A method of aeroengine flight load spectrum prediction is developed,which uses principles of aircraft flight mechanics to turn aircraft design mission profiles into engine thrust profiles.Flight altitude and flight velocity are acquired by solving the aircraft motion equations with the aircraft motion constraints.In the result of the engine performance calculations,the other engine operating parameters can be obtained.In the flight process from take-off to landing,taking the final value of the previous operation as the initial value of the following one,the engine flight load spectrum can be calculated for a specific flight mission.As an example,the flight load spectrum of an engine used on a trainer has been calculated.