What is SHVR on Boeing 737? (Shaver)

The Boeing 737 is one of the most popular aircraft in the world, serving as a workhorse for airlines globally. It has a rich history, with numerous variants and improvements made over the years. One important system on the Boeing 737 that is essential for its safe operation is the Shaver system, also known as SHVR. In this article, we will explore what Shaver is, its significance, and how it contributes to the overall functionality of the Boeing 737.

Understanding the Shaver System

The Shaver system on the Boeing 737 is a key component of the aircraft’s fuel management system. It ensures that fuel is transferred efficiently between various fuel tanks during flight. The purpose of the Shaver system is twofold: to maintain proper fuel distribution throughout the aircraft and to prevent fuel imbalance that could affect the aircraft’s stability.

When an aircraft is in flight, fuel can shift due to changes in the aircraft’s attitude, such as banking during turns. The Shaver system helps counteract this by moving fuel between tanks to maintain balance. It consists of various pumps, valves, and sensors that work together to monitor and control fuel transfer.

Not only does the Shaver system ensure fuel balance, but it also helps manage fuel during different phases of flight. For example, during takeoff, the Shaver system focuses on fuel transfer from the center tank to the wing tanks to reduce the load on the center tank. During cruise, it maintains balance between the wing tanks, and during descent and landing, it transfers fuel back to the center tank for stability and balance.

The Shaver system operates automatically, controlled by the aircraft’s flight management computer. It continuously monitors the fuel levels and adjusts fuel transfer as required to maintain proper balance and prevent fuel starvation in any part of the aircraft.

Importance of the Shaver System

The Shaver system plays a crucial role in maintaining the safety and efficiency of the Boeing 737 aircraft. Proper fuel distribution is vital for the stability and control of the aircraft, especially during critical flight phases. Imbalanced fuel loads can lead to handling issues, increased drag, and potential fuel starvation, all of which can pose significant risks.

The Shaver system’s ability to automatically transfer fuel as needed helps ensure that the aircraft remains well-balanced, even under challenging flight conditions. This allows pilots to focus on flying the aircraft without having to manually manage fuel levels and distribution.

In addition to maintaining stability, the Shaver system also contributes to the overall efficiency of the Boeing 737. By optimizing fuel transfer, it helps reduce fuel consumption and improve the aircraft’s range. This translates to cost savings for airlines and reduced environmental impact.


The Shaver system, or SHVR, is a critical component of the Boeing 737 aircraft, ensuring proper fuel balance and distribution. Its automated operation and ability to maintain stability contribute to the safe and efficient operation of the aircraft. Without the Shaver system, managing fuel levels and distribution would be a challenging task for pilots, potentially compromising safety and increasing fuel usage.

As technology advances, the Shaver system continues to evolve, with newer Boeing 737 variants incorporating enhanced fuel management capabilities. The system’s importance in providing a safe and reliable flying experience cannot be overstated, making it an integral part of the iconic Boeing 737 aircraft.

For More: What is VHF on Boeing 737? (Very High Frequency)