25.1707: EWIS System Separation Requirements Assessment White Paper
This is a 22-page summary that covers everything from damage assessment to compliance. You will learn about heavy current cables, grounding, power separation, and control cable separation. You can get resources for learning about arc damage simulations as well. The is a valuable resource for system designers as well as aerospace maintenance professionals. The illustrations and graphs give you the ability to understand some of the complexities of wire testing.Download Paper
Press Release – Lectromec Earns ISO17025 Certification
June 23, 2015, Lectromec announced that its aerospace wire testing lab has earned the coveted ISO 17025:2005 certification. It is the first aerospace wire and cable testing lab in the world to earn this quality assurance certification.
Arc Damage Modeling Tool (ADMT) Simplifying EWIS Failure Severity Assessment
The Arc Damage Modeling Tool (ADMT) was developed by Lectromec in coordination with the FAA to predict electrical arcing damage. Electrical arcing can cause significant damage to the wire and surrounding objects affecting overall aircraft airworthiness. The ADMT facilitates determination of system reliability by accurately assessing the level of damage of an arcing event. Benefits of the ADMT include quick turnaround results (reducing the need for physical tests, which are more costly and time consuming to perform), and the ability to verify design safety and provide results needed for wire certification.
Addressing Fleet Management Needs With EWIS Risk Assessment Technologies
This document provides a brief overview of Lectromec’s process for addressing the maintenance and life extension needs of airplane fleet managers. The comprehensive process combines arc damage analysis, wire insulation degradation research, and risk assessment methodologies into a single, turnkey process. The outcome from an airplane risk assessment provides a quantitative basis for business decisions on Electrical Wire Interconnect Systems (EWIS)-related preventative actions.
Aircraft Airworthiness and Sustainment Conference 2011 – Examination of EWIS and Pressurized Hydraulic Lines
This paper reports on dry arc tests performed by Lectromec on power feeder wires with pressurized tubes set at defined distances from the arcing wires. The goal of the research was to determine the level of energy necessary to cause a rupture in the target tube. The results from the laboratory testing were used as seed data for additional modeling by the Arc Damage Modeling Tool (ADMT).
Aging Aircraft Conference 2009 – Arcing Damage at a Distance
The paper describes the progress made in the analysis and understanding of electrical arcing damage to airplane components and wiring at a distance. In recent years, there has been considerable new research performed on the effects and mitigation of electrical arcing. Much of this effort investigated direct contact damage (i.e. powered wire with exposed conductor striking a grounded component or structure). The testing and analysis discussed in this paper supplement and expand upon earlier damage-at-a-distance testing.
Aging Aircraft Conference 2008 – Arc Damage Modeling Tools Progress
This paper reports on the progress in the development of a user-friendly software tool that can model the damage resulting from an arcing event. The tool is based on both analytical and empirical data and uses the concepts of energy quantification and heat transfer. The types of damage to be modeled by the tool include: damage to the source (wire) and primary target (hydraulic line, flight control cable, structure, etc.) as well as other wires in the bundle and objects at a distance.
Aging Aircraft Conference 2007 – Development of Arc Damage Modeling Tools
This paper discusses preliminary work that lays out the plan to develop an arc damage-modeling tool. As the EWIS ages, one mode of failure that is of particular concern is the arcing failure. Because of the high level of energy that can be released in an arcing event, damage can be done to structure, components, other wires in the arcing bundle, and objects some distance away from the arc. In addition, heat generated by the arc can cause the ignition of fires. There have been many efforts to mitigate the damage done by arcing. These efforts include the introduction of new wire constructions that tend to reduce or eliminate propagation of the arc, the development of arc fault circuit protection, and the use of segregation and separation techniques.
Aging Aircraft Conference 2007 – Evaluation of Wire Harnesses Recently Removed from F-16 Aircraft
Lectromec, in conjunction with InterConnect Wiring, performed an evaluation of the 35 Nomex®-covered wire harnesses that were recently removed from F-16 airplane as part of a rewire program. The wire type was Mil-W-81381, which uses polyimide insulation. The purpose of the evaluation was to determine the level of wire deterioration present in the harness. Two types of testing were performed on these harnesses: a laboratory DelTest™, a test able to locate breaches in the insulation of wires without removing the Nomex®, and an Inherent Viscosity Test that can be directly related to the elongation at break. Using these results, coupled with the aircraft EWIS data, a risk assessment was performed. The hazards posed by the aging wire were evaluated and it was determined that they accounted for risk to critical systems and possible physical damage due to electrical arcing.
Aging Aircraft Conference 2006 – Evaluation of Risk on Orbiter
In April 2004, the NASA Engineering and Safety Center (NESC) was commissioned by NASA’s Chief Safety and Mission Assurance (S&MA) Officer to review and render a technical opinion on the probability of a catastrophic failure related to the following scenario. The Space Shuttle Program (SSP) recognized a zero-fault-tolerant design related to an inadvertent firing of the primary reaction control system (RCS) jets on the Orbiter during mated operations with the International Space Station (ISS). It was determined that an un-commanded firing of an RCS jet could cause serious damage or loss of both the SSP Orbiter and the ISS. The following report summarizes the work that was sponsored by the NESC as part of their assessment of the Orbiter’s inadvertent firing of an RCS thruster while attached to the ISS.