Flashcards in Air Systems Deck (49):
Flight Deck Fan Switch controls what?
Recirc fan for flight deck.
Is flight deck fan avail in flight?
How does flight deck fan operate on ground?
- With all PACKS OFF, cabin air supplied
- With one PACK ON, fan increases flow of air (like ac in a car)
Flight Deck temp range in AUTO?
ECS Zone Reset Switch (ZONE RST)?
- Resets zone temp controller if fault has cleared
- If OVERHEAT cleared, reopens master trim air valve and FWD or AFT LLCTRSOV.
What will trigger ECS Zone SYS FAULT Light (Amber)?
- Temp zone duct overheat
- Zone Temp controller fault
- Trim Air Switch OFF
- Master trim air valve failed CLOSED
What will reset Lower Lobe Cargo conditioned air supply duct SOV's if they were closed by duct overheat?
Turning the LLCCAFR switch OFF momentarily.
LLCCAFR FWD LOW selector?
2/3 of Pack #3 conditioned air distributed to FWD LLCC. Pack #3 remains in HI FLOW during cruise.
LLCCAFR AFT LOW selector?
2/3 of Pack #2 conditioned air distributed to AFT LLCC. Pack #2 will remains in HI FLOW during cruise.
LLCCAFR BOTH LOW selector?
2/3 of Pack #3 and #2 conditioned air distributed respectively to FWD and AFT LLCC. All Packs will remain in HI FLOW during cruise.
LLCCAFR FWD HIGH selector?
All Pack #3 conditioned air distributed to FWD LLCC. All packs op in HI FLOW.
LLCCAFR AFT HIGH selector?
All Pack #2 conditioned air distributed to AFT LLCC. All packs op in HI FLOW.
AFT CARGO HT Switch OFF?
Shuts OFF aft cargo heat bleed air to compartment.
AFT CARGO HT Switch ON?
- Opens Overheat SOV to provide bleed air to compart
- Temp Control Valve OPENS/CLOSES to regulate temp
* Overheat SOV will automatically re-CLOSE for overheat protection
How many zones are air conditioned?
5 zones on MD
The 4/10 Toggle Switch is for use in what compartment only?
What are the LL Zone(s) Temp Range?
Main Deck Temp Range?
Why is AFT CARGO HEAT normally selected ON when LLCCAFR is in AFT LOW/HI?
Ensures compartment floor temp is maintained above freezing.
TRIM AIR Switch ON?
- Master Trim Air Valve OPEN
- Flight, Upper, Main Deck Trim Air Valves Op Auto
- Auto & Manual Selection of Pack Controllers Enabled
TRIM AIR Switch OFF?
- Master Trim Air Valve CLOSED
- Pack Temp Regulated to avg temp as selected by Flight Deck Temp selector in AUTO
- Cabin Temp Panel control of upper deck inhibited
- PTC A selected
- PTC B (auto and manual) inhibited
AFT CARGO HT air source?
Center section of bleed air duct.
What does MANUAL selector position of the temp controllers do?
Sets trim air valves manually.
On power up, what it target temp for flight deck and crew rest areas?
Trim air in not available to the flight deck, upper deck, main deck system if?
- Trim Air Switch OFF
- Center Section of bleed duct isolated.
How many Pack Temp Controllers (PTCs) are there?
Two - A and B
How many channels does each PTC have?
Each PTC has three channels. One for each pack.
What happens when a PTC detects a fault in pack channel?
Control is switched to other PTC.
How is pack operation for a failed PTC restored?
Push the Pack Reset Switch
What happens if a fault or overheat of a PTC is detected?
Respective pack valve closes resulting is pack shutdown.
Center duct air provided for?
- AFT CARGO HEAT
- TRIM AIR
- LL TRIM AIR
- PACK 2
- Potable Water Vacuum Air
- Main/Lower Deck Flow Through
- Smoke Detectors
Generally speaking, how is the air temp regulated in each of the 7 zones?
A modulation valve in each individual air duct allows varying amounts of trim air to mix with the conditioned air.
Do all 3 PACKS try to regulate their respective air to different temperatures?
NO. They have a common discharged temperature based on the zone demanding the lowest supply temp.
Primary flow of duct air for smoke detection system comes from which PACK?
How can we reset the LL air temp system (3)?
- LLCCAFR OFF then back ON
- ZONE RESET Switch
- Turn Temp Selector to MANUAL then back to AUTO
If TRIM AIR in not available to the flight deck, upper deck, or main deck (for the 4 reasons above) how is temperature controlled in the cabin?
- If Flight Deck Temp selector avail to PTC, packs regulated to achieve temp set by selector (65 to 85)
- If Flight Deck Temp selector not avail to PTC, packs regulate to achieve last temp set
- If last temp set unavailable to PTC, packs regulated to achieve avg flight deck temp of 75F/24C
L/R duct air provided for?
- LE Flaps
- HYD Reservoir and Pressure
- HYD Demand Pump
- PACK 1 (LH) & PACK 3 (RH)
If a duct section is isolated and L/R valve closed, how will LE flaps extend?
Isolated side will extend electrically while opposite side extends normally with available pneumatic air. There will be asymmetry until both are fully extended.
Is trim air for the LLCs supplied by controlling the Master Trim Air Valve?
- Trim air for the LLCs is provided directly from the bleed air duct.
Pack HI FLOW button logic?
ON - All PACKS in HI FLOW
OFF - PACK HI FLOW dependent on LLCCAFR
PACK RST Switch used for?
- Resets PACK fault protection system
- Restarts PACK after auto-shutdown
What happens if we turn a specific PACK selector to OFF?
- CLOSE the PACK Valve
- Extinguish SYS FAULT Light for the PACK RST Button
- Resets Pack Fault Protection
When the LLCCARF Switch is OFF, what controls PACK outlet temperature?
The flight deck, upper deck, or main deck temperature zone requiring the coolest temperature.
When the LLCCARF Switch is in FWD HI, what happens to PACK outlet temperature?
- PACK 3 maintains FWD LLC at temp set by selector
- Flight deck, upper deck, or main deck temperature zone requiring coolest temperate controls PACK outlet temperature of PACKS 1 and 2.
When the LLCCARF Switch is in AFT HI, what happens to PACK outlet temperature?
- PACK 2 maintains AFT LLC at temp set by selector
- Flight deck, upper deck, or main deck temperature zone requiring coolest temperate controls PACK outlet temperature of PACKS 1 and 3.
When the LLCCARF Switch is in LOW, what happens to PACK outlet temperature?
- Outlet temp of PACK supplying respective LLC won't be higher than outlet temperature of other 2 PACKS.
- The respective LLC temperature is regulated by closing the TRIM AIR MODULATING VALVE and supplying cooler air from the pack supplying air to the compartment or modulating the CARGO TRIM AIR VALVE to supply warmer air.
Trim Air is not available for the FWD LLC if?
- Center duct isolated
- FWD LLC zone duct overheat occurred
- FWD LLC Cargo Trim Air Valve CLOSED
If Trim Air is not available for the FWD LLC, what occurs?
- If FWD LLC Temp selector setting is avail to PTC, PACK 3 is regulated to achieve the set temp.
- If FWD LLC Temp selector setting is not avail to PTC, PACK 3 outlet temp is regulated to achieve the temp sensed when backup mode was initiated.
- If FWD LLC temperature is unavailable to the PTC, PACK 3 outlet temp is controlled to the outlet temperature sensed when backup mode was initiated.