A method of operation for a gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, reducing a rotational speed of a fan relative to a shaft through a gear train, driving the shaft with a first turbine, driving a compressor with a second turbine, communicating airflow from the fan through a bypass passage defined by a nacelle, the nacelle extending along an engine axis and surrounding the fan, and having a bypass ratio of greater than 10, discharging the airflow through a variable area fan nozzle defining a discharge airflow area, detecting an airfoil flutter condition associated with adjacent airfoils of the fan, and moving the variable area fan nozzle to vary the discharge airflow area and mitigate the airfoil flutter condition.