1. A method for tracking an operation of an identified airplane engine, the method comprising: acquiring first data from a plurality of airplane engines; storing the first data in a generic database; training at least one statistical regression function in connection with the generic database for establishing a generic behavior model of the plurality of airplane engines; acquiring second data from the identified airplane engine; storing the second data in a specific database specific to the identified airplane engine; resetting the generic behavior model in connection with the second data stored in the specific database for establishing a specific behavior model that takes into account features specific to the identified airplane engine; and tracking the operation of the identified airplane engine based on the specific behavior model, wherein the generic and specific databases include degradation indicators (t) and context variables (v i ), wherein training the at least one statistical regression function further comprises: determining a regression function (f t ) for each context variable (v i ) having an influence on at least one degradation indicator (t) obtained from the generic database, and modeling each degradation indicator (t) by optimizing the regression functions (f i ), wherein resetting the generic behavior model further comprises optimizing each degradation indicator (t) by an additional statistical regression in connection with the specific database for leaving only an affine resetting function as degrees of freedom, and wherein tracking the operation of the identified airplane engine further comprises measuring a value of the degradation indicator (t) and corresponding context variables (v i ) while the identified airplane is in flight, using the additional statistical regression for estimating a value expected for the degradation indicator (t) as a function of the measured corresponding context variables (v i ), and calculating a difference between the expected value for the degradation indicator (t) and the measured value of the degradation indicator (t).