What is Trailing-Arm Landing Gear and Its Uses?

Landing gear is one of the most critical subsystems in aircraft. Regardless of the airplane type, almost all aircraft rely on landing gear for takeoffs and landings. It is usually designed with minimum weight and volume, high-performance characteristics, and more. More than that, it is made to absorb and dissipate the kinetic energy of landing impact in order to reduce the overall impact loads transmitted to the airframe.

Using the wheel braking feature, landing gear provides directional control of the aircraft, allowing pilots to brake with ease. Furthermore, landing gear is often made retractable to minimize aerodynamic drag on aircraft during flight. Upon landing, pilots will lower the aircraft’s landing gear out of the undercarriage. Generally, landing gear consists of a set of hydraulically-powered wheels.

While a majority of landing gear systems feature hydraulically-powered wheels, some variations take advantage of a different suspension system. For instance, trailing-arm landing gear is one type that is characterized by its suspension system. Trailing-arm landing gear features an L-shaped strut and a shock-absorbing strut. With these specialty struts, trailing-arm landing gear allows pilots to execute smoother landings. It also absorbs the shock of the aircraft as it touches down on the runway. Additionally, the use of trailing-arm landing gear enables aircraft to roll more smoothly when taxiing.

Other types of landing gear systems will usually only feature a single strut. Meanwhile, in trailing-arm landing gear systems, the shock-absorbing strut is connected to the bottom part of the L-shaped strut. The L-shaped strut is designed to pivot in front of the wheel with which it is used. Most trailing-arm landing gear utilize oleo struts to absorb shock. Oleo struts are pneumatic-hydraulically powered and contain both air and oil. When landing, oleo struts compress, which forces the air and oil within them to compress as well. In terms of components, most oleo struts consist of an inner piston, outer tube, gas and air, and seals.

Similar to most aircraft systems, trailing-arm landing gear does not have an ever-lasting service life and necessitates regular inspections. It should be checked on a routine basis to ensure that it is working optimally, as malfunctioning gear can have detrimental consequences. Some of the most common causes of landing gear failure include improper repair or maintenance, worn out parts, incorrectly secured components, ruptured hydraulic lines, and electrical issues, among others.

The aforementioned issues can be prevented through the implementation of in-depth servicing intervals that assess the aircraft’s various subsystems, ensuring that they are operating as intended. For instance, the 2016 aircraft accident involving a FedEx cargo flight highlighted the importance of landing gear maintenance. Federal investigators explained that the failure of the landing gear was attributed to corrosion that led to internal metal cracking. They noted that it could have been prevented had the airline conducted a detailed inspection of the aircraft prior to takeoff. According to the National Transportation Safety Board (NTSB), the left landing gear cracked and collapsed due to internal wear and was not coated with the required cadmium to reduce damage.

If, during maintenance, you realize you need replacement parts for your landing gear or other related components, rely on ASAP Aerospace Hub. ASAP Aerospace Hub is a leading distributor of top-quality aviation products, all of which are sourced from top global manufacturers that we trust. Kickoff the procurement process with a competitive quote on any featured item(s), and in as little as 15 minutes, a dedicated representative will reach out with a customized solution. For questions about our other offered services, call or email us at any time; we are available around-the-clock!