What is N on Airbus A320? (Normal, North)

When it comes to aviation, understanding the various systems and terminologies can be quite challenging. One such term that often raises questions is “Normal, North” on the Airbus A320 aircraft. In this article, we will delve into the meaning and significance of Normal, North and shed light on its role in aircraft operations. So, fasten your seatbelts as we take off into the world of Airbus A320!

The Importance of Normal, North

Normal, North (N) is an essential reference for the flight control systems of the Airbus A320. It serves as a baseline for various flight parameters and plays a crucial role in ensuring the aircraft’s stability and control. Let’s explore some key aspects influenced by Normal, North:

Fly-by-Wire System

The Airbus A320 boasts a highly advanced fly-by-wire system, where electronic signals transmit flight control inputs from the pilot to the aircraft’s control surfaces. This system relies on Normal, North as the reference point for pitch, roll, and yaw movements.

For instance, when the pilot moves the sidestick to pitch the aircraft up, the fly-by-wire system interprets the input relative to Normal, North. If the aircraft is currently flying level, this input will result in a pitch-up movement. However, if the aircraft is already in a nose-up attitude, the control system will compensate accordingly to maintain stability.

Furthermore, Normal, North is also crucial for the auto-trim function in the fly-by-wire system. Auto-trim automatically adjusts the aircraft’s trim (control surface position) to maintain stability when the pilot releases the sidestick. This feature relies on accurate reference data, with Normal, North serving as the baseline for trim calculations.

Navigation Systems

In addition to the flight control systems, Normal, North is integral to the navigation systems of the Airbus A320. The aircraft relies on the Magnetic Heading Reference System (MHRS) to determine its heading during flight. The MHRS uses a combination of magnetometers, gyros, and accelerometers to calculate the aircraft’s orientation in relation to magnetic North.

Normal, North provides the aircraft with a known reference point to establish its magnetic heading. This reference is essential for accurate navigation and is used by various systems such as the Flight Management System (FMS), Autopilot, and Electronic Flight Instrument System (EFIS).

It’s important to note that Normal, North is not constant and can vary slightly over time due to changes in the Earth’s magnetic field. Therefore, regular calibration and updates are necessary to ensure accurate navigation and avoid any potential discrepancies.

System Redundancy

The Airbus A320 incorporates a high level of redundancy in its systems to enhance safety and reliability. Normal, North plays a vital role in this redundancy, particularly in the Flight Control Laws and Navigation Laws.

In the Flight Control Laws, three channels exist: Normal, Alternate, and Direct. Normal Law is the standard operating mode, providing a wide range of automated flight protections and envelope limits. It relies on Normal, North as the reference.

In the event of a failure, such as a fault in the Normal Law, the fly-by-wire system automatically transitions to the Alternate Law. This mode maintains essential fly-by-wire functions but with reduced automation. Again, Normal, North serves as the reference for pitch, roll, and yaw movements.

In terms of Navigation Laws, the Airbus A320 employs both Magnetic and True navigation modes. Normal, North is essential for the Magnetic mode, providing the necessary heading reference. However, in the True mode, the reference shifts to True North for navigation calculations.

Having these redundant systems ensures that the aircraft remains controllable and navigable in various scenarios, even in the presence of failures or abnormal situations.


Normal, North plays a fundamental role in the Airbus A320 aircraft, providing the reference point for flight control systems and navigation. This term serves as the baseline for various critical functions, including pitch, roll, yaw movements, navigation calculations, and system redundancies. Understanding the significance of Normal, North enables pilots, engineers, and aviation enthusiasts to grasp the intricacies of this advanced aircraft.

Next time you step on board an Airbus A320, remember the importance of Normal, North and appreciate how this key reference contributes to the safety and reliability of your journey!

For More: What is ABN on Airbus A320? (Abnormal)