Flashcards in REVIEW QUESTIONS – AIR SYSTEMS Deck (23)
1. What does the BLEED TRIP OFF (amber) light indicate?
-Engine Bleed Valve has automatically closed due to over temperature (254C) or over pressure (220psi)
2. Conditions permitting, the TRIP RESET switch resets which lights?
-The BLEED TRIP OFF, AIR COND annunciator, and ZONE TEMP or PACK lights
3. How does the ISOLATION VALVE operate with its switch in AUTO?
-the valve will be closed with both engine bleed air switches on and both air- conditioning pack switched are in auto or high. With any of those in off, the valve will open
4. What precautions apply with the APU Bleed Valve when an Engine Bleed Valve is open?
-the engine bleed could backpressure the apu if the APU check valve fails
5. When does the DUAL BLEED (amber) light illuminate?
-#1 engine bleed on and APU bleed on or #2 engine bleed on with the Isolation valve open and APU bleed on
6. What does the WING-BODY OVERHEAT (amber) light indicate?
-Over heat in the left loop (#1 Engine strut cavity, left wing bleed air duct, left wing leading edge, left air conditioning pack, keel beam, aft cargo compartment, and apu cavity up to the apu bleed valve) or right loop (#2 engine strut cavity, right wing bleed air duct, right wing leading edge, and the right air conditioning pack). Temps range between 124C-155C
7. A single pack in high flow mode is capable of maintaining pressurization and acceptable temperatures throughout the aircraft up to what altitude?
-the maximum certified ceiling
8. Which Valve pneumatically modulates to control airflow into the respective Air Conditioning Pack based on air conditioning demands?
-The Pack Valve
9. When does a pack automatically switch to “high air flow?”
- With one pack not operating, the other pack automatically switches to “high air flow” in order to maintain the necessary ventilation rate.
If both engine BLEED Air Switches are OFF and the APU BLLED Air Switch is on (regardless of flap position, air/ground status, or number of packs operating)
10. How do the Recirculation Fan(s) operate with both RECIRC FAN switches in AUTO, and both PACK switches in AUTO?
-With both RECIRC FAN switches positioned to AUTO, and both PACK switches in AUTO, both Recirculation Fans operate.
11. Where do the Air Recirculation Fans draw air from?
The right Recirculation Fan pulls in air from the collector shroud in the forward cargo compartment.
The left Recirculation Fan pulls in air from the air conditioning distribution compartment.
12. What does illumination of a ZONE TEMP (amber) lights indicate?
-Duct overheat and the trim air modulating valve closes (after it cooled can be open with the trip reset) or failure of primary and secondary controls. If on recall, a failure of the primary control.
13. How do you position PACK switches when using external conditioned air?
- Pack switches OFF
14. What controls the temperature of conditioned air from an external air source?
-The external air cart itself
15. Packs produce air temperature to satisfy which zone?
-the zone that requires the most cooling.
16. What happens with a failure of the primary Flight Deck zone temperature control?
-automatic switching to the back up controller
17. What temperatures are commanded by positioning all Zone Temperature Selectors to OFF?
-Left pack 75F and right pack 65F
18. What provides an Equipment Cooling alert if an overtemperature occurs on the ground?
-Crew Call horn in the forward nose wheel well
19. What is the purpose of the Overboard Exhaust Valve (OEV)?
-controls the quantity of equipment cooling exhaust and smoke removal
20. When is the Outflow Valve Position Indicator operational?
-in all modes
21. When does the OFF SCHED DESCENT (amber) illuminate?
-When the aircraft starts to descend prior to reaching the preset cruise altitude
22. How is pressurization controlled with Cabin Pressurization Mode Selector in MAN?
-with a DC motor (powered by standby-DC) and is manually actuated by watching the cabin altitude panel