For the past thirty years, Lectromec has been a leader in the area of aerospace wire testing and evaluation. In order to provide aerospace professionals with information to increase their knowledge of this complex topic, we began creating educational materials. Accordingly, Lectromec has published almost two-hundred articles, distributes a monthly newsletter, has a podcast, and maintains a library of whitepapers. Because many aerospace professionals prefer communication in a more visual format, we are now providing free video resources.
We have assembled a collection of videos that look at aircraft wiring systems from many angles. Many of the videos show the impact of age, liquids, metal shavings, and even bullets on an aircraft’s Electrical Wire Interconnection Systems (EWIS). The videos also include time-lapse and high-speed photography.
Below are the videos, along with a short description of each video.
EWIS – Aerospace Wire Testing and Combat Vulnerability
When we think of aircraft wire testing, what usually comes to mind is abrasion resistance, heat shock, and other concepts that are generally considered when we look at the “airworthiness” of aircraft wires. This vintage video was recorded in the mid-1980s , and takes a look at wire survivability in a combat situation. It shows what happens when bullets hit aircraft wiring systems and the dangers of resetting circuit breakers. It is among the first videos that were created documenting the potential hazards of electrical arcing.
Wet Arc Track Resistance Testing for Aerospace Wiring
Chafing and rough maintenance can produce abrasion on aircraft wiring. Combined with moisture this can produce an arcing event. This short time-lapse video shows what happens when this dangerous combination occurs and is a good example of Wet Arc Track Resistance Testing. Essentially, a saline solution is dropped on intentionally damaged wires.
A Brief Review of MIL-HDBK-525
In an attempt to reinforce the information provided in MIL-HDBK-525, Lectromec put together a series of articles explaining it. These articles have proven to be some of the most popular blogs Lectromec has written. If you would prefer a video “assist” in understanding the handbook, take a look at this video. It is a terrific breakdown of the seven enumerated tasks of MIL-HDBK-525, including 1. Data Analysis, 2. Maintenance Data, 3. Inspection, 4. Laboratory evaluation, 5. EWIS risk assessment, 6. Mitigation, and 7. Reassessment.
EWIS – Electrical Wire Risk Assessment – Part One
After decades in the aerospace wire testing business, Lectromec has developed a software tool that helps facilitate the EWIS certification resulting from the FAA regulations. This is the first of a two part series explaining the software tool. The video focuses on regulation 25.1709 and discusses the means by which the EWIS Risk Assessment Tool (EWIS RAT) is able to lead to certification.
EWIS – Electrical Wire Risk Assessment – Part Two
This is the second part of the two part series explaining the Lectromec software tool that facilitates compliance with the Electrical Wire Interconnect Systems (EWIS) regulations needed to obtain FAA certification. This video details some of the reports that the EWIS Risk Assessment Tool (RAT) can provide. These include information on wire bundles, collocation, and a Failure Modes and Effects Analysis. It not only analyzes physical wire failures, but also the functional failure impact. In addition, it offers mitigation suggestions.
Aerospace Wire Arc Plume Filmed in High-Speed
Many aerospace professionals who are involved in maintenance, repair, and operations have seen the results of aircraft wire arcing. The nearby equipment damaged during wire system failures is normally called “collateral” damage.
Seeing an aircraft wire arc plume “in the wild” is a challenging endeavor (and one most people try to avoid). It can occur so quickly that the human eye can miss it. Lectromec reenacted a wire failure and recorded it with a high-speed camera. From the perspective of an airplane wiring engineer, this is three minutes of riveting action with ionized gas.
Aircraft Wire Arc Resistance Testing
Lectromec has been involved in airplane wire arc resistance testing for decades. This vintage video is originally from the late 1990s and was put together at the request of the National Transportation Safety Board. Technicians took wire insulation from a Boeing 747 and showed what can happen if subjected to liquids. A plane such as a 747 can have a wide range of liquids that can accidentally come in contact with wiring. Examples of liquids include cleaners, lavatory water, spilled beverages, and even condensation. The test in this video shows nicks in the insulation and the impact of moisture. The damaged wire represents environmental aging or trauma to the aerospace electrical system.
Aircraft Wire and Cable Developments
The real title of this is “What’s hot and what’s not in aerospace wire and cable.” However, aircraft wiring engineers have an aversion to anything that is “hot,” except coffee. As a result, we have titled this video “Aerospace Wire and Cable Developments.” This video is a short summary of remarks made by Lectromec’s president Michael Traskos at a recent trade conference in China. He delves into the future for aerospace wire and cable, wire system assessment and degradation, and other topics. Also included are new aerospace wire and cable requirements, certification, and trends.
“Once every five days in the United States, an aircraft is diverted because of fire/smoke caused by a wire system failure.” Michael Traskos