MIL-HDBK-525 overview for service life extension

August 15, 2013 Michael Traskos

The newly published Electrical Wiring Interconnect System (EWIS) Integrity Program Handbook (MIL-HDBK-525) provides a comprehensive method for assessing an aircraft’s EWIS condition for service life extension and ensuring continued airworthiness. There has not been a consistent method by which maintainers have determined the EWIS system health of their platforms, leaving each group to develop their […] Read more

In aircraft wire systems, how much slack should I give a wire?

July 27, 2013 Michael Traskos

Clearly wires shouldn’t be pulled so tight that they are under constant regular strain, but is there some guidance as to how much slack should be provided in aircraft wire systems? One source for guidance comes from the FAA in AC 25.1701. In this advisory circular, the guidance suggests that “EWIS components should have sufficient […] Read more

Minimum bend radius as applied to aircraft wire system degradation

July 26, 2013 Michael Traskos

Constant mechanical strain can and will reduce a wire’s longevity. Knowledge of minimum bend radius can reduce wire system degradation. These stresses can come from clamps that are too tight, over compressed harnesses protection sleeving, or poor routing. One method to reduce this potential mechanical strain in harness routing, is to ensure that all harnesses […] Read more

High voltage systems on aircraft

May 24, 2013 Michael Traskos

Aerospace Information Report (AIR) 6127 currently being developed by the SAE AE-7 committee provides a framework for designing high voltage subsystems utilized for More Electric Aircraft (MEA). The AIR identifies design risks, mitigation techniques, and testing methods for MEA. Electrical discharges on MEA are a potential risk that should be mitigated through careful design and […] Read more

Odd wire gauges for aircraft wiring

April 25, 2013 Michael Traskos

Have you ever wondered why only even wire gauges are produced (e.g. 8, 16, 20, etc.) for aircraft wiring? For centuries, wire manufactures have produced even wire gauges because there has been little or no demand for odd wire gauges. Further, there is a slight difference between a 22AWG and 23AWG and a 23AWG and […] Read more

Building an electrical wire testing program: Selecting tests, Part II

March 18, 2013 Michael Traskos

This article is a continuation in a series devoted to providing guidance to engineers on what should be considered when comparing different wire insulation types for a given application. It can be the basis of an electrical wire testing. Here are the previous articles: Determining the Right Wire for your Application Building a Wire Program […] Read more

Building an aircraft electrical wire testing program: Selecting tests, Part I

February 7, 2013 Michael Traskos

This article, which focuses on test selection, is a continuation of a discussion on wire selection that was started in the Determining the Right Wire for your Application article. The series could be used as a basis for understanding electrical wire testing. A quick scan of the wire tests on WireFacts.com demonstrates that there are […] Read more

Correct aircraft wire selection for your application

January 17, 2013 Michael Traskos

Wire selection for a particular application can be a time consuming process. Selection of the right wire for the particular application to maintain device reliability and prevent a potential catastrophic failure (in the case of signal quality degradation or electrical arcing for power wires) can be difficult.In the aerospace industry, this is rather simple: there […] Read more

The age of your aircraft and wire systems implications

November 15, 2012 Michael Traskos

A fleet age review of 16 American aircraft operators performed by Lectromec is shown below. This includes both regional and major airlines as well as shipping companies. The data is based on available FAA data for US registered aircraft. Percentage of Fleet in Age Range Carrier # of Aircraft Average Age 16 – 20 years […] Read more

Flammability for Aircraft Wiring

November 5, 2012 Michael Traskos

Among the multitude of new wire qualification tests is the wire flammability test for aircraft wiring. This article covers a test that is designed to assess a wire insulation’s ability to: 1) limit the burn length when exposed to a flame; 2) have no molten material drop from the sample; and 3) not ignite. Read more

By: Michael Traskos