What is E/E on Boeing 737? (Electrical And Electronic)

When it comes to aircraft systems, one area that plays a crucial role is the electrical and electronic (E/E) system. The Boeing 737, a popular narrow-body aircraft, relies heavily on this system for various functionalities. The E/E system encompasses a wide range of components and subsystems that work together to ensure the smooth operation of the aircraft’s electrical and electronic systems.

In this article, we will dive deep into the world of E/E on the Boeing 737 and explore its significance in powering the aircraft’s critical functions.

The Importance of Electrical and Electronic on Boeing 737

The electrical and electronic system on the Boeing 737 is responsible for powering and controlling various onboard systems. From communication and navigation to flight control and safety systems, E/E plays a vital role in keeping the aircraft operational and ensuring a safe and comfortable journey for passengers and crew.

The E/E system on the Boeing 737 consists of several components, including generators, batteries, distribution panels, wiring, and various electronic control units (ECUs) that oversee and manage different systems. These components work together seamlessly to provide reliable electrical power and ensure the proper functioning of critical aircraft systems.

The Components of the Electrical and Electronic System

The Electrical and Electronic system on the Boeing 737 comprises multiple components that contribute to its overall functionality. Let’s take a closer look at some of these essential components:


Generators play a crucial role in powering the aircraft’s electrical systems and charging the batteries. The Boeing 737 is equipped with engine-driven generators, typically located on the engines. These generators convert mechanical energy from the engines into electrical energy, which is then distributed to various systems.


Batteries provide electrical power when the engines are not running or in case of emergencies. On the Boeing 737, lead-acid batteries are commonly used. These batteries can supply power for critical systems, such as emergency lighting, when the main electrical sources are unavailable.

Distribution Panels

Distribution panels are key components in the E/E system as they distribute electrical power to different systems and subsystems. These panels receive power from the generators and batteries and ensure that each system receives the appropriate voltage and current.


Wiring forms the backbone of the E/E system, connecting various components and systems. High-quality wiring is essential to ensure reliable power distribution and communication between different parts of the aircraft. Boeing 737 uses advanced wiring technology to optimize performance and minimize maintenance requirements.

Electronic Control Units (ECUs)

Electronic Control Units (ECUs) play a critical role in monitoring and controlling different systems on the Boeing 737. These units receive inputs from sensors and other components, process the information, and initiate appropriate actions to maintain system functionality. ECUs are essential for flight control, engine management, and various safety systems.

The Integration of Electrical and Electronic Systems

The electrical and electronic systems on the Boeing 737 are meticulously integrated to ensure seamless functionality and system redundancy. Redundancy is crucial in aviation to enhance safety and prevent single points of failure. In the event of a component failure, backup systems are available to maintain critical functionalities.

One example of this integration and redundancy is the use of multiple generators and batteries. The presence of multiple generators ensures a continuous supply of electrical power, even if one generator malfunctions. Similarly, the batteries serve as backup power sources during emergencies or when the generators are unable to provide sufficient power.

The integration of E/E systems on the Boeing 737 also involves advanced communication protocols and data buses. These protocols and buses enable seamless communication and information exchange between different subsystems and components. They facilitate the flow of data from sensors to ECUs, allowing for real-time monitoring and control of various aircraft systems.

Furthermore, the Boeing 737 features advanced diagnostic and monitoring systems that continuously evaluate the health and performance of the E/E system. These systems can detect faults and anomalies, allowing maintenance crews to promptly address any issues and ensure the aircraft’s reliability and safety.

Overall, the electrical and electronic systems on the Boeing 737 are designed to provide efficient and reliable power distribution while maintaining the highest levels of safety and redundancy.


The electrical and electronic (E/E) system on the Boeing 737 is an essential component that contributes to the aircraft’s safe and efficient operation. From generators and batteries to distribution panels, wiring, and electronic control units, each part of the E/E system plays a crucial role in powering and controlling various onboard systems.

The integration of these components ensures seamless functionality and system redundancy, enhancing the safety and reliability of the aircraft. The advanced communication protocols, data buses, and diagnostic systems further optimize the performance and maintainability of the E/E system.

As technology advances, electrical and electronic systems on aircraft like the Boeing 737 continue to evolve, incorporating new features and improved efficiencies. It is through these advancements that the aviation industry can provide passengers with safe and enjoyable travel experiences.

For More: What is MCP on Boeing 737? (Mode Control Panel)