Study On The Method To Improve The Rate Of Primary Repair Of Lift Components Of A Helicopter

With the rapid development of China's economy and society and the solid progress of China's military modernization,helicopters are increasingly used in military and non-military operations,this puts forward a higher requirement for the maintenance support ability of the helicopter,which is also a huge test for our aviation repair factory.It can be said that the quality of helicopter maintenance support capability directly affects the level of helicopter performance,safe and reliable maintenance support capability is one of the most important factors for a helicopter to perform its mission to the maximum efficiency,therefore,aviation repair factories need to continuously improve their maintenance support capacity.In this paper,the problem of repeated troubleshooting of a certain type of helicopter lift parts repaired by the factory after installation is discussed.Compared with similar models,the rate of one-time repair is low,and the rate of one-time repair cannot meet the user's satisfaction,which has become a problem in urgent need of improvement in repair.The following work was mainly carried out:(1)summarize the common faults of helicopter lift components and their troubleshooting methods.According to the maintenance support situation of lift parts in the factory,the troubleshooting situation in the field and the maintenance experience,the common faults of lift parts and the troubleshooting methods are summarized.(2)analyze the main factors that lead to the unqualified rate of lift components in the first repair.Based on the investigation and analysis of the repair situation of lift parts in 2016,the main reason for the unqualified rate of the first repair of lift parts was found to be the tail rotor unbalance and out-of-tolerance fault.Through inspection,analysis,field test and other methods,the final determination of the three main factors affecting the tail rotor unbalance and out-of-tolerance fault,that is,excessive use of the balance shaft,balance shaft and the product with a large gap,tail blade repair process without water removal requirements.(3)study the method to improve the qualification rate of lift components in the first repair.Through the selection and determination of countermeasures and the implementation and verification of methods,the specific methods for improving the qualification rate of lift components in the first repair are clearly put forward: repairing the worn balance shaft,changing the size,structure and assembly mode of the balance shaft,and increasing the drying requirements of tail blade after repair.(4)analyze and verify the improvement results.After the implementation of the improvement,the qualified rate of the first repair of tail propeller and the qualified rate of the first repair of lift parts both exceeded the expected target of 98.69%,and the improvement target was achieved.(5)take consolidation measures.According to the improved method,the requirements of checking the deformation of the balance shaft and drying the tail blade are included in the repair process.This paper studies and puts forward the specific countermeasures and methods to improve the qualification rate of lift parts in the first repair by improving tooling equipment and technological process.The analysis of the effect of the improvement measures shows that the qualified rate of the first repair of helicopter lift components increases from 96.73% to99.04%,which achieves the expected effect and has certain innovation and practicability.