| 摘要 |
A bleed air system (110) for an aircraft and operating method. The system comprises an environmental control system (ECS) (142). The ECS has a plurality of operating modes. The ECS comprises first, second and third bleed ports (132, 134, 145), each bleed port being in fluid communication with a different pressure compressor stage, and comprising a respective valve (144, 146, 147) configured to moderate airflow from the respective bleed port (132, 134, 145). The ECS comprises a bleed air system sensor arrangement, an environmental control system controller (174), a bleed port valve controller (172) configured to determine an operating pressure required to operate the environmental control system in the selected mode, and to operate the valves (144, 146, 147) of the bleed ports (132, 134, 135) to provide the required operating pressure from the lowest pressure bleed port capable of providing the required pressure. |
