EWIS: What is it and why is it important?

Welcome to the world of aircraft safety and maintenance, where Electrical Wiring Interconnection Systems, or EWIS, play a pivotal role in keeping flights safe and efficient.


Imagine EWIS as the nerve centre of an aircraft, transmitting vital electrical power and signals to various crucial components. From defining its components to understanding its significance in modern aviation, we’ll delve into the challenges, safety concerns, regulatory standards, and maintenance practices surrounding EWIS.

So buckle up as we embark on a journey to explore the heartbeat of aircraft safety and learn why keeping EWIS in top condition is paramount for safe skies.

If you’re keen to learn more about EWIS maintenance, Bostonair offers comprehensive Online Training courses.


EWIS, or Electrical Wiring Interconnection Systems, is a vital part of aviation safety and upkeep. Here’s what you need to know:



EWIS encompasses all the wires, cables, connectors and related parts that carry electrical power and signals throughout an aircraft, such as wiring harnesses and junction boxes.

Importance of EWIS

Modern aircraft rely heavily on electrical systems for functions like avionics, lighting and flight controls. Keeping EWIS reliable is crucial for safe and effective flight operations, so engineers have to keep up with the latest training and updates.


EWIS faces various environmental factors like temperature changes and moisture, which can cause wear and tear over time, especially in older aircraft which are susceptible to EWIS-related issues.

Safety concerns

Faulty wiring or electrical malfunctions can pose serious safety hazards, including electrical fires, equipment failures or loss of critical systems. In extreme cases, EWIS-related incidents can lead to accidents or in-flight emergencies.

Regulatory Standards

Aviation authorities, such as the Federal Aviation Administration (FAA) in the United States or the European Union Aviation Safety Agency (EASA) in Europe, establish regulations and standards governing the design, installation, maintenance, and inspection of EWIS to ensure airworthiness and safety.

EWIS Maintenance:

Regular inspection, testing, and maintenance of EWIS are essential to identify and address potential issues before they compromise safety or performance. Maintenance tasks may include visual inspections, continuity checks, insulation resistance testing, and connector cleaning.

Aging Aircraft Concerns:

As aircraft age, the risk of EWIS-related failures increases due to factors such as wire degradation, connector corrosion, and insulation breakdown. Ageing aircraft programs aim to mitigate these risks through enhanced inspection and maintenance procedures and retrofitting or replacing ageing wiring components.

Training and Awareness:

Aircraft maintenance personnel, engineers, and technicians receive training on EWIS maintenance practices, safety protocols, and regulatory requirements to ensure compliance and competency in handling electrical systems.


Interested in learning more about EWIS? Bostonair offers EWIS online training courses, including EWIS Group 1 & 2, EWIS Group 3 & 4, EWIS Group 5 & 6, EWIS Group 7 and EWIS Group 8.
Head to our Online Training page to find out more…