SAE April 2022 Update
After two unsuccessful attempts to meet in person, the SAE AE-8A/D committee met to update standards whose progress has been slowed over the last two years. Read more
By: Michael Traskos
High Voltage Arc Tracking Requirements (Part 2)
In part 2 of this article series, we continue to discuss how arc track resistance testing as we know it must be re-evaluated as more HV systems with unique testing requirements lead the aviation industry moving forward. Read more
High Voltage Arc Tracking Requirements (Part 1)
Arc track resistance testing has been a staple of the aerospace industry for nearly 40 years. This originated from the issues raised in the 1980s with polyimide insulated wire. Since that time, test methods have evolved to assess and quantify the susceptibility of wires to carbon arc tracking and the ability to withstand electrical arcing events. Read more
EWIS High Voltage Certification
With the gradual industry implementation of high voltage EWIS systems in aviation, the demand for HV-specific safety standards is rapidly growing. High voltage OEMs currently use available industry standards, as applicable, but are still left with the task of developing and justifying their own system requirements. The SAE’s AS50881 standard, often considered the ‘go-to’ standard for OEMs, could benefit from proposed updates made to address the gaps for high voltage systems. Read more
Life-Limiting High Voltage Parts
Life-Limited EWIS parts can be useful where high voltage conditions make component degradation rates uncertain. Though accelerated aging can offer insight to the component’s condition, further observations of high-voltage systems will be needed for accurate degradation predictions. Read more
The Longevity of High Voltage Components
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. Read more
Risk Assessment and Small Aircraft Certification
The basic idea behind the F3230 is to limit the total number of assessments to those that are of particular concern for aircraft safety. This aligns with the change of part 23 aircraft the FAA has implemented for a more performance-based certification approach versus the detailed and prescriptive approach that the FAA used prior to 2016. Read more
Aerospace High Voltage Systems: Addressing the Gaps in Current Standards
The aerospace segment has been dealing with questions of high voltage systems for the last decade. Many of these questions revolve around the generation, storage, and use of this power, but what has also been a hindrance for progress is defining how the standards for the wiring system need to be updated to address these high voltage requirements. As should be done when any new technology is being applied to a field, we should first look at other fields which have undergone the implementation of similar technologies. For example, the automotive market has been using high voltage systems for quite some time and the standards committees have produced documents supporting these technologies.
In this article, we review one of these documents on high voltage directed to the automotive market and see how it lines up with the existing aerospace standards.
Read moreSkin Effect
An area of power transmission that we have not talked about in any Lectromec article thus far is the impact of skin effect. While this is an area that is well documented and understood for signal/data cables, the impacts in the area of power cables have been generally ignored. However, as power systems embrace new power technologies, skin effect starts to creep in to have a noticeable and measurable impact. In this article, we discuss what skin effect is and its impact.
Read moreIn Consideration of Backshells
The backshell of a connector is an item that perhaps does not get the attention that it should. Often the discussion of EWIS focuses on the wiring, the connectors, or managing the risk of EWIS failures, but the connector backshell is ignored. The simple connector backshell (that is anything but simple) is designed for support and protection of wires and cables physically and, in the case of signal cables, support and protect electrically too. The following is a brief introduction to backshells, their use, associated standards, and research that has been performed to determine what to look for when performing maintenance.
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