What is NBR on Boeing 737? (Number)

When you see a Boeing 737 aircraft, you may notice a unique number displayed on its tail or fuselage. This number, known as the NBR or number, plays a crucial role in identifying and tracking the aircraft. In this article, we will delve into what the number on a Boeing 737 means, its significance, and how it is assigned to each individual aircraft.

Understanding the Number on a Boeing 737

The number on a Boeing 737 is a registration or tail number, which is like a license plate for an aircraft. This alphanumeric sequence uniquely identifies the specific aircraft and is displayed prominently on its exterior. The number helps to keep track of the aircraft’s ownership, maintenance history, and regulatory compliance.

The number consists of a combination of letters and digits. The prefix usually indicates the country of registration. For example, in the United States, the prefix is typically “N” followed by a hyphen and a series of digits. In other countries, different combinations of letters and numbers may be used.

Each country has its own regulatory authority responsible for assigning and managing these registration numbers. In the United States, the Federal Aviation Administration (FAA) is responsible for the registration and oversight of civil aircraft, including the Boeing 737.

Assigning the Number

So how are the numbers assigned to Boeing 737 aircraft? When a new aircraft is manufactured, it is given a temporary registration number by the manufacturer. This temporary number is used during the production, testing, and delivery phases.

Once the aircraft is ready for operation, the operator or owner applies for a permanent registration number with the regulatory authority of the country where the aircraft will be primarily based. The application process involves providing necessary documentation, including proof of ownership, maintenance records, and compliance with airworthiness regulations.

Upon successful completion of the registration process, the regulatory authority assigns a unique number to the aircraft. This number is then painted on the aircraft’s tail or fuselage, ensuring easy identification. The process may involve a fee, which varies depending on the country and its registration policies.

Significance of the Number

The number on a Boeing 737 holds several significant roles. Firstly, it helps air traffic controllers, ground staff, and airport authorities to identify and track the aircraft. By referring to the number, they can gather essential information about the aircraft’s ownership, registration status, maintenance history, and compliance with regulatory standards.

Secondly, the number plays a crucial role in accident investigation and safety monitoring. In the event of an incident or accident involving a Boeing 737, investigators can use the registration number to trace its operational history, previous maintenance records, and other relevant information that may help determine the cause of the incident.

Furthermore, the number aids in the identification of aircraft for regulatory purposes. Countries have specific regulations regarding the operation, maintenance, and airworthiness of aircraft. By using the number, authorities can ensure that a Boeing 737 complies with the necessary regulations and remains in safe operating condition.


The number on a Boeing 737 is more than just a combination of letters and digits. It serves as a vital identifier, helping to track the aircraft, determine ownership, and ensure regulatory compliance. This number plays a significant role in the aviation industry, from air traffic control to accident investigation and safety monitoring. So the next time you spot a Boeing 737, take a moment to observe its number and appreciate the valuable information it provides.

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