Fuel System Flashcards
Each INNER tank contains one collector cell that:
- Maintains a FUEL RESERVOIR for the ____ ____ pumps and
- Provides ____ _ protection to feed the engines.
- Is maintained and contains about ____ of fuel.
Each INNER tank contains one collector cell that:
1. Maintains a FUEL RESERVOIR for the FUEL BOOSTER pumps and
2. Provides NEGATIVE G protection to feed the engines.
3. Is maintained full and contains about 1,000 kg of fuel.
Each inner tank is divided into ____ ____ via a SPLIT valve that normally remains ____.
Each inner tank is divided into TWO PARTS via a SPLIT valve that normally remains OPEN.
The inner tank is used as a ____ tank and, if tank damage is suspected (i.e. FQI data is lost or there is a rapid FQI decrease following an engine failure), the SPLIT valve can be ____ closed by using the dedicated pushbutton on the overhead panel.
The inner tank is used as a SINGLE tank and, if tank damage is suspected (i.e. FQI data is lost or there is a rapid FQI decrease following an engine failure), the SPLIT valve can be MANUALLY closed by using the dedicated pushbutton on the overhead panel.
When split valves are closed, the fuel contained in the ____ section of ____tanks is still usable via the ____ pumps.
When split valves are closed, the fuel contained in the AFT section of INNER tanks is still usable via the STANDBY pumps.
(Think what is “abnormal”? AFT section & SBY pumps.)
Vent surge tank locations
In each wing outboard of the outer tank, and on the right of the THS trim tank
Overpressure protector
- Wing surge tanks
- Trim surge tank
- Between the centre and the right inner tanks.
The FCMC’s…
- Measure the ____ ____ and indicate it on the ____.
- Calculate the aircraft’s ____ ____ and ____ __ ____, based on the ____ ____ ____ and the ____ __ ____ entered by the crew.
- Controls ____ __ ____ to the ____ ____ for engine feed.
- Controls ____ __ ____ to and from the ____ ____ for CG control.
- Measure the fuel quantity and indicate it on the ECAM.
- Calculate the aircraft’s Gross Weight and Center of gravity, based on the Zero Fuel Weight and the CG entered by the crew.
- Controls transfer of fuel to the inner tanks for engine feed.
- Controls transfers of fuel to and from the trim tank for CG control.
Fuel is always fed to the engines from the ____ ____.
Fuel is always fed to the engines from the INNER TANKS.
Explain the fuel feed and transfer system:
-
CENTRE to INNERS.
- Auto TX cycles fuel between FULL and 2 000 kg below full
- Inners empty down to 4 000 kg. -
TRIM to INNERS.
- Auto TX forward and aft to optimise CG
- Inners empty down to 3 500 kg. -
OUTERS to the INNERS.
- Auto TX cycles fuel between 3 500 kg and 4 000 kg.
Fuel Used (Per Engine) - Two amber bars
Error >136 kg
Fuel Used Total - Two amber bars
When either “engine fuel used” is crossed
Fuel Quantity Indication (per tank) - Two amber bars on the last two digits
The fuel quantity is inaccurate.
FQI (tank) - Partial amber box
15T of centre tank unusable
Fuel Quantity Indication (trim or outer tanks only) - Amber box
Fuel unusable
Fuel Quantity Indication - Amber
(inner tanks only)
Low level or overflow
Fuel Quantity Indication - Pulsing quantity
Imbalance >3,000kg (left and right wing tanks)
Collector Cell Fuel Quantity - Two amber bars on the last two digits
(think collect, like ATO collects info which is….)
Quantity is inaccurate
Fuel On Board (Upper ECAM) - Amber lines last two digits
Quantity inaccurate
Gross Weight - Two amber bars on the last two digits
FQI inaccurate
Gross Weight - Blue dashes
GW not computed on ground
Centre of Gravity - Red
FMGEC (FE part) detects an excess aft CG
Centre of Gravity - Blue dashes
CG not computed on ground
ENGINE LP VALVES - In line - Green
Valve is open.
ENGINE LP VALVES - In line - Amber
Valve is abnormally open.
ENGINE LP VALVES - Cross line - Amber
Valve is closed.
ENGINE LP VALVES - Transit - Amber
Valve is in transit.
ENGINE FEED PUMPS - Cross line - Amber
Pump not running.
(line across the pump = not running)
OUTER TO INNER transfer - ▹ Green
Normal transfer (auto).
Outer tank inlet valve controls transfer by cycling inner tank contents between 3,500 and 4,000 kg
OUTER TO INNER & CENTRE TO INNER TRANSFER - ▸ Green
Manual transfer
OUTER TO INNER & CENTRE TO INNER TRANSFER - ▸ Amber
Abnormal transfer.
TRIM TANK ISOLATION INDICATION - In line - Green
One valve is open.
TRIM TANK ISOLATION INDICATION - In line - Amber
One valve is abnormally open.
TRIM TANK ISOLATION INDICATION - Cross line - Amber
Both valves are abnormally closed.
TRIM TO INNER TRANSFER INDICATION - Unshaded Green
Normal aft or forward transfer.
TRIM TO INNER TRANSFER INDICATION - Amber
Abnormal aft or forward transfer (solid amber)
APU LP VALVE INDICATION - APU (White) ▿ (White)
Valve is closed.
APU LP VALVE INDICATION - APU (White) ▿ (Green)
Fuel provided to the APU.
APU LP VALVE INDICATION - APU (Amber) ▾ (Amber)
Failed open.
APU LP VALVE INDICATION - APU (amber)
Failed closed.
X-FEED VALVE - Cross line - Amber
Valve is abnormally closed.
Fuel on Board
(Upper ECAM) - Green
The fuel quantity is accurate.
Fuel on Board
(Upper ECAM) - Partial amber box
partially usable
Fuel on Board
(Upper ECAM) - Two amber bars on the last two digits
FQI is inaccurate
MEMO - FUEL X FEED
This memo appears in green when the crossfeed valve is open
(automatically or manually). It becomes amber during takeoff (flight phases 3, 4 and 5).
MEMO - OUTR TK XFR
Outer tank transfer valve controls the transfer by cycling the associated inner tanks contents between 3 500 kg and 4 000 kg.
When each outer tank has been empty for 5 min, its outer tank transfer valves close.
MEMO - OUTR TK XFRD
This memo appears in green when the outer tank has been emptied following a transfer into the inner tank.
(Inner tanks contents cycled between 3 500 kg and 4 000 kg)
MEMO - REFUEL IN PROCESS
This memo appears in green, in flight phases 1 and 10, if the refuel panel switches are not set in the appropriate position for flight.
MEMO - REFUEL PNL
This memo appears in amber in flight phase 2 (after engine start), if the refuel panel or the cockpit refuel pb are not set in the appropriate position for flight.
MEMO - T TK XFRD
GREEN - trim tank has been emptied following a forward transfer.
Forward fuel transfer stops, when:
- The computed CG = Target CG -0.5 %.
- Inner reaches 5 000 kg
MEMO - TRIM TK XFR
GREEN - appears during trim tank transfer.
‐ Landing gear is retracted.
‐ Slats are retracted.
‐ Trim tank is not full.
‐ Inner tank above 6 250 kg.
‐ Above FL 255.
‐ CG is not on target.
CENTER TO INNER TANK TRANSFER
Each ___ ___ inlet valve controls the transfer by cycling its inner tank contents between full and approximately ____ kg below full.
Each INNER TANK inlet valve controls the transfer by cycling its inner tank contents between full and approximately 2 000 kg below full.
CENTER TO INNER TANK TRANSFER
When the ____ ____ is empty, both center tank pumps temporarily stop, and both inner tank inlet valves close.
When the CENTRE TANK is empty, both center tank pumps temporarily stop, and both inner tank inlet valves close.
OUTER TO INNER TANK TRANSFER
The outer tank fuel is transferred to the inner tanks by ____.
The outer tank fuel is transferred to the inner tanks by GRAVITY.
OUTER TO INNER TANK TRANSFER
Each outer tank transfer valve controls the transfer by cycling the associated inner tanks contents between ____ and ____.
Each outer tank transfer valve controls the transfer by cycling the associated inner tanks contents between 3 500 kg and 4 000 kg.
OUTER TO INNER TANK TRANSFER
When each outer tank has been empty for __ min, its outer tank transfer valves close.
When each outer tank has been empty for 5 min, its outer tank transfer valves close.
CENTER TO INNER TANK TRANSFER
Transfer from the center to inner tanks can be manually selected with the ___ __ ___pb. When selected ___, the inner tank inlet valves are opened and the CTR TK pumps run.
Transfer from the center to inner tanks can be manually selected with the CTR TK XFR pb. When selected MAN, the inner tank inlet valves are opened and the CTR TK pumps run.
CENTER TO INNER TANK TRANSFER (manual)
The CTR TK pumps must be selected OFF, when the:
‐ Inner tanks are ___, to manually prevent inner tank overflow.
‐ Center tank is ___
The CTR TK pumps must be selected OFF, when the:
‐ Inner tanks are FULL, to manually prevent inner tank overflow.
‐ Center tank is EMPTY
CENTER TO INNER TANK TRANSFER (manual)
When the fuel quantity of each inner tank is below ____ kg, all center tank fuel can be transferred without any risk of ____.
When the fuel quantity of each inner tank is below 17 000 kg, all center tank fuel can be transferred without any risk of OVERFLOW.
What calculates the aircraft’s CG?
The Fuel Control and Monitoring Computer (FCMC)
What is the most AFT CG target and at which weight?
39% MAC at 168,000 kg (max ZFW)
What is the FCMC desired CG range?
36.9% to 39% MAC
In flight, the FCMC only starts an AFT fuel transfer, when all of the following conditions are met:
- Gear retracted.
- Slats retracted.
- Trim tank not full.
- Inner tanks > 6 250 kg.
- > FL 255.
- CG not on target.
An aft transfer stops when the :
CHIT-MAI
- CG = Target -0.5 % , or
- Trim tank high level sensor wet, or
- Inners 6 250 kg, or
- T TANK MODE pushbutton is set to FWD, or
- Manual transfer from centre or outers to inners, or
- Automatic transfer from centre to inners.
- Inners unbalanced by > 500 kg
(The transfer will stop on the lightest side, and related aft transfer valve will automatically close until fuel balance is restored).
Normally, only one aft fuel transfer occurs per flight. However, if the CG in cruise is ahead of the target by more than ___ % , and the trim tank quantity is below ____ kg, an additional aft transfer will occur.
Normally, only one aft fuel transfer occurs per flight. However, if the CG in cruise is ahead of the target by more than 2 % , and the trim tank quantity is below 3 000 kg, an additional aft transfer will occur.
What is the maximum fuel capacity?
Approx 110,000 kg.
- Centre & Inners 33 T each
- Outers 3 T each
- Trim tank 5 T
Describe the fuel transferring from the trim tank?
FCMC moves fuel to achieve optimum CG to reduce drag during flight.
- 1 x AFT transfer during climb to target - 0.5%
- Fuel burn causes AFT CG movement
- When at AFT target (AFT limit -2.0%), FWD transfer moves CG to FWD target - 0.5%.
- Process starts again.
FWD APU PUMP FEED
The APU is fed from the Engine 1 ____ ___ (in the left inner tank) through the ____ ____ pump and the ____ ____ valve when :
The APU is fed from the Engine 1 COLLECTOR CELLS (in the left inner tank) through the APU FWD pump and the APU ISOL valve when :
‐ On the ground after 2 min (except during trim tank refuelling), or
‐ In flight below FL 255, or
‐ In flight above FL 255, when the trim tank is empty. In this case, the AFT APU pump is not running.
The APU is supplied with fuel through the ____ ____ ____ line.
The APU is supplied with fuel through the TRIM TANK TRANSFER line.
AFT APU PUMP FEED
The APU is fed from the** trim pipe** :
‐ The first two minutes when on the ground, or
‐ During trim tank refueling or,
‐ During an aft transfer.
The APU is fed from the trim tank :
‐ In flight above FL 255, as long as the trim tank is not empty, or
‐ During a forward transfer.
In the above cases, the :
‐ AFT APU pump is running.
‐ FWD APU pump is not running.
‐ APU ISOL valve is closed.
Note: The AFT APU pump will automatically start, in the event of FWD APU pump failure.
L/R/STBY fuel pumps - FAULT light
Delivered pressure drops, and
ECAM: FUEL RIGHT/LEFT/STBY PUMP 1(2) LO PR
CTR fuel pumps - FAULT light
The amber light and the ECAM caution come on, when:
PTI 17x2
‐ The delivery pressure drops, or
‐ The trim pipe ISOL valve is failed open, or
‐ Inners > 17 000 kg and either:
1) Require a manual transfer from the center tank is required or
2) One outer or inner inlet valve is failed open
T TANK MODE selector - FAULT light
(T tank is “EFFd”)
The amber light and the ECAM caution come on when:
‐ Excess AFT CG, based on the THS position (independent of fuel quantity), OR
‐ The FCMC is unable to carry out the forward transfer, OR
‐ The FUEL LO TEMP warning is triggered.
CTR & OUTER TANK XFR - FAULT light
The amber light and the ECAM caution come on when:
‐ The inner tank low level reached and the center/outer tank not empty, or
‐ The FCMC is unable to carry out the transfer to the inner tanks.
- Outer: Fuel Lo Temp
OUTR TK XFR - FAULT light
The amber light, and the ECAM caution come on, when:
‐ The inner tank low level reached and the outer tanks not empty, or
‐ The FCMC is unable to carry out the transfer to the inner tanks, or
‐ The FUEL LO TEMP warning is triggered.
Commonality between FAULT lights for both CTR and OUTR TK XFR?
Both indicate the inner tank low level has been reached and either the outer or centre tanks are not empty… OR
FCMC can’t carry out the transfer to the inner tanks.
Remember, the inner tanks feed to the engine…..
Which FAULT lights have an associated LO TEMP condition?
OUTR TK XFR and T TANK MODE..
(They’re both at the extremities so get cold fuel…)
CENTER TO INNER TANK TRANSFER
- Inner tank inlet valve controls the transfer by cycling its inner tank contents between full and approximately 2 000 kg below full.
- When the center tank is empty, both center tank pumps temporarily stop, and both inner tank inlet valves close.
What are the fuel thresholds for trim tank fuel?
36.5 T, 40 T and 76 T
36.5 T - starts filling
40 T - 2 400 kg
76 T - increases from 2 400 kg
