A gas turbine engine, comprising: a compressor section; a turbine section operably connected to the compressor section; and a bleed air cooling system, including: a bleed port (58; 58a, 58b) disposed at an axial location of the gas turbine engine to divert a bleed airflow (66; 66a, 66b) from a gas turbine engine flowpath; a bleed outlet disposed at a cooling location of the gas turbine engine; a bleed duct (60; 60a, 60b) in fluid communication with the bleed port (58; 58a, 58b) and configured to convey the bleed airflow (66; 66a, 66b) from the bleed port (58; 58a, 58b) to the bleed outlet; a turbine manifold disposed between the bleed duct and the bleed outlet, the turbine manifold extending circumferentially around the turbine section to distribute bleed airflow to multiple circumferential locations of the turbine section; a modulating valve (74; 74a, 74b) disposed at the bleed duct (60; 60a, 60b), movable between a fully open position and a fully closed position to regulate the bleed airflow (66; 66a, 66b) through the bleed duct (60; 60a, 60b) based on one or more operating conditions of the gas turbine engine; a control system operably connected to the modulating valve (74; 74a, 74b) configured to command the modulating valve (74; 74a, 74b) to a selected position based on the one or more operating conditions; and one or more sensors (76, 78) disposed at the bleed duct (60; 60a, 60b) to sense the one or more operating conditions, the modulating valve (74; 74a, 74b) responsive to the one or more operating conditions sensed by the one or more sensors (76, 78), the one or more sensors (76, 78) disposed between the bleed port (58; 58a, 58b) and the modulating valve (74; 74a, 74b); wherein the one or more operating conditions are one or more properties of the bleed airflow (66; 66a, 66b) entering the bleed port (58; 58a, 58b); and wherein the one or more sensors include a pressure sensor or a temperature sensor. a compressor section; a turbine section operably connected to the compressor section; and a bleed air cooling system, including: a bleed port (58; 58a, 58b) disposed at an axial location of the gas turbine engine to divert a bleed airflow (66; 66a, 66b) from a gas turbine engine flowpath; a bleed outlet disposed at a cooling location of the gas turbine engine; a bleed duct (60; 60a, 60b) in fluid communication with the bleed port (58; 58a, 58b) and configured to convey the bleed airflow (66; 66a, 66b) from the bleed port (58; 58a, 58b) to the bleed outlet; a turbine manifold disposed between the bleed duct and the bleed outlet, the turbine manifold extending circumferentially around the turbine section to distribute bleed airflow to multiple circumferential locations of the turbine section; a modulating valve (74; 74a, 74b) disposed at the bleed duct (60; 60a, 60b), movable between a fully open position and a fully closed position to regulate the bleed airflow (66; 66a, 66b) through the bleed duct (60; 60a, 60b) based on one or more operating conditions of the gas turbine engine; a control system operably connected to the modulating valve (74; 74a, 74b) configured to command the modulating valve (74; 74a, 74b) to a selected position based on the one or more operating conditions; and one or more sensors (76, 78) disposed at the bleed duct (60; 60a, 60b) to sense the one or more operating conditions, the modulating valve (74; 74a, 74b) responsive to the one or more operating conditions sensed by the one or more sensors (76, 78), the one or more sensors (76, 78) disposed between the bleed port (58; 58a, 58b) and the modulating valve (74; 74a, 74b); wherein the one or more operating conditions are one or more properties of the bleed airflow (66; 66a, 66b) entering the bleed port (58; 58a, 58b); and wherein the one or more sensors include a pressure sensor or a temperature sensor. a bleed port (58; 58a, 58b) disposed at an axial location of the gas turbine engine to divert a bleed airflow (66; 66a, 66b) from a gas turbine engine flowpath; a bleed outlet disposed at a cooling location of the gas turbine engine; a bleed duct (60; 60a, 60b) in fluid communication with the bleed port (58; 58a, 58b) and configured to convey the bleed airflow (66; 66a, 66b) from the bleed port (58; 58a, 58b) to the bleed outlet; a turbine manifold disposed between the bleed duct and the bleed outlet, the turbine manifold extending circumferentially around the turbine section to distribute bleed airflow to multiple circumferential locations of the turbine section; a modulating valve (74; 74a, 74b) disposed at the bleed duct (60; 60a, 60b), movable between a fully open position and a fully closed position to regulate the bleed airflow (66; 66a, 66b) through the bleed duct (60; 60a, 60b) based on one or more operating conditions of the gas turbine engine; a control system operably connected to the modulating valve (74; 74a, 74b) configured to command the modulating valve (74; 74a, 74b) to a selected position based on the one or more operating conditions; and one or more sensors (76, 78) disposed at the bleed duct (60; 60a, 60b) to sense the one or more operating conditions, the modulating valve (74; 74a, 74b) responsive to the one or more operating conditions sensed by the one or more sensors (76, 78), the one or more sensors (76, 78) disposed between the bleed port (58; 58a, 58b) and the modulating valve (74; 74a, 74b); wherein the one or more operating conditions are one or more properties of the bleed airflow (66; 66a, 66b) entering the bleed port (58; 58a, 58b); and wherein the one or more sensors include a pressure sensor or a temperature sensor.