Investigation on the Characteristics of the Landing Gear Strut Lock Mechanism Based on Multi-body Dynamic Simulation Analysis

ZHANG Xinxin; ZHAO Bing

doi:10.7643/issn.1672-9242.2026.08.015

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Equipment Environmental Engineering ›› 2026, Vol. 23 ›› Issue (8) : 126-133. DOI: 10.7643/issn.1672-9242.2026.08.015

Investigation on the Characteristics of the Landing Gear Strut Lock Mechanism Based on Multi-body Dynamic Simulation Analysis

ZHANG Xinxin, ZHAO Bing

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Abstract

Focusing on the landing gear strut lock mechanism of a certain aircraft as the research object, the work aims to investigate the effects of factors such as lock strut deflection, main strut deflection, and friction on the mechanical characteristics and locking capability of the mechanism. Based on clarifying the working principle of the strut lock mechanism, the simulation analysis models of the strut lock mechanism with 9 lock strut deflection values, 11 main strut deflection values, and both static and dynamic characteristics were established. Compared to the initial lock strut deflection, the unlocking torque of the lock strut mechanism increased by 15.5% when the lock strut deflection reached its maximum. When the landing gear was in the retracted state and an upward overload of 2.5g was applied, the lock strut mechanism could maintain reliable locking within a deflection range of -14 to 0 mm. When the landing gear was in the retracted state and a downward overload of 2.5g was applied, as the lock strut deflection increased, the compressive load on the lock strut stop platform tended to decrease, and there was a tendency for unlocking when the lock strut deflection reached 18.5 mm. When the landing gear was in the extended state and upward and downward overloads of 2.5g were applied, the lock strut mechanism could maintain reliable locking within a deflection range of -14 to 0 mm. As the main strut deflection increased from negative to positive, the unlocking torque required by the strut lock mechanism gradually decreased. The tensile and compressive loads borne by the lock strut increased with the increase in main strut deflection. The friction forces of the main rotating shaft and the connecting joints of the upper and lower lock struts of the landing gear were sensitive to the unlocking torque and retracting torque of the lock strut mechanism, and good lubrication should be ensured. The research results provide a theoretical basis for the design of the landing gear strut lock mechanism and give the design boundaries for lock strut deflection.

Key words

landing gear / strut lock mechanism / deflection / load characteristics / dynamic simulation

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ZHANG Xinxin, ZHAO Bing. Investigation on the Characteristics of the Landing Gear Strut Lock Mechanism Based on Multi-body Dynamic Simulation Analysis[J]. Equipment Environmental Engineering. 2026, 23(8): 126-133 https://doi.org/10.7643/issn.1672-9242.2026.08.015

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