Pneumatics - AMS Anti-Ice Systems Flashcards
What is the function of the Air Management System Controller, (the dual-channel, software based, electronic digital controller)?
It continuously monitors the performance of the pneumatic system components, the WHSAIS, as well as the airflow schedule of the ACS and maintains system functionality through sstem logic.
What sub-systems are considered pneumatic?
Air conditioning, cabin pressurization, wing and horizontal stab anti-ice system
How is the bleed system controlled?
By two bleen Pressure Regulating Shutoff Valves (PRSOV) located in each pylon
What are the functions of the two Pressure Regulating Shutoff Valves (PRSOVs)?
They regulate the hot bleed air released to the ECS and AIVs and provide a firewall shutoff capability for the bleed air lines.
What would expect regarding the AMC if the temperature were above 30c?
A white crew awareness EICAS message stating that one or both bleed valves has closed, which can be verified on the schematic page.
Does a PRSOV automatically close in case of a single engine takeoff condition?
Yes
Can the remaining bleed air supply all of the bleed air required by the system when in OEI condition?
Yes, via the cross bleed valve.
How can the pilot override the RH PRSOV to the closed position?
By placing the pneumatic bleed 2 toggle switch to the OFF position.
What does turning the ECS knob to OFF VENT do?
Opens the Ram Air Valve (RAV) in the rear fuselage providing fresh to both the cabin and cockpit, closes the FCSOVS and closes both PRSOVs.
What two air conditioning modes control cockpit and cabin temperature?
Auto and manual modes.
How does the crew transfer cabin temp control to the passengers?
By dialing the cabin temp knob full counter-clockwise into the detent.
How is the temperature of the air to the cabin controlled?
Temperature modulating valves (TMVs) mix cooled air from the heat exhangers with hot bleed air based on temperature selection on the cockpit control panel.
What is the function of the Vapor Cycle System?
Provides cooling air for the cabin and cockpit and is operated automatically by the ECS controller. (The VCS uses a refrigerant, evaporators, condenser and a fan to produce the cold air)
When can the VCS be operated on the ground?
With GPU power, or one engine operating.
What is used to cool the heat exchanger?
Ground cooling fan on the ground or ram air in flight.