Abstract:Emergency break-away structure is used for critical connection area of aircraft,for example aircraft pylon,landing gear and flap structures. Its design and airworthiness are the key technologies of civil aircraft. Based on analysis of airworthiness requirements (CCAR-25) for emergency landing, a new method of the emergency break-away typical structure design and its airworthiness verification are proposed. Using this method,an emergency break-away typical structure test is designed. Test results show that this method complies with the airworthiness requirement of emergency landing, so it can be used for designing the emergency break-away typical structure and confirming its airworthiness compliance. Moreover,since the break-away time and failure criteria obtained in the test coincide with the ones of the theory analysis, this method has a practice value in civil aircraft emergency break-away typical structure design and its airworthiness verification.