Arc damage modeling tool and damage at a distance

July 4, 2008 Lectromec Team

The amount of damage that can be caused by electrical arcing events continues to be an important question for both new and legacy aircraft. Many factors can affect the damage done by arcing events. For example, events occurring a short distance from a power bus can have much higher currents and power than those a long distance […] Read more

Aircraft wire failure and wire component lifecycle

June 20, 2008 Lectromec Team

In the life cycle of components, including aircraft wiring and connectors that make up the interconnection harnesses, there are three phases of the component lifecycle that can be distinguished. They are a key part of understanding wire failure and make up the “bathtub curve” and they are: The observed failure rate (Blue) is a composite […] Read more

Use of aircraft “shelf wire” and aircraft wire life projection

May 26, 2008 Lectromec Team

Suppose that your customer wants to know if the wiring in the cables, harnesses, or devices that your company produced is good. What if they have questions about aircraft wire life projection. Perhaps the cable that you used was a MIL-spec wire, but had been on the shelf or in the manufacturing plant for a number […] Read more

Physical and functional EWIS issues included in Rule 25.1709

January 1, 2008 Lectromec Team

The recent set of FAA rules deal with physical and functional EWIS issues. The rules were released for the Enhanced Airworthiness Program for Airplane Systems/Fuel Tank Safety (EAPAS/FTS) places new requirements on system safety and certification of aircraft Electrical Wiring Interconnection Systems (EWIS). These new rules were effective as of December 2007. They are the culmination […] Read more

Aircraft databases that impact aircraft engineers

November 1, 2007 Lectromec Team

There are a number of aircraft databases that exist on the web that can be used to survey aircraft incidents and service problems. One of these databases may have the answer to an important question from an aircraft engineer. This Lectrogram shall provide a brief summary of several of the more robust databases relevant to aircraft […] Read more

Damage at a distance on aircraft wire systems

August 1, 2007 Lectromec Team

What is the effective distance in wire systems that electrical arcing can cause? Both lab tests and in-service incidents have shown that arcing is hot enough to cause significant damage when in direct contact with an object, but there is far less information on the damage that can be caused at a distance. Read more

XL-ETFE and ETFE for aircraft wire compared

March 1, 2007 Lectromec Team

XL-ETFE and ETFE are not the same. ETFE (or commonly referred in the industry as Tefzel®) is a well known material used in the aircraft and space industry. In fact, ETFE is a widely used material in applications as diverse as automotive fuel systems to greenhouse films. ETFE has a long history of use as electrical […] Read more

When applied to aircraft wire systems technology, what is “delamination”?

January 1, 2007 Lectromec Team

Some failure mechanisms in aircraft wire systems technology are easy to find. Among the failure mechanisms faced by a wire, one is often overlooked: the failure of the layer to layer bond of wrapped wire insulation. When the bonding material fails to hold together the successive wraps of insulation, this is known as delamination. The basic construction […] Read more

Chemical formulas and structures for wire systems

December 18, 2006 Lectromec Team

Elemental abbreviations that may be used for wire systems C = carbon H = hydrogen Cl = chlorine N = nitrogen F = fluorine O = oxygen Structure I Structure II Structure III Structure IV Structure V […] Read more

Aircraft wiring material considerations beyond insulators and conductors

December 12, 2006 Lectromec Team

The basic tool kit to understand aircraft wiring goes beyond some of the basics. Here are some topics of interest: Materials that are insulators There are a large number of materials that are insulators and they can be either inorganic or organic. Practically all organic materials that are used for insulation purposes are polymers. Inorganic materials […] Read more

By: Lectromec Team