What is OPAS on Boeing 737? (Overhead Panel Arinc 629 System)

The Boeing 737 aircraft is equipped with a range of advanced systems that ensure the safe and efficient operation of the aircraft. One such system is the Overhead Panel ARINC 629 System, commonly abbreviated as OPAS. This system plays a crucial role in the overall functioning and control of various aircraft components. In this article, we will take a closer look at the Overhead Panel ARINC 629 System and its significance on the Boeing 737 aircraft.

The Functioning of the Overhead Panel ARINC 629 System

The Overhead Panel ARINC 629 System on the Boeing 737 is a digital communication system that connects multiple aircraft components and allows for data exchange between them. This system is based on the ARINC 629 specification, which provides a standardized interface for digital communication in aircraft.

The OPAS consists of various components, including the overhead panel display, control switches, and the associated wiring harness. These components are installed in the cockpit and provide the pilots with a centralized interface to monitor and control different systems onboard the aircraft.

One of the primary functions of the Overhead Panel ARINC 629 System is to facilitate communication between the cockpit and the aircraft’s avionics systems. This includes systems such as the flight management system, autopilot, navigation systems, and engine control units. The OPAS allows for the transfer of data, commands, and status information between these systems, enabling seamless coordination and operation.

In addition to facilitating communication between systems, the Overhead Panel ARINC 629 System also enables centralized monitoring and control of various aircraft functions. Through the overhead panel display and control switches, pilots can access and manipulate important parameters such as fuel levels, electrical systems, hydraulic systems, and environmental controls. This ensures that the aircraft operates within safe and optimal limits throughout the flight.

Advantages of the Overhead Panel ARINC 629 System

The implementation of the Overhead Panel ARINC 629 System on the Boeing 737 aircraft offers several advantages in terms of safety, efficiency, and convenience.

1. Enhanced Safety: The OPAS allows for real-time monitoring and control of critical aircraft functions. Pilots can quickly identify and respond to any anomalies or abnormal conditions, ensuring the safety of the flight and its passengers. The centralized nature of the system also minimizes the chances of human error or oversight.

2. Improved Efficiency: With the Overhead Panel ARINC 629 System, pilots have access to a comprehensive set of controls and indicators, all located in one central panel. This streamlines their workflow and reduces the time required for system monitoring and control. The digital communication capabilities of the system also expedite data exchange between systems, leading to faster decision-making and response times.

3. Simplified Maintenance: The OPAS simplifies troubleshooting and maintenance processes by providing a centralized interface for system diagnostics. In the event of a malfunction or fault, engineers can easily access the system and retrieve relevant data for analysis and repair. This reduces aircraft downtime and improves overall operational efficiency.


The Overhead Panel ARINC 629 System is a critical component of the Boeing 737 aircraft, enabling efficient communication, monitoring, and control of various systems. Its implementation enhances safety, improves operational efficiency, and simplifies maintenance processes. As the aviation industry continues to evolve, advancements in digital communication systems such as the OPAS will play a pivotal role in shaping the future of aircraft operations.

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