Aircraft Systems - 07 - Hydraulic System

Summary

This video script explores the role of hydraulic systems in both small general aviation airplanes and large jets. It explains how smaller aircraft use hydraulic systems to operate brakes, landing gear, and propeller blade angles, while larger jets rely on hydraulics for flight controls and flaps. The script details the components of a hydraulic system, including the reservoir, pump, filter, and actuators, and describes how the system works to move fluid through lines, creating significant pressure to control various functions. The example of a brake system on a general aviation plane illustrates how hydraulic pressure powers the braking process.

Takeaways

• 😀 Nearly all airplanes are equipped with hydraulic systems, with smaller general aviation planes having simpler systems and larger jets using complex ones.
• 😀 In smaller airplanes, the hydraulic system powers essential functions like the brakes, landing gear, and some constant-speed propellers.
• 😀 In larger airplanes, hydraulic systems power critical components such as flight controls and flaps.
• 😀 A typical hydraulic system consists of a reservoir, pump, filter, relief valve, and actuators to control various aircraft components.
• 😀 Hydraulic systems work by pumping incompressible fluid through lines to actuators, causing piston movement to extend or contract.
• 😀 The hydraulic pressure exerted through actuators is significant, giving hydraulic systems great power and functionality.
• 😀 The brake system in general aviation airplanes uses hydraulic pressure to operate, starting from the brake pedals to the wheels.
• 😀 When a pilot presses on the brake pedal, fluid is moved through hydraulic lines to the actuator near the wheels, engaging the brakes.
• 😀 The fluid in the brake system pushes a piston that squeezes brake pads against the brake disc, slowing down the airplane.
• 😀 The hydraulic system's efficiency in transferring power makes it essential for controlling various airplane systems, especially in larger aircraft.

Q & A

What are hydraulic systems used for in airplanes?

Hydraulic systems in airplanes are used to power various components such as brakes, landing gear, and propeller blade angles in smaller airplanes, and more critical systems like flight controls and flaps in larger jets.

How do smaller and larger airplanes differ in their hydraulic systems?

Smaller general aviation airplanes typically have simple hydraulic systems that power basic functions like brakes and landing gear, while larger jets have more complex hydraulic systems that power critical flight controls, flaps, and other important systems.

What are the main components of a hydraulic system in airplanes?

A hydraulic system in airplanes typically includes a reservoir for storing hydraulic fluid, a pump to move the fluid, a filter to remove contaminants, a relief valve for malfunction protection, and actuators that operate various airplane components.

How does the hydraulic system work to control actuators?

The hydraulic system works by pumping incompressible fluid through hydraulic lines from one actuator to another, causing the actuator pistons to extend or contract, exerting significant pressure throughout the system.

What is the role of the hydraulic relief valve?

The hydraulic relief valve is designed to protect the system by releasing pressure in case of a malfunction or over-pressurization, preventing damage to the hydraulic system and other components.

What is the purpose of hydraulic brakes in a general aviation airplane?

Hydraulic brakes in a general aviation airplane are used to slow down the aircraft. When the pilot presses on the brake pedal, hydraulic fluid is moved through lines, activating a piston that squeezes the brake pads against the brake disc to create friction.

How does hydraulic fluid flow to the brake system in an airplane?

When the pilot applies pressure to the brake pedals, fluid is driven from the brake actuator through hydraulic lines and into the actuator near the wheels, where the fluid pushes a piston to engage the brakes.

What happens when the hydraulic system pressure is exerted on the actuators?

When hydraulic pressure is applied, the actuators' pistons either extend or contract, depending on the direction of the pressure, enabling movement of the components they control, such as landing gear or flight controls.

What are the benefits of using hydraulic systems in aircraft?

Hydraulic systems provide powerful, reliable control for various airplane functions, especially in larger aircraft where they manage critical systems such as flight controls and flaps. Their use of incompressible fluid also allows for more precise and efficient control.

Why is it important for hydraulic fluid to be kept free of contaminants?

Contaminants in hydraulic fluid can cause blockages, wear on system components, and failures in critical systems. A filter is used to keep the fluid clean and ensure smooth, safe operation of the hydraulic system.