Aircraft bleed air system and method for monitoring

A method for monitoring an aircraft bleed air system, wherein the aircraft bleed system includes a first pressure port fluidically connected to an intermediate or low pressure portion of a compressor in an aircraft engine, a second pressure port fluidically connected to a high pressure portion of the compressor;

• a first conduit having a first inlet connected to the first pressure port, an intermediate coupling and a first outlet;
• a second conduit having a second inlet coupled to the second pressure port and a second outlet coupled to the intermediate coupling of the first conduit, a high pressure valve in the second conduit, and a pressure regulating valve connected to the first outlet of the first conduit, wherein the method includes:
• detecting a pressure transient in an evolution of pressure occurring in the first conduit upstream of the pressure regulating valve and downstream while the pressure regulating valve is fully open and the high pressure valve is opened;
• determining that the pressure regulating valve functions correctly if the pressure transient is higher than a preset value;
• determining that the pressure regulating valve is damaged if the pressure transient is lower than a preset value, and
• issuing an alert of a defect in the aircraft bleed system or of a need of maintenance in the aircraft bleed system in response to the determination that the pressure regulating valve is damaged.

A method to monitor an aircraft bleed air system that includes:

• a first conduit including an inlet fluidically coupled to a low or intermediate portion of a compressor of an aircraft and an outlet connected to a pressure regulating valve;
• a second conduit including an inlet fluidically connected to a high pressure portion of the compressor and an outlet connected to an intermediate connection in the first conduit upstream of the pressure regulating valve, and a high pressure valve in the second conduit,
• wherein the method includes:
• initially maintaining the pressure regulating valve in a fully open position while the high pressure valve is closed and preventing high pressure air from the high pressure portion from entering the first conduit;
• opening the high pressure valve and thereafter adjusting the pressure regulating valve to regulate a flow of compressed air flowing from both the low or intermediate portion and the high pressure portion of the compressor to the pressure regulating valve;
• during a period in which the high pressure valve is opened and the pressure regulating valve is fully opened, monitoring an evolution of pressures in the first conduit downstream of the intermediate connection and upstream of the pressure regulating valve;
• analyzing the evolution of the pressures to determine a pressure transient during the period;
• determining that the pressure regulating valve is operating properly if the pressure transient is higher than a preset value;
• determining that the pressure regulating valve is damaged or in need of maintenance if the detected pressure transient is lower than the preset value, and
• issuing an alert of a defect or of a need of maintenance in response to the determination that the pressure regulating valve is damaged or in need of maintenance.