AI Express Sharjah-Bound Flight Suffers Hydraulic Failure: What Happens When A Plane Loses Control?

In a dramatic incident, an Air India Express flight, AXB613 IX613, bound for Sharjah from Trichy, found itself circling over the city for nearly two hours due to a technical glitch. The Boeing 737, carrying 141 passengers, encountered a hydraulic system issue shortly after taking off from Trichy Airport.

According to reports, the aircraft took off at approximately 5:45 PM but soon faced complications that prompted the pilots to keep the plane aloft to burn off fuel before attempting a safe landing. The flight, carrying 141 hopeful travelers on their way to the United Arab Emirates, was met with an unexpected delay after reports emerged of a hydraulic system issue. As the plane made its rounds above the city, the crew worked diligently to ensure a safe landing at Trichy Airport.

What Are Hydraulic Systems and Why Are They Important for Aircraft?

Aircraft are equipped with various movable surfaces essential for flight control. These include:

• Ailerons: Located on the wing's trailing edge near the wingtips, ailerons move up and down, allowing pilots to roll or bank the aircraft.
• Elevators: Mounted on the aircraft's tail, elevators also move up or down and control the pitch, enabling the plane to climb or descend.
• Rudder: The vertical fin on the aircraft's tail moves left or right, allowing pilots to control the yaw, or lateral movement, of the aircraft. The rudder also aids in maintaining directional control during takeoff and landing.

These flight control surfaces are critical; without them, pilots cannot steer the aircraft, bank, climb, or descend. This is where hydraulic systems play a vital role, particularly in larger jets, where ailerons, elevators, and rudders are operated by hydraulic mechanisms.

The Role of Hydraulics in Aircraft

Hydraulics are utilized for various essential movements, including:

Landing Gear: The extension and retraction of the aircraft's landing gear.
Flaps and Slats: These are mounted on the wings' leading and trailing edges and are extended during takeoff and landing to increase lift.
Spoilers: Located on top of the wings, spoilers are deployed to slow the aircraft.
Wheel Brakes and Thrust Reversers: These systems help in stopping the aircraft after landing.
Horizontal Stabilizer: This is the small wing-like structure on the aircraft's tail where the elevators are mounted.

How Do Aircraft Hydraulics Work?

Pilots control the movement of the ailerons, elevators, and rudder using the sidestick or yoke (in Airbus and Boeing aircraft, respectively) and rudder pedals in the cockpit. They also use levers or switches for other control surfaces and landing gear. However, the physical force exerted by pilots is insufficient to move the large, heavy control surfaces due to air pressure acting on them during flight.

To amplify the pilot's input, an aircraft's hydraulic system uses pressurized fluid, which transfers the "magnified force" to actuators that move the control surfaces. Whether in manual flight or on autopilot, the hydraulic fluid powers these actuators.

While smaller aircraft may not have fully hydraulic control surfaces or may only use hydraulics for specific components, all large passenger jets rely on hydraulic systems for their control surfaces.

What Happens When an Aircraft's Hydraulics Fail?

Hydraulic failure can occur due to various reasons, such as fluid leaks, overheating, faulty components, or physical damage to hydraulic lines. Such failures can compromise the system during flight.

Fortunately, aircraft are designed with multiple redundant systems for safety. Modern planes typically have multiple hydraulic systems, so if one fails, a backup system is available. It is unlikely for all hydraulic systems to fail simultaneously.

In cases of hydraulic failure, certain systems can be operated manually. For instance, the landing gear can often be extended manually using an alternative mechanism that allows it to drop under the force of gravity.

Thanks to advancements in aircraft hydraulic engineering, catastrophic failures are now rare. However, in the event of a hydraulic failure warning, pilots assess the situation and may divert to the nearest airport to land quickly, prioritizing safety and passenger comfort. There have been instances where leaking hydraulic fluids entered the aircraft cabin, necessitating an evacuation.