What is MAG on Boeing 737? (Magnetic)

The Boeing 737 aircraft, a prominent member of the commercial aviation industry, has captivated passengers and aviation enthusiasts for decades. With its sleek design, advanced technology, and impressive performance, it continues to be a popular choice for airlines worldwide. One intriguing aspect of the Boeing 737 is its use of magnetic components and systems. In this article, we will explore the role of magnetism in various aspects of the Boeing 737, highlighting its significance and impact on the aircraft’s operation and safety.

The MAG System: Enhancing Navigation Accuracy

One key area where magnetism plays a crucial role in the Boeing 737 is the Magnetic Anomaly Gradient (MAG) system. The MAG system is a component of the aircraft’s navigation system, specifically used for enhancing navigation accuracy.

The MAG system relies on the principle of magnetism to determine the aircraft’s heading and position. It utilizes magnetometers, which are devices capable of measuring the Earth’s magnetic field. By measuring the variations in the magnetic field, the MAG system can accurately calculate the aircraft’s magnetic heading.

This information is of paramount importance for the aircraft’s navigation, particularly during non-precision approaches and landings. Non-precision approaches refer to landing procedures that do not utilize a precision landing aid, such as the Instrument Landing System (ILS). Instead, pilots rely on other navigation aids, including the MAG system, to align the aircraft with the runway and make a safe approach.

The MAG system’s accurate determination of magnetic heading allows pilots to navigate more efficiently and precisely, especially in adverse weather conditions or areas where ground-based navigation aids are limited. This enhances the safety and reliability of the Boeing 737 during flight operations.

Magnetic Components in Avionics

Aside from navigation systems, magnetism also plays a role in various avionics components of the Boeing 737. Avionics, short for aviation electronics, encompasses the electronic systems used on aircraft to monitor, control, and communicate.

One such component is the magnetic compass, a critical instrument that provides pilots with information about the aircraft’s heading. Despite the advancements in modern navigation systems, the magnetic compass remains a primary backup for pilots, aiding them in situations where other instruments may fail.

Additionally, magnetism is utilized in the Boeing 737’s magnetically actuated control systems. These systems employ magnetic solenoids, which are electromechanical devices that convert electrical energy into linear motion. They play a vital role in controlling various aircraft functions, such as landing gear extension and retraction, flap operations, and spoiler deployment.

The use of magnetically actuated control systems enhances the aircraft’s reliability and simplifies the overall design. These systems are known for their durability, responsiveness, and ability to perform effectively even in harsh environments, ensuring the smooth operation of critical aircraft functions.

Electromagnetic Compatibility and Safety

Ensuring electromagnetic compatibility (EMC) is crucial in the design and operation of aircraft systems to prevent interference between different electronic components. The Boeing 737 incorporates various measures to achieve EMC, including magnetic shielding and proper grounding.

Magnetic shielding involves the use of materials that can redirect or absorb magnetic fields to prevent their interference with sensitive electronic components. These shielding mechanisms are strategically placed to protect areas where the magnetic field produced by electrical currents could adversely affect avionics systems.

Proper grounding is another essential aspect of achieving EMC. The Boeing 737 employs a comprehensive grounding system that ensures the safe dissipation of electrical currents and the prevention of unwanted electromagnetic interference. The proper grounding of electrical components helps maintain the integrity of signals and prevents disruptions in communication, navigation, and other critical systems on the aircraft.

By implementing electromagnetic compatibility measures, the Boeing 737 ensures the safe and reliable operation of its systems and minimizes any potential hazards or risks associated with electromagnetic interference.


The Boeing 737 aircraft, with its fusion of advanced technology and superior engineering, continues to be a trailblazer in the aviation industry. The use of magnetism in various aspects of the aircraft, from navigation systems to avionics components, significantly enhances its performance, reliability, and safety.

The Magnetic Anomaly Gradient (MAG) system, with its accurate determination of magnetic heading, allows for precise navigation even in adverse conditions. The presence of magnetic components in avionics, such as the magnetic compass and magnetically actuated control systems, adds to the aircraft’s resilience and operational efficiency.

Moreover, the emphasis on electromagnetic compatibility ensures the safe and reliable operation of the Boeing 737, mitigating any potential risks associated with electromagnetic interference. These magnetic elements and systems collectively contribute to the Boeing 737’s exceptional performance, making it an iconic aircraft in the global aviation landscape.

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