Structural Reliability Analysis Of A Landing Gear And Functional Reliability Experiment Of An Up Latch

In order to realize the landing gear's high reliability design, more attention should be paid to the reliability problems. The work begins with establishing a feasible fatigue reliability analysis model for reliability analysis of a landing gear. Considering the design requirement of a nose langding , the failure modes and effects and fault tree analysis of an up latch is carried out and the latch mechanism reliability experiment system is triturated meeting to the test requirement. At last, the functional reliability of the latch is effectively examined."Cumulative damage-critical damage"dynamic interference model based on Miner linear fatigue damage theory is established for convenional reliability analysis. On that basis,the transitional process from security state to failure state is considered as a fuzzy event. Fuzzy math theory is applied to describe the uncertainty property of the model which can't be handled by conventional fatigue reliability method. At last, the variable reliability along with the of fatigue life of the landing gear is obtained.The up latch of a landing gear is analized by failure modes and effects analysis and fault tree analysis, through which the experimental plan is designed. An up latch functional reliability experiment system is developed. It proposes a new directly imposing method of landing gear aerodynamic loads and the problem of how to impose separately in retraction and extension process of landing gear is solved. Also the maximum error of load simulation is less than 8%. The importance of power for the latch function is effectively examined .