Engines APU. ENG Flashcards
What are the APUs max operating altitude limits(flight envelope)?
FL391 - max operating altitude -Generator use altitude -Start limit with normal pwr FL250 - max start limit when solely on bat. pwr FL200 - max bleed air use
Why must the aircraft batteries be on for all APU starts AND when the APU generator is the sole source available to the starter motor?
- Turning them ON permits the APU starter motor to connect to the aircraft battery buses which are the only source for the starter motor
- In the event an APU Fire when the APU generator is the sole source of power, the batteries being in ensures a pwr source for proper APU shutdown and extinguisher discharge
Uses of APU bleed air
Can and can nots?
CAN - Engine starts
A/C pack operation
CANNOT - wing anti ice
What Protection is not provided by the Full Authority Digital Control(FADEC) during inflight Engine starts?
EGT Protection is not provided
Which malfunction can the FADEC not identify therefore cannot automatically abort?
Tailpipe Fire
How does a pilot manually abort a start?
By placing the respective ENG NASTER switch to OFF
What is the effects on both FADECs when the aircraft is initially powered
Both FADECs are energized and perform a self test. After the test they deenergize. If the FADEC is not energized the engine indications are replaced with Amber Xs.
When do the FADECs reenergize after the self test
When the ENG MODE is placed to IGN START
How is the FADEC powered after engine start
Dedicated alternator
Minimum oil quantity for engine start
9.5 quartz +0.5 quart for every hour of flight
What’s the meaning of the FLAP OPEN and LOW OIL LEVEL indications on the ECAM APU page?
(Pic)
- FLAP OPEN:
A. APU air intake flap is fully
Open
B. Flap is commanded open when APU
MASTER SW pb is selected ON
C. APU starter motor is inhibited until flap
Is fully open - LOW OIL LEVEL:
A. APUs oil tank quantity is sensed to be low
B. Indication would appear immediately
When the APU MASTER SW pb is
Selected to ON and the aircraft is on
Ground - Note: with the LOW OIL LEVEL indicated, the APU START pb should not be selected ON. Contact maint.
What are the indications when the APU is on speed?
Pic
1. AVAIL (green) appears on the:
A. APU START pb
B. ECAM APU page
C. E/WDs memo section(APU AVAIL)
2. APU BLEED (green):
A. E/WDs memo section
B. Replaced APU AVAIL when the APU
Bleed valve is open
3. Note: APU generator is never indicated on the E/WD memo sectionWhat’s the function of the APU MASTER SW pb?
Pb
- ON (blue)
A. APU Computers is enabled and performs a self test
B. Air intake flap is commanded open - Light out - the APU computer is deactivated and the APU shuts down
- FAULT (Amber) - an automatic shutdown or failed start has occurred
How do you shut down the APU normally?
Selecting the APU MASTER SW to OFF(light out)
What’s the function of the APU BLEED pb and APU GEN pb?
Pic
- APU BLEED pb
- ON (blue) commands the APU bleed valve open
- APU GEN pb:
A. Light out - APU generator will auto
Energize once the APU is in speed
B. OFF (white) - APU is deenergized
How can continuous ignition (both igniters) be activated manually?
(Pic)
By rotating the ENG MODE Selector from NORM to IGN/START following an engine start
What is the indication that continuous ignition has been activated?
IGNITION (green) appears in the memo section of the E/WD and is the only indication.
What are the indications for engine igniters on the ECAM ENGINE page?
(Pic)
- During engine start, when the igniters have been energized, the igniter indication is displayed near the bottom of the ECAM ENGINE page next to the start valve indication
- Igniters are labeled A & B in green for each engine
- AB indicates that both igniters are in use(continuous ignition)
What are the indications on the E/WD N1 gauges?
Pic
- Green - digital numeric N1 speed and analog green line N1 speed
- Amber tick mark - FADEC computed maximum N1 for current ambient temperature
- Red arc - maximum permissible
- White circle - current position of the associated thrust lever
- Blue arc - indicates the difference between actual N1 and the thrust commanded by the autothrust system
- Boxed Amber REV - one or more of the reverser blocker Doors is not stowed or unlocked
- Boxed green REV - all four reverser blocker doors are fully deployed
What’s the meaning of the Grey background on the E/WD N2 page?
(Pic)
An active engine start sequence is occurring. When it is complete the Grey background disappears
What occurs when an ENG MAN START pb is selected ON?
Pic
- ON (blue) - illuminated within the pb
- The respective engine start valve opens if the ENG MODE Selector is in CRANK or IGN/START and bleed air is available
- The respective valve will auto close at 50% N2 but the ON light will remain illuminated
What is the igniter behavior during automatic and manual starts.
( Pic)
- Automatic - igniters alternate between starts(A or B)
2. Manual - both igniters are automatically activated(AB)
Describe the movement of the Amber Max EGT tick mark on the engine EGT gauge during and after engine start.
(Pic)
- During start the tick ark moves to the start EGT limit
2. When start complete the tick mark returns to the normal Maximum Continuous Thrust (MCT) EGT limits
What is the function of the controls and indicators on the ENG panel?
(Pic)
- ENG MASTER 1(2) switches -
A. ON - initiated the engines start sequence
B. OFF - shuts down the engine - ENG MODE Selector -
A. NORM - normal ops after engine start
B. IGN/START - selected prior to engine start
1. Displays the ECAM ENGINE page on
The SD with start valve indications
2. Connects FADEC to the electrical
System
3. Commands packs valves closed for
30 seconds
4. Activates continuous ignition WHEN
Cycled from the NORM position
C. CRANK - only permits the rotation of
The engine (dry crank)
1. No fuel or ignition
2. MAN START pbs must be used to open
The respective start valve - FIRE (red) - illuminates when an engine fire has been detected
- FAULT (Amber) - illuminates when
A. Auto start has been aborted (FADEC
start fault)
B. A disagreement between the actual
Position of the HP fuel valve and it’s
Commanded position
Note: there is no relationship between FIRE and FAULT indications. They are separate
What is the purpose of the Engine Interface Computer(EIC)
It collects and transmits data to the FADEC used for engine management.
When will the FADEC protect against EGT overexceedance?
Only during ground starts
FADEC electrical power is provided by?
The aircrafts electrical system when the engine is not running and by a dedicated engine driven alternator when the engine is running.
Does the FADEC detect a tailpipe fire.
No
The CRANK position on the ENG MODE Selector is used for what and with what?
- To crank the engine without allowing and fuel to be supplied to the engines
- Used with the ENG MAN START pbs to dry crank
The blue arc on the N1 indicator means what?
Represents the difference between the current thrust output and the thrust commanded by the Autothrust system.
The FADEC limits each engine start cycle to how long?
2 minutes
