Why Do Planes Start Their Engines Before Taxiing?

When you’ve ever laid eyes on an aircraft on the ground, chances are, you’ve witnessed the engines being started before the plane starts moving. You might be surprised to learn that this action is crucial for the plane to taxi safely and efficiently on the ground. In this article, we’ll explore why planes must start their engines before taxiing and why it is necessary for their operation.

The Role of Engines and Wheels in Aircraft Operation

Aircraft wheels are not directly connected to the engines; they are free-rolling and designed for navigation on the ground. In order to move the aircraft, you have two main options: either use a tug or utilize the thrust generated by the engines themselves. This is why it is imperative that the engines are running before the plane commences its taxiing maneuvers.

Why Not Use a Tug?

A tug is a vehicle used to move the aircraft on the ground, but it has its limitations. The tug is useful for short movements or in situations where the aircraft’s engines need maintenance or are not operational. However, a tug cannot move the plane for long distances or at high speeds necessary for taking off. Additionally, a tug cannot maneuver the plane in complex directions or over long distances, which is why the engines are crucial for these operations.

Why Engines Are Essential for Taxiing

There are several reasons why aircraft engines are necessary for taxiing:

Directional Control: Thrust from the engines allows the pilot to control the direction of the plane more precisely, especially during turns and on curved taxiways. Speed Control: Engines enable the plane to taxi at different speeds, which is necessary for safety and efficiency. A combination of forward and reverse thrust can be used to control speed. Safe Movement: Engines provide the necessary power to move the plane safely on the ground, ensuring that the plane can navigate over obstacles, uneven terrain, and other ground vehicles without difficulty.

Can Planes Not Start Their Engines Before Taxiing?

No, planes cannot taxi without starting their engines. This is an absolute necessity for several reasons:

Pilots rely on engine thrust to steer the plane on the ground, giving them greater control over the aircraft. The engines provide essential power to overcome the friction and resistance between the wheels and the ground, allowing the plane to move smoothly and efficiently. Engines are needed to de-ice or de-fog the plane, which is crucial for safe takeoff and landing. Engines can perform checks and diagnostics during taxiing, ensuring that the aircraft is in a safe operating condition before takeoff.

Challenges of Taxying Without Engines

Trying to taxi without the engines would present significant challenges and potential hazards, such as:

Limited Control: Without engine thrust, pilots would lose control over the plane's direction and speed, increasing the risk of accidents or collisions. High Friction: The wheels would encounter high friction, making it difficult and unsafe to move the plane. Equipment Damage: The lack of adequate power could result in damage to the aircraft and the surrounding infrastructure. Fuel Consumption: Without the engines running, fuel lines and systems might not circulate properly, leading to issues that could impact safety.

Conclusion

In conclusion, starting the engines before taxiing is an essential step in ensuring the safe and efficient movement of an aircraft on the ground. Whether moving to the runway, parking, or navigating through the complex environment of an airport, the engines provide the necessary power and control. While a tug can be used in certain scenarios, engines are indispensable for maintaining the stability, safety, and efficiency of the aircraft during taxiing.