Airworthiness Compliance Approach Of Fatigue Assessment For The Modification Design Of Helicopter

By virtue of its superior maneuverability, Helicopter has been employed more and more widelyin transportation, aerial, search and rescue and power operation and other fields.However, tasks indifferent areas put forward different specific requirements on the helicopter. For example, externalphotographic equipment installed outside the helicopter is required in aerial, where necessarily thehelicopter should be specially adapted to improve the working performance in special occasions.Whereas the helicopter, as civil aircraft, in order to ensure that the safety of its operation and flightperformance is not affected, the helicopter modification must be submitted to the CAACairworthiness Department to execute airworthiness certification and compliance, to meet thecorresponding airworthiness rules to guarantee its operation and flight performance. Theairworthiness certification of The modification design of helicopter is required to complete thefollowing work: compliance check list, compliance notes, engineering instruction, ContinuousAirworthiness document, Flight Manual Supplement page, stress analysis report, weight and balanceanalysis, environmental testing (select), electromagnetic compatibility testing, fatigueassessment,etc.This paper will address the demands mentioned above, make a research and analyze deeplyairworthiness regulations and relevant provisions related to modification design of the helicopter. Onthe basis of this, combined with the relevant airworthiness regulations for fatigue assessment and thetheoretical basis of fatigue analysis, make a approach and put forward the fatigue structureidentification method flight spectrum and load spectrum formulation method, specific operationmethod of the fatigue analysis and test involved in the fatigue assessment executed in themodification design of the helicopter. The compliance approach will be applied in the airworthinesscompliance verification project of the actual helicopter modification design.