcing, here is an article on EWIS failure and the Process of Electrical Arcing.

Anatomy of an Electrical Event

An electrical arcing event starts when there is a dielectric breakdown that creates a conductive path between a wire and either a ground, e.g., hydraulic and fuel lines, or another wire. This can occur if there are cracks in the insulation or the wire has been chafing against a grounded surface.

An electrical arcing event generates a plume of hot, ionized gas. As the arcing continues, the arc plume quickly develops and expands. If it comes into contact with nearby objects, the plume can transfer both heat and electrical energy to the objects, making them susceptible to arcing damage even at a distance.

Electrical Arcing
UV filtered photo of the electrical arc enveloping the target tube

The image to the left was captured during an electrical arc test conducted by Lectromec. The bright, explosive portion is the arc plume generated by the arcing event. Tests such as this one allow researchers to better evaluate the arc plume’s size and direction under various energy-environment configurations, and study the correlation between configuration and actual damage.

Over the years, Lectromec has been continuously and diligently researching into the energy-environment configurations necessary in order for an arcing event to cause a hydraulic/fuel line rupture from a distance.

As demonstrated by this recent research, the effects of arcing events can be very challenging to accurately predict without an in-depth understanding of the subject matter.

Lectromec is currently in development of a robust and accurate computer-aided, arc impact prediction framework to facilitate the acquisition of such understanding for a broad range of energy-environment configurations.

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.