Landing Gear System

The Landing Gear System

The landing gear system supports the aircraft's weight on the surface. Also, it is responsible for resisting high loads on landings without damage while providing comfort to everyone on board. (Makhlouf & Aliofkhazraei, 2015 ). This system usually consists of wheels; however, skies or floats are an alternative, depending on the type of aircraft (FAA, 2016). Additionally, other components, such as the brakes assembly and hydraulic lines, are part of the system.

The Main Gear of a B737NG

Like any other system, the landing gear is subject to malfunction, even on aircraft with rigorous maintenance. Also, a failure on this system can endanger people on board, the airplane itself, and other people or airport facility near the aircraft. For this reason, pilots have to inspect the system before each flight thoroughly.   

Many things could go wrong with the landing gear system. Nevertheless, pilots are familiar with the troubleshooting procedures, and they have handbooks on the flight deck and electronic flight bags that describes the procedures to follow after a failure. Typically, the malfunction of this system represents a time threat, which means pilots will have time to deal with the problem and does not constitute an immediate danger to the aircraft.

One of the least issues this system could have is a flat tire. Similar to a car, this could happen for many reasons; the most common is due to a tire worn out. If this happens, the aircraft should stop immediately. Otherwise, the friction could damage the wheel disk. However, in extreme cases, a flat tire could lead to a fatal accident such as on the Air France Flight 4590.

G450 abnormal gear position

For instance, if the gear is stuck down, the airplane won't be able to accelerate due to the amount of drag generated by the structure. Therefore, the engines would have to produce more thrust to climb at an average climb speed and to maintain a normal cruise airspeed. Consequently, more fuel is needed, a fuel that was not planned, and most likely, a return to the field would be required.

E190's nose gear did not deploy.

Conversely, one of the gears might not come to the down and locked position. This problem usually happens in the approach phase; at this time, pilots should discontinue the approach and deal with the issue. The gear is kept in the up position by hydraulic pressure; therefore, pilots must remove that pressure following the appropriate procedure. However, if pilots are unable to bring the gear down, gear up landing must be planned.

A320 nose gear failure.

The worst issue the landing gear system could experience is a structural failure. Many factors could lead to this problem, from the environment to overloading the landing gear. If the structure is damaged, the gear could collapse. This failure could happen without any noticeable indication, and that is why this is the worst. Often maintenance technicians can recognize this issue on aircraft inspections.

References:

• 737NG nose landing gear. (n.d.). Retrieved from http://www.b737.org.uk/landinggear.htm#General

• Landing Gear 101. (n.d.). G450 Abnormal Gear Condition. Retrieved from http://code7700.com/g450_landing_gear_abnormals.htm

• Pilot’s handbook of aeronautical knowledge : 2016 (First Skyhorse Publishing edition.). (2016). New York, NY: Skyhorse Publishing. 

• Makhlouf, A. S. H., & Aliofkhazraei, M. (2015). Handbook of materials failure analysis with case studies from the aerospace and automotive industries: With case studies from the aerospace, chemical, and oil and gas industries. Burlington: Elsevier Science. 

• The Associated Press. (2019). Rescue team gather near a plane of Myanmar National Airline (Mna) after an accident at Mandalay International airport Sunday, May 12, 2019, in Mandalay, Myanmar. All passengers and crew are reported safe and uninjured after a Myanmar National Airlines plane made a scheduled but emergency landing at Mandalay International Airport on only its rear landing wheels after the front landing gear failed to deploy. (Aung Thura via Ap). Retrieved from https://abcnews.go.com/International/wireStory/myanmar-passenger-jet-lands-safely-landing-gear-fails-62986476

• The rear-most tire is dragging and about to catch fire. (2005). Retrieved from http://www.airlinesafety.com/editorials/JetBlueLAX.htm