Surge and rotating stall in compression system are two types of aerodynamic unstable phenomenons often encountered during the operation of aero-engines. The stall/surge characteristics clauses of China Civil Aviation Regulations (CCAR) 3365 in the regulations were analyzed. And Rotor 67 was taken as the research object

a rapid estimation method of engine surge/stall margin under the influence of crosswinds was established from the perspective of airworthiness approval. The results of this method showed that when the crosswind velocity was 35m/s

the surge margin at take-off decreased by 51%

and the surge margin on landing decreased by 198%.