What is LP on Boeing 737? (Low Pressure)

The Boeing 737 is a popular aircraft that has been a staple in the aviation industry for decades. As with any aircraft, it operates on the principles of aerodynamics, which involve the interaction of various pressures during flight. One such concept is low pressure, also known as LP, which plays a crucial role in the performance and safety of the Boeing 737. In this article, we will delve into what low pressure means for this aircraft and its impact on flight.

The Significance of Low Pressure on the Boeing 737

Low pressure refers to an area in the airflow where the air is less dense compared to its surroundings. In the context of the Boeing 737, low pressure primarily affects two key aspects: lift generation and engine performance.

Lift Generation and Low Pressure

Lift is the upward force that enables an aircraft to overcome gravity and stay airborne. It is created by the interaction of the aircraft’s wings with the surrounding air. Low pressure plays a critical role in lift generation on the Boeing 737.

When the Boeing 737 is in flight, the shape of its wings, known as airfoils, causes the air passing over the top surface to travel faster than the air passing underneath. This difference in airspeed leads to a decrease in pressure above the wing, creating a low-pressure area. The higher pressure below the wing pushes upward against the low-pressure area, generating lift.

According to Boeing’s design specifications, the wings of the 737 are optimized to generate the maximum amount of lift necessary for safe and efficient flight. The specific curvature and angle of the wings help create and control the low-pressure area, ensuring proper lift generation.

It is important to maintain the balance between low and high pressure during flight. An imbalance can lead to reduced lift, compromising the aircraft’s ability to stay airborne or maintain the desired altitude. Therefore, monitoring and controlling low pressure is crucial for the safe and reliable operation of the Boeing 737.

Engine Performance and Low Pressure

Low pressure also plays a significant role in the performance of the engines on the Boeing 737. The engine’s design and operation rely on the principle of pressure difference to generate thrust, which propels the aircraft forward.

Within the engine, air is compressed before combustion in the combustion chamber. This compression increases the pressure of the air, which is then mixed with fuel and ignited. The resulting expansion of gases creates a high-pressure exhaust, which is expelled out of the engine at high velocity, generating thrust.

However, to achieve efficient combustion and optimal engine performance, the air entering the engine needs to be at a specific pressure. This is where low pressure becomes crucial. The efficient operation of the engine requires a pressure difference between the surrounding air and the air entering the engine. This pressure difference ensures proper airflow and fuel combustion.

Various components within the engine, such as compressor blades and stators, are designed to take advantage of the pressure difference. These components work together to maintain the desired pressure and ensure the engine functions at its optimal level.

It is worth noting that extreme low-pressure conditions, such as those experienced during rapid ascents or descents, can have adverse effects on engine performance. Substantial pressure differences can lead to compressor stalls or surges, resulting in decreased efficiency and potential engine damage. As a result, pilots and aircraft systems are equipped with measures to mitigate these risks and ensure safe operations.


Low pressure is a critical factor in the flight dynamics and performance of the Boeing 737 aircraft. It plays a vital role in lift generation and engine performance, both of which are essential for safe and efficient flight operations. By understanding the significance of low pressure, aviation professionals can ensure proper maintenance, monitoring, and control of this important aspect, contributing to the overall safety and reliability of the Boeing 737.

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