LAUSR

Dear editor, Taxiing stability is an important issue in modern civil aircraft development and airworthiness certification. Incidents or abnormal problems consistently arise during aircraft taxiing, as a result of landing gear “walking”, shimmying, and taxiing directional instability. The vibrations or instability associated with a landing gear system may affect the aircraft’s normal directional control, shorten its service life, and even lead to runway excursion accidents. Therefore, taxiing stability verification has been an important concern for the development of a civil landing gear system. The taxiing stability of the landing gear is also one of the airworthiness requirements of the China Civil Aviation Regulations CCAR-25 (the Federal Aviation Administration of the United States has a regulation called 14CFR25). Section 25.233(c), “Directional stability and control”, states the following: “The aircraft must have adequate directional control during taxiing. This may be shown during taxiing prior to takeoffs made in conjunction with other tests” [1]. An amphibious aircraft is usually installed with more unique and complex landing gear, and thus, an assessment of the taxiing stability of the landing gear is deemed more necessary. Previous studies on the overall layout and taxiing stability of amphibious aircraft landing gear are relatively rare. In [2–4], a numerical simulation is the main approach to taxiing stability.