Abstract: An anti-icing system for an aircraft nacelle includes an inner duct and an outer duct. The inner duct extends through a first bulkhead between a gas turbine engine and a plenum of the nacelle. The inner duct is configured to deliver heated gases from the gas turbine engine to the plenum. The outer duct includes a first end and a second end. The outer duct circumferentially encompasses at least a portion of the inner duct on a first side of the bulkhead. At least one of the first end and the second end of the outer duct is mounted to at least one of the respective first bulkhead and a second bulkhead by a bellows forming an annular seal between the respective bulkhead and the outer duct.

Abstract: An anti-icing system for an aircraft nacelle includes an inner duct and an outer duct. The inner duct extends through a first bulkhead between a gas turbine engine and a plenum of the nacelle. The inner duct is configured to deliver heated gases from the gas turbine engine to the plenum. The outer duct includes a first end and a second end. The outer duct circumferentially encompasses at least a portion of the inner duct on a first side of the bulkhead. At least one of the first end and the second end of the outer duct is mounted to at least one of the respective first bulkhead and a second bulkhead by a bellows forming an annular seal between the respective bulkhead and the outer duct.

Abstract: An assembly is provided for a turbofan engine. This turbofan engine assembly includes a cowling, a door and an actuation mechanism configured to actuate movement of the door in response to receiving a control signal. The cowling is configured to form a compartment at least partially around a case of the turbofan engine. The cowling includes an exhaust port that is fluidly coupled with the compartment. The door is configured to at least partially open and close the exhaust port. This variable exhaust port may be opened in case increased airflow is needed through the compartment, such as when increased cooling airflow is needed through an environmental air precooler that cools compressed air for the aircraft cabin and the precooler exhausts its cooling air into the compartment.

Abstract: An assembly is provided for a turbofan engine. This turbofan engine assembly includes a cowling, a door and an actuation mechanism configured to actuate movement of the door in response to receiving a control signal. The cowling is configured to form a compartment at least partially around a case of the turbofan engine. The cowling includes an exhaust port that is fluidly coupled with the compartment. The door is configured to at least partially open and close the exhaust port. This variable exhaust port may be opened in case increased airflow is needed through the compartment, such as when increased cooling airflow is needed through an environmental air precooler that cools compressed air for the aircraft cabin and the precooler exhausts its cooling air into the compartment.