An air turbine starter for a gas turbine engine comprising: a turbine wheel including a hub integrally attached to a turbine rotor shaft and a plurality of turbine blades extending radially outward from the hub; an inlet housing at least partially surrounding the turbine wheel; a nozzle located upstream from the turbine wheel and contained within the inlet housing defining an inlet flowpath between the nozzle and the inlet housing, the inlet flowpath directs air flow into the turbine blades; a plurality of turbine vanes rotatably connected to the nozzle, each turbine vane extending radially from the nozzle into the inlet flowpath towards the inlet housing, wherein the plurality of turbine vanes are operable to adjust air flow through the inlet flowpath by rotating each turbine vane, wherein each of the plurality of turbine vanes can be rotated to any selected angle (α) in between a fully closed angle and a fully open angle, the selected angle (α) is equal to 0° when at the fully open angle and the selected angle (α) is equal to 90° when at the fully closed angle; a sync-ring operably connected to each turbine vane, the sync-ring in operation rotates each turbine vane when the sync-ring moves; at least one actuator operably connected to the sync-ring, the least one actuator in operation moves the sync-ring; a controller in communication with the at least one actuator, wherein the controller is configured to operate the at least one actuator in response to turbine blade airflow requirements of the air turbine starter to mitigate a bowed rotor condition of the gas turbine engine; and a speed sensor in communication with the controller, the speed sensor in operation detects an angular velocity of the turbine rotor shaft, wherein the controller in operation determines the turbine blade airflow requirements of the air turbine starter to mitigate the bowed rotor condition in response to an angular velocity of the gas turbine engine operable connected to the air turbine starter, an angular velocity of the turbine rotor shaft, and a pressure upstream of the air turbine starter. a turbine wheel including a hub integrally attached to a turbine rotor shaft and a plurality of turbine blades extending radially outward from the hub; an inlet housing at least partially surrounding the turbine wheel; a nozzle located upstream from the turbine wheel and contained within the inlet housing defining an inlet flowpath between the nozzle and the inlet housing, the inlet flowpath directs air flow into the turbine blades; a plurality of turbine vanes rotatably connected to the nozzle, each turbine vane extending radially from the nozzle into the inlet flowpath towards the inlet housing, wherein the plurality of turbine vanes are operable to adjust air flow through the inlet flowpath by rotating each turbine vane, wherein each of the plurality of turbine vanes can be rotated to any selected angle (α) in between a fully closed angle and a fully open angle, the selected angle (α) is equal to 0° when at the fully open angle and the selected angle (α) is equal to 90° when at the fully closed angle; a sync-ring operably connected to each turbine vane, the sync-ring in operation rotates each turbine vane when the sync-ring moves; at least one actuator operably connected to the sync-ring, the least one actuator in operation moves the sync-ring; a controller in communication with the at least one actuator, wherein the controller is configured to operate the at least one actuator in response to turbine blade airflow requirements of the air turbine starter to mitigate a bowed rotor condition of the gas turbine engine; and a speed sensor in communication with the controller, the speed sensor in operation detects an angular velocity of the turbine rotor shaft, wherein the controller in operation determines the turbine blade airflow requirements of the air turbine starter to mitigate the bowed rotor condition in response to an angular velocity of the gas turbine engine operable connected to the air turbine starter, an angular velocity of the turbine rotor shaft, and a pressure upstream of the air turbine starter.