With the ramp-up of production across the entire supply chain, new vehicle concepts coming closer to being fielded, and continued research supporting the next generation of aircraft, 2022 was a big year for the aerospace industry. Lectromec was busy working on dozens of projects and performed R&D activities on:
- Development of an electrical wire harness thermal model for estimating the impact of dynamic current loads (beyond the current derating for steady-state conditions in AS50881).
- Expansion of Lectromec’s Arc Damage Modeling Tool (ADMT) to better model high voltage arcing events.
- Expanded our high voltage DC power bank for representing the next generation of high voltage power supplies. Naturally, Lectromec used it for electrical arcing tests.
- EWIS component degradation and expanding Lectromec’s existing remaining life prediction models.
- A dozen new test fixtures for unique and novel test methods.
Lastly, Lectromec has finally been able to expand our footprint. Just this month, Lectromec’s office and lab doubled in size by expanding into an adjoining suite. This will give Lectromec the much-needed room for expansion of our staff and lab capabilities.
Top 5 of 2022
The following are the top five articles of 2022.
#5 – WHICH RED PLAGUE TESTING IS RIGHT FOR MY APPLICATION?
Corrosion avoidance of silver-plated conductors is not a simple task and visual inspection will only identify the most obvious degradation.
Red plague is corrosive galvanic corrosion that occurs between the silver plating and copper core of silver-plated copper wire. This has been a known issue since at least the 1950s and has popped up dozens of times since then with issues identified during initial product inspection, at product acceptance, as well as cases where red plague corroded wires and cables resulted in multi-million dollar rewiring efforts. While there are several means to test for red plague, understanding which to apply for an application is not clear. This article helps to clear this up.
#4 THE LONGEVITY OF HIGH VOLTAGE COMPONENTS
With ‘high voltage’ becoming the new buzzword of aerospace, it is only natural that a couple of Lectromec’s top 5 articles of 2022 would be on high voltage.
One open question in the industry right now is what is the required performance of a high voltage wire/cable? Furthermore, what does a wire need to do in the high voltage system, and how does it need to perform? This article reviews some of the fundamental concepts involved and what needs to be done to show a wire is compliant with the vehicle’s requirements.
#3 – AIR7502 AND FUTURE IMPLICATIONS FOR AVIATION
Again, with the high voltage. As a starting point for understanding high voltage and how it is impacting system design, a good place to start is with AIR7502. The SAE AE-7 committee is charged with the development and upkeep of standards, specs, and requirements regarding aerospace electrical power and equipment. In 2021, the SAE AE-7 committee published AIR7502, a document detailing the committee’s agreed-upon definitions for aircraft electrical voltage levels.
#2 – ICA GUIDANCE FOR HIRF AND LIGHTNING PROTECTION
Aircraft are inherently expected to endure a wide variety of environmental challenges which include both High-Intensity Radiated Fields (HIRF) and lightning strikes. HIRF and lightning strikes similarly can produce significant EMI in aircraft EWIS, thus functions have been developed and incorporated into aircraft to prevent damage and interference from these sources. The lifespan of these protection functions is directly impacted by aircraft maintenance actions and can be improved by incorporating specific, detailed Instructions for Continued Airworthiness (ICA). Article.
#1 – EWIS HIGH VOLTAGE CERTIFICATION
It should be no surprise that an article on the certification of high voltage EWIS was at the top of the list for 2022. This article reviewed sections of the aerospace wiring system installation standard AS50881 and if there are gaps in how to support the high voltage aircraft sector. Beyond just identifying the gaps, the means to address these gaps were also proposed.
This was a topic that Lectromec presented at the 2022 FAA-Lead Science and Technology Electrical Systems and Wiring Interagency Meeting. The presentation will be posted early in 2023. Until that time, the article is available here.
Upcoming in 2023
The new year has not started, and it is gearing up for another busy year. In addition to all of the great projects the Lectromec team will be working on, you can expect to see articles on:
- Continued developments of high voltage EWIS
- A proposal on performance requirements for a high voltage wire and cable
- Qualification of new conductor alloys
- Assessment of commercial EWIS reliability, an update of Lectromec’s 2016 white paper
- And much more.
Michael Traskos
President, Lectromec
michael.traskos@lectromec.comMichael 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.