Pneumatics Flashcards
(175 cards)
1
Q
On the SD, when is GND displayed?
A
Displayed in white when the aircraft is on the ground.
2
Q
How many BMC’s are there? What happens if left or right BMC fails?
A
- 2 - If one BMC fails, the adjacent BMC takes over the monitoring of the bleed system to issue the following ECAM warnings: o Over pressure o Over temperature o Wing leak. - BMC 1 lost: (ENG 1) APU leak detection lost. - BMC 2 lost: (ENG 2) GEN 2 leak detection lost.
3
Q
During normal operation when would you expect to see the HP valve OPEN?
A
When idle. - Air is normally bled form the intermediate pressure stage (IP) of engine’s high-pressure (HP) compressor to minimize fuel penalty. - At low engine speed, when the pressure and temperature of the IP air are to low, the system bleeds air from the HP stage and maintain it at 36+/-4PSI. - An intermediate pressure check valve downstream of the IP part closes to prevent air from the HP stage from being circulated to the IP stage.
4
Q
How is the Bleed Air Temperature regulated and to what temperature?
A
- A pre-cooler downstream of the bleed valve regulates the temperature of the bleed air. - The pre-cooler is an air-to-air heat exchanger than uses cooling air bleed from the engine fan to regulate the temperature to approximately 200 degrees.
5
Q
How is the bleed air pressure regulated? What is the normal pressure?
A
- The bleed valve, which is downstream of the junction of HP and IP ducting, acts as a shut-off and pressure regulating valve. - It maintains delivery pressure at 45+/-5PSI. - May fluctuate between 38 ~ 56PSI with max peak-to-peak pressure of 16PSI) at high engine power to FL100).
6
Q
With the cross-bleed selector in AUTO, what controls the position of the crossbleed valve?
A
- 2 electric motors, one for automatic, one from manual mode, control the valve. - In automatic mode, the crossbleed value opens when the system uses APU bleed air. It closes, if the system detects an air leak, except during engine start.
7
Q
What happens if a bleed leak occurs with the crossbleed selector in AUTO?
A
It closes. Except during engine start.
8
Q
Which bleed (engine or APU) has priority?
A
APU
9
Q
Does the overhead panel FAULT light extinguish when the temperature drops following a bleed overheat?
A
The FAULT light goes out when the ENG BLEED p/b switch is OFF if the fault has disappeared.
10
Q
What happens to the fault light if the bleed air temperature drops following bleed overheat?
A
The FAULT light goes out when the ENG BLEED p/b switch is OFF if the fault has disappeared.
11
Q
When do the bleed air temperature and pressure go amber on the S.D?
A
- Pre-cooler outlet temperature overheat 290 degrees for > 5sec, 270 degrees for > 15sec, 257 degrees for > 55sec, or < 4PSI, or if overpressure detected by BMC (threshold 57-60PSI).
12
Q
Is WAI allowed if only one bleed system is operating?
A
Yes, if only one pack operating.
13
Q
What should you NOT do if GD LP Air is connected? And the HP air?
A
LP: Packs 1+2 OFF, to prevent pack contamination. HP: Do NOT use packs + APU bleed.
14
Q
Where on the aircraft can a bleed leak be detected?
A
Wings: each bleed air duct Engine pylons Aft Fuselage: area surrounding the APU bleed air duct
15
Q
What are the 2 pressure controllers and how do they switch roles?
A
- Active and standby pressurization controllers 2. Automatically: shortly after landing or If active press controller fails Manually: placing the MODE SEL push button to MAN for 10 seconds and then returning it to AUTO(lights out) mode
16
Q
In the event the flight must return to the departure airport immediately after takeoff, what pressurization system action must be taken by the pilot?
A
No action The systems “Abort mode” takes care of it automatically.
17
Q
What’s the function of each position of the X BLEED Selector? (Pic)
A
- SHUT - commands crossbleed valve closed, overriding auto logic 2. AUTO - logic controls opening and closing of the crossbleed valve A. Commanded open when the APU bleed Valve is open B. Commanded closed when APU bleed Valve is closed C. Commanded closed when a bleed leak is Detected 3. OPEN - commands crossbleed valve open, overriding auto logic.
18
Q
What are the indications of external high pressure air being applied to the pneumatic system? (Pic)
A
With NO internal air source being provided(ie. APU or engine bleed air), a PSI value is displayed on the left side of the ECAM BLEED page. By default the air source must be an external high pressure air cart
19
Q
What are the indications of the Engine Bleed Valves and HP(High Pressure) valves on the ECAM BLEED page?
A
- Engine bleed valves are depicted next to the respective engine’s number(1 and2) on lower portion on the page 2. HP valves are depicted on the lower portion of the page next to the white HP designator.
20
Q
Are IP(Intermediate Pressure) check valves depicted on the ECAM BLEED page?
A
No - they are only represented by a white IP designator. The valves are not drawn.
21
Q
What are the indications when APU bleed air is in use.
A
- APU bleed valve indicates open on the ECAM BLEED page 2. APU BLEED is presented in green on the memo section of the E/WD
22
Q
What are the ECAM indications on the ECAM COND page of a Zone Regulator channel failure? (Pic)
A
- Primary channel failure: ALTN MODE appears at top of COND page. 2. Secondary channel failure: all temperature values are replaced with Amber Xs. 3. Primary and secondary channel failure: A. PACK REG appears at top of COND page B. All temp values are replaced with Amber Xs
23
Q
What are the Indications of pack failure? What ECAM page? (Pic)
A
- Primary: A. ECAM failure message appears on E/WD memo section B. All pack information presented on the BLEED page is still present 2. Secondary: A. All temp indications for the corresponding Pack will be replaced with Amber Xs 3. Primary and secondary channel failure: A. All temp indications for corresponding pack will be replaced by Amber Xs. B. ECAM failure message appears in the E/WD memo section
24
Q
How many pressurization controllers are installed on the aircraft and where is the active system displayed on ECAM? (Pic)
A
- 2 pressurization controllers
- Designated as SYS 1 and SYS 2,
3 current active system can be viewed on the ECAM CAB PRESS page
25
What is the function of the LDG ELEV Selector? What computer does it effect? (Pic)
1. In AUTO (detention) position the FMGCs provide the pressurization system with the landing field elevation 2. Outside of AUTO (turning clockwise): A. Landing field elevation is set manually B. Used when BOTH FMCGs fail or when landing airport is not in FMS database
26
How is the LDG ELEV Selector calibrated?
In thousands not hundreds of feet
27
What is the function of the manual pressurization controls? (Pic)
1. MODE SEL pb: A. Selecting MAN(light on) enables use of the MAN V/S CTL toggle switch to manually control the outflow valve B. Deactivated the auto pressurization mode 2. MAN V/S CTL toggle switch: A. UP commandsthe outflow valve to open, Reducing cabin pressure - increasing Cabin’s altitude. “Taking the cabin up” B. DN commands the outflow valve close, Increasing cabi pressure- decreasing Cabin altitude “taking the cabin down”
28
How is the pressurization monitored? Which pages?
Performance can be monitored on either ECAM CAB PRESS or Cruise pages
29
What is the function of the DITCHING pb? (Pic)
Placing the pb to ON commands the following to close: 1. Outflow valve((if the Mode Select pb is auto) 2. Emergency ram air inlet 3. Avionics ventilation inlet valve 4. Avionics ventilation extract valve 5. Pack flow control valves (All these valves are located below the aircrafts flotation line)
30
What is the Avionics Compartment’s venting and cooling configuration that is not automatic and requires pilot action? (Pic)
1. AVIONICS SMOKE - requires to vent smoke overboard 2. Placing the BLOWER and EXTRACT pbs to OVRD(whit): A. Allows additional air conditioning to Enter the compartment B. Forces air within compartment Overboard
31
What is the indications of smoke in the avionics compartment on the ventilation penal? (Pic)
FAULT (Amber) appears on the BLOWER and EXTRACT pb
32
What 5 purposes has the Pneumatic System?
To provide compressed air as a source for: 1. Air Conditioning 2. Engine Starting 3. Wing Anti Icing 4. Water Pressurisation 5. Hydraulic Reservoir Pressurisation.
33
What are the possible sources of Pneumatic Air?
Engine Bleed APU Bleed External HP Air
34
What are BMCs and how many are there?
Bleed Monitoring Computers ( or, sometimes, Bleed Management Computers, 'Monitoring' however is the official name.) There are 2.
35
How are engine bleed valves signalled and operated?
Signalled electrically from the BMCs. Operated pneumatically by upstream (i.e. engine side) Engine Bleed Air.
36
With the engine running, will the engine bleed valve Open?
Yes it will. Unless electrically signalled Closed, or in order to prevent reverse flow.
37
What conditions will cause the BMC to signal the Bleed valve closed.
- On-side engine starting - APU Bleed valve Open - downstream Overpressure or Overheat - Leak detected (in the Onside Wing or Pylon only.)
38
What other electrical signals will cause the Engine Bleed valve to be signalled closed?
- Engine Fire p/b pressed - Engine Bleed p/b to OFF.
39
During Climb and Cruise, is Air bled from the IP or the HP stages of the engines?
IP. The HP valve is only required when IP pressure is low and will maintain Bleed Pressure to 36+\- 4 psi.
40
If the Engine Bleed valve is closed electrically, what happens to the HP Valve?
It too is electrically signalled closed.
41
To what pressure is bleed air controlled and by which component?
45+\- 5 psi. By the Engine Bleed Air Valve in its Pressure Regulating role.
42
How is Bleed Air Temperature regulated and to what temperature?
A pre-cooler uses Fan Air to reduce the temperature of the bleed air to 200 deg C.
43
How is the APU Bleed Air Valve signalled and operated?
Signalled OPEN electrically from either BMC Operated pneumatically by Upstream APU Bleed Air Pressure.
44
With the APU able to produce Bleed Air, but in the absence of any control signal, will the APU Bleed Valve open or close.
It will remain closed unless electrically signalled Open by a BMC.
45
What conditions must be fulfilled before the APU Bleed Valve is signalled open?
- Bleed Switch ON - APU speed \> 95% - No leaks ( but this is ignored during engine start. )
46
What is the effect on the pneumatic system when the APU Bleed Valve opens?
- Cross-bleed Opens ( if in AUTO) - Both Engine Bleed Valves signalled closed. Note: This action lies at the heart of Pneumatic System functionality: APU Bleed Valve Open = X-Bleed Valve Open + Engine Bleed Valves Closed APU Bleed Valve Closed = X-Bleed Valve Closed + Engine Bleed Valves Open.
47
To which side of the Pneumatic System does the APU Bleed supply connect?
The Left side.
48
In AUTO mode, APU Air in use, what will cause the X-Bleed Valve to be signalled closed?
Any leak detected (other than during engine start.)
49
Which areas on the aircraft are monitored for Pneumatic Air Leaks?
- Wing leading edge - Pylon (Engine) - APU supply duct.
50
What will be the effect of a Left Wing Leak being detected?
- FAULT light on Left Bleed p/b - Appropriate ECAM Caution - Left Engine Bleed signalled closed - APU Bleed signalled closed - X-Bleed signalled closed NB: During engine start APU & X-Bleed Valves remain open until start complete, the Engine Bleed valve is closed anyway.
51
What will be the effect of a Right Wing Leak being detected?
- FAULT light on Right Bleed p/b - Appropriate ECAM Caution - Right Engine Bleed signalled closed - X-Bleed signalled closed NB: During engine start X-Bleed Valve remains open until start complete, the Engine Bleed valve is closed anyway. APU Bleed valve is unaffected by a Right Wing Leak.
52
What is the effect of a Pylon (Engine) Leak?
- Onside Bleed Valve FAULT light & ECAM Caution ( except during engine start.) - Onside Engine Bleed Valve signalled closed - X-Bleed signalled closed.
53
What is the effect of an APU Duct Leak?
- APU Bleed p/b FAULT light (and ECAM.) - APU Bleed Valve signalled closed (except during engine start.) - X-Bleed signalled closed (except during engine start.) Note: Closure of the APU Bleed Valve will allow Engine Bleed Valves to open if Engine is running.
54
If one BMC has failed, the other will take over monitoring functions. However, what will happen to fault detection if BMC1 has failed?
Over-temperature, Overpressure of the Left Bleed Supply, & Left Wing Leak, will be detected by BMC2 and an ECAM caution will be generated. However, the FAULT light in the Left ENG Bleed p/b will not illuminate nor will the Left Engine Bleed Valve close. In addition; Neither a Left Pylon (engine) Leak nor an APU Duct Leak will be detected at all. DSC-36-10-60
55
What will happen to fault detection if BMC2 has failed?
Over-temperature or Overpressure of the Right Bleed Supply will be detected by BMC1 and an ECAM caution will be generated; However, the FAULT light in the Right ENG Bleed p/b will not illuminate nor will the Right Engine Bleed Valve close automatically. If a Right Wing Leak is detected, again, the ECAM message will be generated, but the Right ENG Bleed FAULT Light will not illuminate, nor will it close the Right ENG Bleed Valve automatically. In addition, a Right Pylon (engine) Leak will not be detected at all.
56
If a Bleed Valve FAULT light illuminates because of an Over-temperature and the Bleed Valve is switched OFF, will the FAULT light extinguish immediately?
No : only when the over temperature has disappeared.
57
What is the single meaning of the APU Bleed FAULT light?
APU Leak detected.
58
What are the positions of the X-Bleed Selector?
CLOSED AUTO OPEN
59
Which side of the X-Bleed Valve is the Ground HP Connection?
Left
60
When is the Ground HP Symbol ( a green triangle ) displayed?
Only on the ground.
61
Is it permissible to use a combination of the APU and External HP Pneumatic Air to pressurise the Pneumatic System?
No. Ref. LIM-21
62
If an ECAM AIR ENG 1 BLEED FAULT caution is generated, is it necessary to switch OFF the associated Engine Bleed Switch, and what are the consequences of this fault?
The Bleed Valve p/b is to be switched OFF only if it does not close Automatically. - ONE PACK ONLY IF WAI ON One pack must be closed when the pilot is using wing anti-ice because of pre-cooler performance.
63
If there has been a Wing or Engine Bleed Leak, what important consideration applies to the rest of the flight?
Avoid Icing Conditions
64
Is it permissible to use External HP (note HP) Air for Air Conditioning?
Only if the Air Supply is confirmed to be free of Contamination. Ref: FCOM PRO-SUP-21
65
When using External Pneumatic Power for Engine Start, which engine is started first and what is the recommended start pressure?
Engine 1 normally, but can be either. 30 psi (with the start valve open.) Ref: QRH SI 140
66
Following the first engine start from External Pneumatic Power, how is the second engine normally started?
By the Cross-bleed Engine Start Procedure.
67
When using the Cross-Bleed Engine Start Procedure; What are the positions of the 4 Pneumatic System Valves? What is the minimum recommended pneumatic pressure prior to start valve opening? What maximum N2 must be observed?
APU Bleed - OFF Engine Bleed Valves: Running Engine - ON, Receiving Engine - OFF. X-Bleed Valve - OPEN. Minimum Pressure prior to start : 30 psi Maximum N2 : 80% Ref: QRH SI 150
68
The engines are the primary source of compressed air in flight. Where is air bled from in the CFM engine?
IP air is bled from the 5th stage of the engine High Pressure compressor. HP air is bled from the 9th stage of engine High Pressure compressor.
69
In flight the APU can be used to supply bleed air to user systems up to what altitude?
20,000 feet.
70
Where does the pneumatic system get its electrical power?
The DC system of the aircraft.
71
Where are the BMCs installed?
In the avionics compartment.
72
In normal flight BMC2 is powered by...?
DC2 It is unpowered in the emergency electrical config.
73
On ECAM Bleed Page. What does Cross-Bleed Valve in-line amber indicate?
The Cross-Bleed valve is not in the commanded (open) position.
74
On the overhead panel, an amber fault light on the APU Bleed push button indicates?
BMC1 has detected an APU Leak.
75
The engine bleed valve maintains what delivery pressure?
45 psi +/- 5 psi
76
What is the design of the bleed air leak detection system?
A single loop for the APU & pylon. A double loop for the wing.
77
What happens to the cross-bleed valve if a BMC detects a leak in the bleed air system?
The cross-bleed valve will close, except during engine start.
78
Within the engine bleed system, the Overpressure Valve will close when the bleed air pressure exceeds... ?
85 psi
79
Where is the pre-cooler located on the engine bleed system?
Downstream of the Overpressure Valve.
80
If both BMCs are faulty, ECAM will read; "BLEED MONITORING FAULT" and this will be accompanied by ... ?
No master caution & no aural warning.
81
If BMC2 fails, BMC1 takes over automatically but ... ?
The ENG2 BLEED LEAK warning is lost, although The APU BLEED LEAK warning remains available.
82
A leak in the APU Bleed System would be detected by ... ?
BMC1 only
83
Above what N speed is bleed air usually available from the APU?
N \> 95% (+2 seconds)
84
How does the X BLEED work when selected to AUTO?
Opens the X BLEED valve if APU valve is open Closes the X BLEED valve if APU bleed valve is closed, or an air leak is detected.
85
What happens to the X BLEED valve if the APU FIRE button is pushed?
The X BLEED valve will close.
86
Turning ON the ENG BLEED switch will open the bleed valve when?
- Upstream pressure is \> 8 psi - APU BLEED switch is OFF or APU bleed valve closed - There is no leak, over-pressure or over-temperature detected - ENG FIRE switch is not released out - Engine start valve is closed.
87
1. (DSC-36-10) With engines and Apu running and Apu bleed valve selected on, select the correct statement : (a) Engine bleed valves open, X bleed valve opens, Apu bleed valve closes. (b) Engine bleed valves close, X bleed valve opens, Apu bleed valve opens. (c) Engine bleed valves open, X bleed valve closes, Apu bleed valve opens. (d) Engine bleed valves close, X bleed valve closes, Apu bleed valve opens.
(b) Engine bleed valves close, X bleed valve opens, Apu bleed valve opens.
88
2. (PRO-SUP-70) To start an engine with external pneumatic power, the following switching is required (a) Engine bleeds off and Pneumatic X bleed to auto (b) Engine and APU bleeds off, Pneumatic X bleed open (c) Engine bleed switches off. (d) Apu bleed switch off.
(b) Engine and APU bleeds off, Pneumatic X bleed open
89
3. (DSC-36-10) Air bleed from the engines is: (a) Not cooled prior to being used by the systems. (b) Cooled in a heat exchanger by cooling air bleed from the fan section. (c) Cooled using ambient air. (d) Only cooled in the air-conditioning part.
(b) Cooled in a heat exchanger by cooling air bleed from the fan section.
90
4. (DSC-36-10) High pressure air is supplied from: (a) Engine 1 and 2 bleed systems, Apu load compressor, and HP ground connection. (b) Engine 1 and 2 bleed systems. (c) Engine 1 and 2 bleed systems and Apu load compressor. (d) Engine 1 and 2 bleed systems and the Ram Air Turbine.
(a) Engine 1 and 2 bleed systems, Apu load compressor, and HP ground connection.
91
5. (DSC-36-10) Pneumatic system operation is controlled and monitored by : (a) One bleed monitoring computer. (b) Two bleed valve computers. (c) Two bleed monitoring computers. (d) Three bleed valve computers.
(c) Two bleed monitoring computers.
92
6. (DSC-36-10) Which source operates the bleed valve : (a) Pneumatic. (b) Electric. (c) Both. (d) Hydraulic.
(a) Pneumatic.
93
7. (DSC-36-10) What happens when pressure and temperature are not sufficient to supply the corresponding engine bleed valve; (a) I P valve closed. (b) H P valve opened, I F stage closed. (c) H P valve opened, I P stage remains in the same configuration. (d) X bleed valve open, if switch in auto position.
(c) H P valve opened, I P stage remains in the same configuration.
94
8. (DSC-36-20) Can you control the H P valve position through the air bleed cockpit panel; (a) Yes. (b) No. (c) Yes, directly by turning up the pack temperature. (d) Yes, directly by turning down the pack temperature.
(b) No.
95
9. (DSC-36-20) If the bleed valve closes, the HP valve : (a) Opens automatically. (b) Closes automatically. (c) Must be manually closed by putting the pack off. (d) Fails open.
(b) Closes automatically.
96
10. (DSC-36-10) Temperature regulation is achieved by the precooler which regulates and limits the temperature at: (a) 150 deg.c. (b) 85 deg.c. (c) 200 deg.c. (d) 950 deg.c.
(c) 200 deg.c.
97
11. (DSC-36-10) Which source controls the X bleed valve : (a) Pneumatic. (b) Electric. (c) Hydraulic. (d) PTU on/off switch.
(b) Electric.
98
12. (DSC-36-10) Crossbleed valve is provided with two electric motors : (a) One for the automatic mode, the other for the manual mode. (b) Two for the automatic mode. (c) Two for the manual mode. (d) One for on ground operation, the other for in flight operation.
(a) One for the automatic mode, the other for the manual mode.
99
What are the possible sources of Pneumatic Air?
Engine Bleed APU Bleed External HP Air
100
What are BMCs and how many are there?
Bleed Monitoring Computers ( or, sometimes, Bleed Management Computers, 'Monitoring' however is the official name.) There are 2.
101
How are engine bleed valves signalled and operated?
Signalled electrically from the BMCs. Operated pneumatically by upstream (i.e. engine side) Engine Bleed Air.
102
With the engine running, will the engine bleed valve Open?
Yes it will. Unless electrically signalled Closed, or in order to prevent reverse flow.
103
What conditions will cause the BMC to signal the Bleed valve closed.
- On-side engine starting - APU Bleed valve Open - downstream Overpressure or Overheat - Leak detected (in the Onside Wing or Pylon only.)
104
What other electrical signals will cause the Engine Bleed valve to be signalled closed?
- Engine Fire p/b pressed - Engine Bleed p/b to OFF.
105
During Climb and Cruise, is Air bled from the IP or the HP stages of the engines?
IP. The HP valve is only required when IP pressure is low and will maintain Bleed Pressure to 36+\- 4 psi.
106
If the Engine Bleed valve is closed electrically, what happens to the HP Valve?
It too is electrically signalled closed.
107
To what pressure is bleed air controlled and by which component?
45+\- 5 psi. By the Engine Bleed Air Valve in its Pressure Regulating role.
108
How is Bleed Air Temperature regulated and to what temperature?
A pre-cooler uses Fan Air to reduce the temperature of the bleed air to 200 deg C.
109
How is the APU Bleed Air Valve signalled and operated?
Signalled OPEN electrically from either BMC Operated pneumatically by Upstream APU Bleed Air Pressure.
110
With the APU able to produce Bleed Air, but in the absence of any control signal, will the APU Bleed Valve open or close.
It will remain closed unless electrically signalled Open by a BMC.
111
What conditions must be fulfilled before the APU Bleed Valve is signalled open?
- Bleed Switch ON - APU speed \> 95% - No leaks ( but this is ignored during engine start. )
112
What is the effect on the pneumatic system when the APU Bleed Valve opens?
- Cross-bleed Opens ( if in AUTO) - Both Engine Bleed Valves signalled closed. Note: This action lies at the heart of Pneumatic System functionality: APU Bleed Valve Open = X-Bleed Valve Open + Engine Bleed Valves Closed APU Bleed Valve Closed = X-Bleed Valve Closed + Engine Bleed Valves Open.
113
To which side of the Pneumatic System does the APU Bleed supply connect?
The Left side.
114
In AUTO mode, APU Air in use, what will cause the X-Bleed Valve to be signalled closed?
Any leak detected (other than during engine start.)
115
Which areas on the aircraft are monitored for Pneumatic Air Leaks?
- Wing leading edge - Pylon (Engine) - APU supply duct.
116
What will be the effect of a Left Wing Leak being detected?
- FAULT light on Left Bleed p/b - Appropriate ECAM Caution - Left Engine Bleed signalled closed - APU Bleed signalled closed - X-Bleed signalled closed NB: During engine start APU & X-Bleed Valves remain open until start complete, the Engine Bleed valve is closed anyway.
117
What will be the effect of a Right Wing Leak being detected?
- FAULT light on Right Bleed p/b - Appropriate ECAM Caution - Right Engine Bleed signalled closed - X-Bleed signalled closed NB: During engine start X-Bleed Valve remains open until start complete, the Engine Bleed valve is closed anyway. APU Bleed valve is unaffected by a Right Wing Leak.
118
What is the effect of a Pylon (Engine) Leak?
- Onside Bleed Valve FAULT light & ECAM Caution ( except during engine start.) - Onside Engine Bleed Valve signalled closed - X-Bleed signalled closed.
119
What is the effect of an APU Duct Leak?
- APU Bleed p/b FAULT light (and ECAM.) - APU Bleed Valve signalled closed (except during engine start.) - X-Bleed signalled closed (except during engine start.) Note: Closure of the APU Bleed Valve will allow Engine Bleed Valves to open if Engine is running.
120
If one BMC has failed, the other will take over monitoring functions. However, what will happen to fault detection if BMC1 has failed?
Over-temperature, Overpressure of the Left Bleed Supply, & Left Wing Leak, will be detected by BMC2 and an ECAM caution will be generated. However, the FAULT light in the Left ENG Bleed p/b will not illuminate nor will the Left Engine Bleed Valve close. In addition; Neither a Left Pylon (engine) Leak nor an APU Duct Leak will be detected at all. DSC-36-10-60
121
What will happen to fault detection if BMC2 has failed?
Over-temperature or Overpressure of the Right Bleed Supply will be detected by BMC1 and an ECAM caution will be generated; However, the FAULT light in the Right ENG Bleed p/b will not illuminate nor will the Right Engine Bleed Valve close automatically. If a Right Wing Leak is detected, again, the ECAM message will be generated, but the Right ENG Bleed FAULT Light will not illuminate, nor will it close the Right ENG Bleed Valve automatically. In addition, a Right Pylon (engine) Leak will not be detected at all.
122
If a Bleed Valve FAULT light illuminates because of an Over-temperature and the Bleed Valve is switched OFF, will the FAULT light extinguish immediately?
No : only when the over temperature has disappeared.
123
What is the single meaning of the APU Bleed FAULT light?
APU Leak detected.
124
What are the positions of the X-Bleed Selector?
CLOSED AUTO OPEN
125
Which side of the X-Bleed Valve is the Ground HP Connection?
Left
126
When is the Ground HP Symbol ( a green triangle ) displayed?
Only on the ground.
127
Is it permissible to use a combination of the APU and External HP Pneumatic Air to pressurise the Pneumatic System?
No. Ref. LIM-21
128
If an ECAM AIR ENG 1 BLEED FAULT caution is generated, is it necessary to switch OFF the associated Engine Bleed Switch, and what are the consequences of this fault?
The Bleed Valve p/b is to be switched OFF only if it does not close Automatically. - ONE PACK ONLY IF WAI ON One pack must be closed when the pilot is using wing anti-ice because of pre-cooler performance.
129
If there has been a Wing or Engine Bleed Leak, what important consideration applies to the rest of the flight?
Avoid Icing Conditions
130
Is it permissible to use External HP (note HP) Air for Air Conditioning?
Only if the Air Supply is confirmed to be free of Contamination. Ref: FCOM PRO-SUP-21
131
When using External Pneumatic Power for Engine Start, which engine is started first and what is the recommended start pressure?
Engine 1 normally, but can be either. 30 psi (with the start valve open.) Ref: QRH SI 140
132
Following the first engine start from External Pneumatic Power, how is the second engine normally started?
By the Cross-bleed Engine Start Procedure.
133
When using the Cross-Bleed Engine Start Procedure; What are the positions of the 4 Pneumatic System Valves? What is the minimum recommended pneumatic pressure prior to start valve opening? What maximum N2 must be observed?
APU Bleed - OFF Engine Bleed Valves: Running Engine - ON, Receiving Engine - OFF. X-Bleed Valve - OPEN. Minimum Pressure prior to start : 30 psi Maximum N2 : 80% Ref: QRH SI 150
134
The engines are the primary source of compressed air in flight. Where is air bled from in the CFM engine?
IP air is bled from the 5th stage of the engine High Pressure compressor. HP air is bled from the 9th stage of engine High Pressure compressor.
135
In flight the APU can be used to supply bleed air to user systems up to what altitude?
20,000 feet.
136
Where does the pneumatic system get its electrical power?
The DC system of the aircraft.
137
Where are the BMCs installed?
In the avionics compartment.
138
In normal flight BMC2 is powered by...?
DC2 It is unpowered in the emergency electrical config.
139
On ECAM Bleed Page. What does Cross-Bleed Valve in-line amber indicate?
The Cross-Bleed valve is not in the commanded (open) position.
140
On the overhead panel, an amber fault light on the APU Bleed push button indicates?
BMC1 has detected an APU Leak.
141
The engine bleed valve maintains what delivery pressure?
45 psi +/- 5 psi
142
What is the design of the bleed air leak detection system?
A single loop for the APU & pylon. A double loop for the wing.
143
What happens to the cross-bleed valve if a BMC detects a leak in the bleed air system?
The cross-bleed valve will close, except during engine start.
144
Within the engine bleed system, the Overpressure Valve will close when the bleed air pressure exceeds... ?
85 psi
145
Where is the pre-cooler located on the engine bleed system?
Downstream of the Overpressure Valve.
146
If both BMCs are faulty, ECAM will read; "BLEED MONITORING FAULT" and this will be accompanied by ... ?
No master caution & no aural warning.
147
If BMC2 fails, BMC1 takes over automatically but ... ?
The ENG2 BLEED LEAK warning is lost, although The APU BLEED LEAK warning remains available.
148
A leak in the APU Bleed System would be detected by ... ?
BMC1 only
149
Above what N speed is bleed air usually available from the APU?
N \> 95% (+2 seconds)
150
How does the X BLEED work when selected to AUTO?
Opens the X BLEED valve if APU valve is open Closes the X BLEED valve if APU bleed valve is closed, or an air leak is detected.
151
What happens to the X BLEED valve if the APU FIRE button is pushed?
The X BLEED valve will close.
152
Turning ON the ENG BLEED switch will open the bleed valve when?
- Upstream pressure is \> 8 psi - APU BLEED switch is OFF or APU bleed valve closed - There is no leak, over-pressure or over-temperature detected - ENG FIRE switch is not released out - Engine start valve is closed.
153
What 5 purposes has the Pneumatic System?
To provide compressed air as a source for: 1. Air Conditioning 2. Engine Starting 3. Wing Anti Icing 4. Water Pressurisation 5. Hydraulic Reservoir Pressurisation.
154
Which failure in the bleed system causes an ECAM warning?
Overpressure overtemperature and wing leak.
155
How does the bleed pressure regulation work?
The bleed valve which is downstream of the junction of HP (high pressure) and IP (intermediate pressure) ducting acts as a shut-off and pressure regulating valve. It maintains delivery pressure at 45 +/- 5 psi.
156
How does the bleed temperature regulation work?
A precooler downstream of the bleed valve regulates the temperature of the bleed air. The precooler is an air-to air heat exchanger that uses cooling air bleed from the engine fan to regulate the temperature to approximately 200°C.
157
Which systems or components are supplied by high pressure air?
Air conditioning engine starting wing anti-ice water pressurization and hydraulic reservoir pressurization.
158
Pneumatic system operation is controlled and monitored by...
Two Bleed Monitoring Computers (BMC).
159
What are the high pressure air sources?
Engine bleed systems APU load compressor and HP ground connection.
160
What is the function of the crossbleed valve?
The crossbleed valve on the crossbleed duct allows the air supply systems of two engines to be isolated or interconnected.
161
What occurs if one Bleed Monitoring Computer (BMC) fails?
If one BMC fails the other one takes over most of the monitoring functions.
162
On which ECAM page you will get information about the PNEUMATIC system?
BLEED page.
163
How does the APU bleed valve work?
The APU bleed valve operates as a shut-off valve to control APU bleed air. It is electrically controlled and pneumatically operated.
164
How does the bleed leak detection work?
Leak detection loops detect any overheating near the hot air ducts in the fuselage pylons and wings. For the pylon and APU the sensing elements are tied to form a single loop and for the wing a double loop.
165
What does the amber "FAULT" light in the APU BLEED pushbutton indicate?
Bleed leak (APU Bleed valve closes)
166
What logic control the X-Bleed valve when the X-BLEED switch is in auto?
- When APU valve is open, the x-bleed valve is open - When APU bleed valve is closed, the x-bleed valve is closed - X-bleed also closes for wing, pylon, or APU duct leak (Except during engine start)
167
If the APU is running, is it necessary to manually select APU BLEED OFF prior to APU shutdown?
No. When the APU MASTER sw is selected OFF, the bleed air valve is closed and the APU is allowed to cool prior to shutdown
168
The pneumatic system is monitored and controlled by?
2 Bleed Monitored Computers (BMC)
169
If one BMC fails, can the other take over?
Yes, they are interconnected. If one BMC fails: - APU and ENG 1 leak detections are not monitored - ECAM APU BLEED LEAK warning is lost
170
On the ECAM Bleed page, how do you tell if the GND HP air supply is connected?
The GND unit temperature and pressure are indicated on the ECAM BLEED PRECOOLER 1
171
How can you tell if the GND LP air supply is removed before selecting the APU BLEED pushbutton to on?
Turn off the CAB FANS pushbutton, open the air vent on the instrument panel and confirm no airflow.
172
What flow rate is automatically selected when APU bleed air is in use or during single pack operation?
HI
173
If the engine bleed air in-flight is too low, what will occur?
Engine speed is automatically increased to provide adequate bleed air pressure
174
After engine start with the APU BLEED pushbutton ON, what source is supplying bleed air to the packs?
APU Bleed
175
What does an amber "FAULT" light in the APU BLEED pushbutton indicate?
An APU bleed leak
