A method of calibrating a gas turbine engine having a propulsive fan, and an engine core, the method including: measuring a total thrust generated by the engine; measuring the thrust generated by the engine core; measuring first and second engine performance parameters; based on the total thrust and engine core thrust, determining a thrust generated by the propulsive fan; providing a first power setting parameter associating the fan thrust with the first engine performance parameter; and providing a second power setting parameter associating the engine core thrust with the second engine performance parameter.