Overspeed Protection System and Method

A method for providing overspeed protection for a gas turbine engine, the gas turbine engine comprising an engine shaft, a combustion section, and a variable geometry component, the variable geometry component comprising an actuator, the method comprising:

• determining an overspeed condition of the engine shaft;
• restricting a fuel flow from the combustion section of the gas turbine engine in response to the overspeed condition;
• directing the fuel flow to the actuator of the variable geometry component in response to the determined overspeed condition;
• and
• positioning the variable geometry component in an airflow inhibiting position with the actuator to reduce a rotational speed of the engine shaft.

An overspeed protection system for a gas turbine engine defining a flowpath and a central axis, the gas turbine engine comprising a combustion section and an engine shaft, the overspeed protection system comprising:

• a variable geometry component for positioning in the flowpath radially outward from the central axis of the gas turbine engine;
• an actuator in operable communication with the variable geometry component for moving the variable geometry;
• a control circuit in fluid communication with the actuator, the control circuit including an overspeed valve selectively positionable in a routine state and an overspeed state, the overspeed valve defining a fuel path to the combustion section of the gas turbine engine in the routine state, the overspeed valve defining a fuel path to the actuator in the overspeed state;
• and
• a controller in operable communication with the overspeed valve and the engine shaft, the controller configured for determining an overspeed condition based at least in part on information received from the engine shaft, the controller further configured for positioning the overspeed valve in the overspeed state in response to determining the overspeed condition.