ATR 42-500/72-212A (PWC PW120) B1.1 and B2 (Subcategories) PDF

ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC TRAINING MANUAL ATR 42-500/72-212A (PWC PW120) B1.1 AND B2 (SUB-)CATEGORIES 36. PNEUMATIC...

ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC TRAINING MANUAL ATR 42-500/72-212A (PWC PW120) B1.1 AND B2 (SUB-)CATEGORIES 36. PNEUMATIC (ATA 36) (Level 3) ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 1 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC THIS PAGE IS INTENTIONALLY LEFT BLANK ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 2 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC TABLE OF CONTENTS 36-00 PNEUMATIC......................................................................................... 5 GENERAL DESCRIPTION.......................................................................... 5 COCKPIT PANELS ON ATR 500 SERIES................................................. 7 INTERFACES.............................................................................................. 8 FEATURES................................................................................................. 9 PNEUMATIC SAFETY PRECAUTIONS DURING MAINTENANCE........ 13 36-10 DISTRIBUTION................................................................................... 14 36-11 ENGINE BLEED AIR SUPPLY SYSTEM....................................... 16 HP BLEED AIR VALVE DESCRIPTION................................................... 22 HP BLEED AIR THERMAL RESISTANCE............................................... 23 LP BLEED AIR CHECK VALVE DESCRIPTION..................................... 24 BLEED AIR SHUT OFF VALVE DESCRIPTION...................................... 25 BLEED AIR CHECK VALVE DESCRIPTION........................................... 26 CROSS FEED VALVE DESCRIPTION..................................................... 27 36-13 WING LEADING EDGE VENTILATION SYSTEM.......................... 28 36-20 INDICATING....................................................................................... 30 BLEED AIR OVERTEMPERATURE SWITCHES DESCRIPTION........... 31 BLEED AIR PRESSURE SWITCH DESCRIPTION.................................. 33 36-22 AIR LEAK DETECTION SYSTEM DESCRIPTION........................ 35 AIR LEAK DETECTION SYSTEM OPERATION...................................... 37 CONTROL UNIT DESCRIPTION.............................................................. 38 SENSING ELEMENTS DESCRIPTION.................................................... 39 INDICATORS AND CONTROL PANELS ON ATR 500 SERIES............. 41 AIR BLEED PANEL.................................................................................. 41 INDICATORS AND CONTROL PANELS ON ATR 600 SERIES............. 43 MAINTENANCE PRACTICES.................................................................. 50 AIR LEAK DETECTION SYSTEM OPERATIONAL TEST/CHECK......... 50 AIR LEAK DETECTION SYSTEM CHECK.............................................. 51 ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 3 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC TABLE OF FIGURES LP OR HP STAGES........................................................................................ 5 BLEED AIR SYSTEM SYMBOLS ON ATR 600 SERIES (2)....................... 45 GENERAL DESCRIPTION............................................................................. 6 CONTROL PANELS LOCATION ON ATR 600 SERIES............................. 46 COCKPIT PANELS ON ATR 500 SERIES..................................................... 7 "X VALVE” INDICATION ON ATR 600 SERIES......................................... 47 FEATURES..................................................................................................... 8 RH MAINTENANCE PANEL ON ATR 600 SERIES.................................... 48 HOTEL MODE................................................................................................ 9 MCDU READOUT ON ATR 600 SERIES..................................................... 49 CROSS FEED............................................................................................... 10 AIR LEAK DETECTION SYSTEM OPERATIONAL TEST/CHECK............ 50 MAGNETIC INDICATORS BITE LOADED ON ATR 500 SERIES.............. 11 AIR LEAK DETECTION SYSTEM CHECK.................................................. 51 ENGINE 2 OIL COOLING IN HOTEL MODE............................................... 12 SAFETY AND PRECAUTIONS.................................................................... 13 PNEUMATIC SYSTEM - SCHEMATIC......................................................... 15 ENGINE BLEED AIR SUPPLY SYSTEM DESCRIPTION........................... 16 ENGINE BLEED AIR SUPPLY SYSTEM LOCATION ON A/C.................... 17 ENGINE BLEED AIR SUPPLY SYSTEM DESCRIPTION........................... 18 AIR BLEED................................................................................................... 19 ENGINE BLEED AIR SUPPLY SYSTEM DESCRIPTION........................... 21 HP BLEED AIR VALVE DESCRIPTION...................................................... 22 HP BLEED AIR THERMAL RESISTANCE DESCRIPTION......................... 23 LP BLEED AIR CHECK VALVE DESCRIPTION......................................... 24 BLEED AIR SHUT OFF VALVE DESCRIPTION......................................... 25 BLEED AIR CHECK VALVE DESCRIPTION............................................... 26 CROSS FEED VALVE DESCRIPTION........................................................ 27 DEACTIVATION OF THE CROSS FEED VALVE........................................ 29 MP TASK ATR-A-36-11-20-00001-560A-A.................................................. 29 CROSS FEED VALVE DEACTIVATION...................................................... 29 BLEED AIR CONTROL PANEL................................................................... 30 BLEED AIR OVERTEMPERATURE SWITCHES LOCATION ON A/C....... 31 BLEED AIR OVERTEMPERATURE SWITCHES DESCRIPTION............... 32 BLEED AIR PRESSURE SWITCH LOCATION ON A/C.............................. 33 BLEED AIR PRESSURE SWITCH DESCRIPTION..................................... 34 AIR LEAK DETECTION SYSTEM LOCATION ON A/C.............................. 35 AIR LEAK DETECTION SYSTEM DESCRIPTION...................................... 36 AIR LEAK DETECTION SYSTEM OPERATION......................................... 37 CONTROL UNIT DESCRIPTION.................................................................. 38 SENSING ELEMENTS DESCRIPTION........................................................ 39 AIR BLEED PANEL...................................................................................... 42 CONTROLS AND INDICATORS ON ATR 600 SERIES.............................. 43 BLEED AIR SYSTEM SYMBOLS ON ATR 600 SERIES (1)....................... 44 ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 4 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC 36-00 PNEUMATIC GENERAL DESCRIPTION The pneumatic system supplies aircraft systems which use pressurized air. These systems are: ‒ Air conditioning, ‒ Ventilation, ‒ Pressurization, ‒ De-icing. Compressed air is bled from the engine compressors at the LP or HP stages. ‒ Look at the following picture to find the LP and HP ports on the engine. Bleed air protection systems are: ‒ OVERHEAT, two thermal sensors are fitted on pneumatic ducts, downstream of the bleed air shut-off valve. ‒ OVERPRESSURE, a pressure sensor is installed upstream the bleed air shut-off valve. ‒ AIR LEAK, sensing elements are fitted beside the bleed air ducts. The LP and HP ducts join together to form a single duct. Temperature switches monitor the bleed air, which flows through the bleed air shut-off valve. Check valves are fitted on the LP ports. They prevent reverse flow towards the LP compressor, when HP pressure is used (HP bleed valve opens at low power engine range). Both bleed air shut-off valve and HP valve are controlled by engine bleed push button on overhead panel. A check valve is fitted on the LH duct. It prevents reverse flow to the left engine bleed, during Hotel Mode. A crossfeed valve permits the interconnection of subsystems bleed ducts to supply both air conditioning packs. Opens only on ground. De-ice system is supplied with bleed air from the HP port. LP OR HP STAGES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 5 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC GENERAL DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 6 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC COCKPIT PANELS ON ATR 500 SERIES COCKPIT PANELS ON ATR 500 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 7 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC INTERFACES FEATURES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 8 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC FEATURES This mode, available on the RH engine, is used on ground only, to provide Hotel Mode works with the LP and HP stages running and the propeller brake aircraft electrical supply and air conditioning. locked. HOTEL MODE ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 9 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC The crossfeed valve installed on the crossfeed duct is designed to connect LH and RH air bleed ducts. ‒ On ground, it is open only when one engine is running or when propeller brake is engaged. ‒ In flight, the crossfeed valve is closed. CROSS FEED ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 10 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC When an HP valve 1(2) fails, magnetic indicator turns yellow. MAGNETIC INDICATORS BITE LOADED ON ATR 500 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 11 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC When engine 2 operates in Hotel Mode, two air ventures enable activation of the air flow through the oil cooler. ENGINE 2 OIL COOLING IN HOTEL MODE ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 12 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC PNEUMATIC SAFETY PRECAUTIONS DURING MAINTENANCE SAFETY AND PRECAUTIONS ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 13 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC 36-10 DISTRIBUTION The pneumatic distribution system directs and controls the distribution of pressurized air required to operate: ‒ Air conditioning system ‒ Ice protection system. The pneumatic distribution also provides pressurized air for cabin pressure control system jet pump. The distribution system includes ducting, various valves, sensing elements and pressure regulators to maintain controlled pressure and temperature and to limit the airflow. ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 14 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC PNEUMATIC SYSTEM - SCHEMATIC ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 15 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC 36-11 ENGINE BLEED AIR SUPPLY SYSTEM The pneumatic system consists of two separate bleed duct subsystems, left Each bleed duct subsystem is fed by the corresponding LP and HP engine and right. compressors. ENGINE BLEED AIR SUPPLY SYSTEM DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 16 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC The ducts from the LP and HP ports join inside the engine nacelle to form a single duct. Several valves and pneumatic components are fitted on this duct. The duct passes from the engine nacelle through the centre wing leading edge, the interspace between the fuselage external skin and internal lining to the front undercarriage area. ENGINE BLEED AIR SUPPLY SYSTEM LOCATION ON A/C ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 17 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC Air is usually bled from the Low Pressure (LP) compressor stage. When pressure from the LP stage is < 25 psi, the bleed air source is automatically switched to the High Pressure (HP) compressor stage. HP Two flow limiting venturis are installed inside the LP and HP bleed ducts bleed valve opens at low power engine ranges and regulates air pressure at immediately after the compressor outlets. They provide protection against 25 psi in flight and 38 psi on ground. excess bleed overflow, into the engine nacelle, in case of downstream duct failure. A Bleed Air Shut-Off valve is fitted immediately downstream the engine fire- wall in the fairing between the engine nacelle and the wing. It controls bleed A LP Check valve, installed in the LP bleed duct at the engine bleed port, airflow for the air conditioning. prevents reverse flow towards the LP compressor, when the HP bleed valve is opened. Overpressure switch is installed upstream the bleed air shut-off valve, to avoid overpressure on the ducts. ENGINE BLEED AIR SUPPLY SYSTEM DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 18 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC Two thermal switches are installed downstream the bleed air shut-off valve, The Engine Bleed push button electrically supplies the HP Bleed Valve and to avoid overtemperature on the ducts. In case of an air overheat, an OVHT Bleed Air shut-off valve, which are pneumatically actuated. They associated light illuminates on the Air Bleed panel. automatically close when OVHT, Leak, overpressure, Fire handle pulled or prop brake on (left valve only) and during engine start. A fault light indicates Bleed Air check valve avoids airflow towards left engine compressor, in Hotel that Bleed Air shut-off valve position disagrees with the push button selection, mode. This valve is installed only on LH side. or in case of OVHT, Leak, or valve failure. A Crossfeed valve is installed in the pressurized underfloor area. The X valve A leak detection system is installed downstream the bleed air shut-off valve. open light, on the air bleed panel, illuminates when the crossfeed valve is The system monitors duct air leaks up to the air conditioning pack valve. In open (only on ground). case of air leak detection, an associated Leak light illuminates on the Air Bleed Panel. AIR BLEED ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 19 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC A/C on ground: Overpressure detected. ‒ Both engines are shut down, ‒ When bleed air pressure > 80 psi is detected in the RH bleed air duct ‒ Engine 1 (2) bleed push button are press in, by the RH overpressure switch: ‒ Prop brake is on. ‒ RH bleed shut-off valve close, ‒ RH engine 2 bleed push button fault amber light illuminates. Engine 1 (2) bleed push button fault lights are illuminated. Valve will re-open when pressure will become normal A/C on ground. Engine 2 start: ‒ RH HP valve opens, Note: Same on LH side. ‒ NH 45% + 30s: RH bleed shut-off valve opens, ‒ Engine 2 bleed push button fault light extinguishes, Air overheat detected. ‒ X valve open light illuminates. If a temperature in the RH bleed air duct exceeds 274 °C, the RH Pneumatic system is regulated at 38 psi. overtemperature switches cause: ‒ RH bleed shut-off valve to close, A/C on ground. ‒ RH HP bleed valve to close, ‒ RH OVHT light is illuminated, Engine 1 start: ‒ RH engine 2 bleed push button fault amber light illuminates. ‒ LH HP valve opens, ‒ LH bleed shut-off valve stays closed. Note: Same on LH side. A/C on ground. Engine fire handle pulled. ‒ PROP BRAKE is now set to off, ‒ X valve open light extinguishes, When engine 2 fire handle is pulled, it causes: ‒ LH bleed shut-off valve opens. ‒ RH bleed shut-off valve to close, ‒ RH HP bleed valve to close, A/C in flight. ‒ RH engine 2 bleed push button fault amber light illuminates. ‒ When PL angle is set > 37 °: ‒ HP valves close, Note: Same on LH side. ‒ Pneumatic system is supplied with LP port. ‒ When PL angle is set < 37 ° and pressure is < 25 psi: ‒ HP valves open, ‒ Pneumatic system is regulated at 25 psi. ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 20 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC ENGINE BLEED AIR SUPPLY SYSTEM DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 21 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC HP BLEED AIR VALVE DESCRIPTION The valve is fitted on the HP manifold located in the engine nacelle. HP valve low pressure reference is: 25 psi. HP valve is normally closed. It is a shut-off valve with a dual differential With both solenoids energized, the valve operates at high reference pressure pressure regulator which regulates HP bleed air pressure supply in low power only on ground. conditions and during ground operation. HP valve high pressure reference is: 38 psi. With both solenoids de-energized the valve is closed. Valve position is monitored by micro-switches. HP valve is energized with corresponding PL angle between 13° and 37°. With only the shut-off solenoid energized, the valve is ready to open and uses low reference pressure as required to maintain bleed air duct pressure. HP BLEED AIR VALVE DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 22 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC HP BLEED AIR THERMAL RESISTANCE This platinum resistance sensor inside a hermetic stainless steel case on the When this thermal sensor detects a temperature > 270° C on HP port, the HP engine HP compressor stage. bleed valve is closed and the MFC bite loaded magnetic indicator (located on maintenance panel), turns yellow. The resistance of the sensor changes with temperature. No caution light on the engine Air Bleed Panel (22 VU). Note: This function is only activated on ground. HP BLEED AIR THERMAL RESISTANCE DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 23 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC LP BLEED AIR CHECK VALVE DESCRIPTION The valve is fitted in the LP manifold located in the engine nacelle. It has two semi circular butterfly flaps. The flaps are held closed by means of a spring. An arrow on the body indicates airflow direction. The valve prevents reverse airflow into the engine LP compressor when the HP bleed is operating. LP BLEED AIR CHECK VALVE DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 24 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR SHUT OFF VALVE DESCRIPTION It is a spring-loaded, normally closed shut-off valve, which is pneumatically When the solenoid is de-energized the valve closes. actuated and electrically controlled. Note: This valve is closed during engine start until NH 45% + 30s. With the solenoid energized the valve is ready to open. When air is available, the valve opens. BLEED AIR SHUT OFF VALVE DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 25 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR CHECK VALVE DESCRIPTION The flaps are held closed by means of a spring. An arrow on the body indicates air flow direction. The valve prevents reverse airflow to the left engine compressors when the right engine is operating in Hotel Mode. BLEED AIR CHECK VALVE DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 26 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC CROSS FEED VALVE DESCRIPTION It is an electrically controlled, pneumatically actuated shut-off valve. It interconnects the right and the left ducting to allow bleed air to flow from the system which is operating to the other side. When the solenoid is energized the valve is ready to open. When bleed air is available, the valve opens. When solenoid is de-energized the valve closes. CROSS FEED VALVE DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 27 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC 36-13 WING LEADING EDGE VENTILATION SYSTEM The wing leading edge ventilation system maintains a low temperature level In flight only, ventilation is obtained by means of a ram air intake scoop (also inside the portion of the wing leading edges between fuselage and engine called NACA air inlet), located in the top of the engine nacelle. nacelles. A distribution duct is also installed in the leading edge internal area. The system allows eventual fuel vapors to escape, preventing possible fire due to a hot air bleed duct leakage. No monitoring or control is provided. WING LEADING EDGE VENTILATION SYSTEM DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 28 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC DEACTIVATION OF THE CROSS FEED VALVE Fault symptom: On panel 22 VU on AIR BLEED/ENG1(2) BLEED P/BSW, MP TASK ATR-A-36-11-20-00001-560A-A FAULT legend is illuminated and, on ENG1(2) BLEED/OVHT/LEAK caution light OVHT legend is illuminated (even after resetting the system) Note: The valve must be removed without disturbing or re-adjusting the support rods. Fault Isolation: TASK ATR-A-36-11-XX-03004-421A-A BLEED OVHT 1. Disconnect electrical connector (6). 2. Remove clamps (4) and (5). A. Go to the Fault Confirmation: Ref. AFI ATR-A-36-11-XX-03ZZZ-429Z-A. 3. Note direction of airflow arrow on valve body and remove valve (1). 4. Blank off electrical connector (6), stow it and secure with tape. Note: For this procedure, these documents are useful for reference: ASD. 5. Install blanking cap (3) for 2.5'' duct on duct coming from right engine (2). 6. Install the PLACARD - INOP on the pushbutton related to the deactivated Go to Step B. valve. B. On the fault side, replace the switches: OVER TEMPERATURE SWITCH- ENG 1/2 BLEED (11HA/12HA) and OVER TEMPERATURE SWITCH-ENG 1/2 BLEED (13HA/14HA) Ref. MP ATR-A-36-11-60-03ZZZ-520Z-A/ MP ATR- A-36-11-60-03ZZZ-720Z-A. Does the fault continue? YES (Go to Step C.) / NO (Go to Step G.) C. On the fault side, examine the wiring: Ref. ASD ATR-A-36-11-XX-01ZZZ- 054Z-A. From connector 21HA/11HA/13HA to 11HA/13HA/15HA and from connector 22HA/12HA/14HA to 12HA/14HA/16HA. Is the wiring OK? YES (Go to Step D.) / NO (Go to Step E.) D. On the fault side, replace the sensor:-SENSOR-HIGH PRESSURE AIR BLEED TEMPERATURE, ENG 1/2 (19HA1/19HA2).Ref. MP ATR-A-36-11- 60-05ZZZ-520Z-A and Ref. MP ATR-A-36-11-60-05ZZZ-720Z-A. Does the fault continue? YES (Go to Step F.) / NO (Go to Step G.) E. Refer to the related AWD to correct the wiring defects. Go to Step G. F. Ref. DMC PW127-0A-72-00-00-00A-410A-D (00198) / Ref. EMM-PWC 720000. Go to Step G. G. Go to the Close-up. Close-Up A. Put the aircraft back to its initial configuration. CROSS FEED VALVE DEACTIVATION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 29 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC 36-20 INDICATING The pneumatic system controls and indicating consist of pushbutton switches, caution lights and test switch, that enable the crew to operate the system. Information is provided on its functioning, particularly overheating or duct leaks, that can cause eventual damage to aircraft structure, interior panels and components in the vicinity of hot air ducts. BLEED AIR CONTROL PANEL ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 30 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR OVERTEMPERATURE SWITCHES DESCRIPTION BLEED AIR OVERTEMPERATURE SWITCHES LOCATION ON A/C ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 31 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC They are hermetically sealed, stainless steel probes. They monitor the air bleed. In case of overtemperature, the bleed air shut-off valve and the HP bleed valves are closed, OVHT light illuminates on the air bleed control panel. The operating range of the bleed air overtemperature switches is 274 ± 6,7 °C (525 ± 12 F), and the reset temperature is 250 °C (482 F). The hystersis value is 5,55 °C (10 F) below the switching temperature. BLEED AIR OVERTEMPERATURE SWITCHES DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 32 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR PRESSURE SWITCH DESCRIPTION The pressure switch is fitted on the bleed air duct, upstream the bleed air When the bleed air pressure detected by the overpressure switch decreases shut-off valve. to 70 psi, bleed air shut-off valve can re-open. When air bleed pressure > 80 psi, overpressure switch sends a signal to the MFC which closes the bleed air shut-off valves. Fault light illuminates on the corresponding air bleed push button. BLEED AIR PRESSURE SWITCH LOCATION ON A/C ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 33 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR PRESSURE SWITCH DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 34 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC 36-22 AIR LEAK DETECTION SYSTEM DESCRIPTION The air leak detection system is a continuous monitoring system. The system is installed in order to detect duct leakages by thermal wire sensing element. Air leak detection system consists of two subsystems, one for each bleed system. This system is installed in the following areas: ‒ Wing leading edge and wing to fuselage fairing, ‒ Upper and lower fuselage floor, ‒ Air conditioning pack area. AIR LEAK DETECTION SYSTEM LOCATION ON A/C ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 35 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC The air leak detection system consists of two single loops, one for each engine, a control unit and an indicating system. In order to ensure rapid leak sensing, a Kevlar envelope is installed around the major part of the high temperature ducts to collect and direct leaking air to the sensing elements. Each loop consists of six sensing elements located along the engine bleed air ducts. The air leak detection system protects LH and RH bleed air shut-off valves and the crossfeed valve ducts. AIR LEAK DETECTION SYSTEM DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 36 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC AIR LEAK DETECTION SYSTEM OPERATION When an element of the leak detection wire heats to the alarm temperature of Note: If an air leak occurs on RH bleed air duct, RH HP and shut-off valves 153 ± 8 °C, the air leak control unit sends a signal. close with the same sequence. This electrical signal illuminates the corresponding LEAK legend and, after one second delay, the bleed air shut-off valve and HP valve close. In case of a left engine duct air leak: ‒ Left bleed shut-off valve closes, ‒ Left hp bleed valve closes, ‒ Crossfeed valve closes (if open) and is inhibited to open. AIR LEAK DETECTION SYSTEM OPERATION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 37 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC CONTROL UNIT DESCRIPTION The control unit is installed on shelf 92VU in the electronic rack. It is an electronic device with two monitoring circuits. The level circuit initiates an alarm when the impedance of the continuous element reaches a predetermined low level. CONTROL UNIT DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 38 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC SENSING ELEMENTS DESCRIPTION Sensing elements are fitted closed to the pneumatic ducts. When an air leak The air leak wiring is composed of: occurs, the air is drawn to holes, located in front of the leak detection wire. ‒ Pure nickel, ‒ Porous aluminium oxide, The elements consist of a solid nickel conductor embedded in an insulating ‒ Inconel tubing. material and encased in an inconel tube hermetically sealed at both ends. They are located along all the bleed air ducting. When the element heats up to the alarm temperature of 153 ± 8 °C,, the control unit emits a signal to illuminate the corresponding LEAK legend and, The voids and clearances between the tubing, porous ceramic insulators, and after a one second delay, the bleed air shut-off and HP valves close (X feed centre conductors are saturated with an eutectic salt mix. valve also if open). When the element is exposed to hot gasses or any overheat condition, the impedance between the centre conductor and outer casing drops sharply. SENSING ELEMENTS DESCRIPTION ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 39 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC Fault symptom: On panel 22VU on AIR BLEED/ENG1(2) BLEED/OVHT/LEAK, caution light LEAK legend is illuminated Fault Isolation: TASK ATR-A-36-22-XX-02001-421A-A G. If necessary, remove and install the sensing elements as per: Bleed Leak - Ref. MP ATR-A-36-22-20-00ZZZ-520Z-A and Ref. MP ATR-A-36-22-20- 00ZZZ-720Z-A and/or A. Go to the Fault Confirmation: Ref. AFI ATR-A-36-22-XX-02ZZZ-429Z-A. - Ref. MP ATR-A-36-22-50-00ZZZ-520Z-A and Ref. MP ATR-A-36-22-50- 00ZZZ-720Z-A and/or - Ref. MP ATR-A-36-22-70-00ZZZ-520Z-A and Ref. MP ATR-A-36-22-70- Note: For this procedure, these documents are useful for reference: ASD, 02ZZZ-720Z-A. AWD Go to Step J. Go to Step B. H. On the fault side, examine the connections between the sensing elements and the wiring. B. Examine the wiring as per Ref. ASD ATR-A-36-22-XX-01ZZZ-054Z-A: From connector 5HF to7HF If there are no other defects, replace the sensing elements and the wiring. Is the wiring OK? YES (Go to Step C.) / NO (Go to Step F.) Go to Step J. C. On the fault side, do a visual inspection of the sensing elements as per Ref. MP ATR-A-36-22-XX-00ZZZ-364Z-A. Are there defects? YES (Go to I. Replace P/BSW-AIR BL LEAK / PTT (5HF). Go to Step J. Step G.) / NO (Go to Step D.) J. Go to the Close-up. D. On the fault side, measure continuity as per: Ref. AWD ATR-A-36-22-XX- 01ZZZ-051Z-A and Ref. AWD ATR-A-36-22-XX-02ZZZ-051Z-A Close-Up From connector 922VCA pin 49 to 922VCA pin 50 and from 923VCA pin 49 A. Put the aircraft back to its initial configuration. to 923VCA pin 50. Is there continuity? YES (Go to Step E.) / NO (Go to Step H.) E. Replace the CONTROLLER-AIR LEAK DETECTION (7HF) as per Ref. MP ATR-A-36-22-10-00ZZZ-520Z-A and Ref. MP ATR-A-36-22-10-00ZZZ-720Z- A. Does the fault continue? YES (Go to Step I.) / NO (Go to Step J.) F. Correct wiring defects: Ref. ASD ATR-A-36-22-XX-01ZZZ-054Z-A. Go to Step J. ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 40 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC INDICATORS AND CONTROL PANELS ON ATR 500 SERIES AIR BLEED PANEL Look at the Air Bleed Panel. X VALVE OPEN light. ‒ Amber light illuminates when the crossfeed valve is open. ‒ Open on ground only. ‒ Inhibited in flight. ‒ Auto open when only one engine is running (Hotel Mode or Taxiing). OVHT light. ‒ Amber light illuminates when bleed duct temperature exceeds 274 °C (525 F). ‒ Auto closes bleed valves (shut-off and HP). ‒ Associated engine bleed push button may be reseted after cooling. LEAK light. ‒ Amber light illuminates when loop temperature exceeds 153 °C. ‒ Auto closure of shut-off and HP bleed valves (one second delay) and crossfeed valve if used on ground. Engine 2 (1) Bleed Push button. Controls both bleed air shut-off and HP bleed valves. Inhibited during engine start. ‒ FAULT: amber light illuminates in case of bleed valve position disagreement with the relevant push button (Lack of bleed air or electrical supply, OVHT, Leak and Fire handle pulled). ‒ OFF: white light illuminates with push button released. HP and bleed valves are closed. ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 41 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC AIR BLEED PANEL ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 42 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC INDICATORS AND CONTROL PANELS ON ATR 600 SERIES Pneumatic System indications are given on AIR BLEED Panel (located on the "FAULT" amber light illuminates in case of Bleed Air Shut-Off Valve position Overhead Panel) and on SD Cabin page of the Multi Function displays disagreement with the relevant pushbutton. State 2 is displayed on MFD. (located on the Instrument Panel). These alarms illuminate in case of lack of bleed air or electrical supply. ENG 1 (2) BLEED air pushbutton controls both Bleed Air Shut-Off and HP ‒ Overpressure: Pressure above 80 PSI, Bleed Valves. Inhibited during engine start. "ON" (pushbutton depressed ‒ Overheat: Temperature above 274°C, without lighting) normal operation, the Bleed Air Shut-Off Valve is open. ‒ Leak: Temperature above 153°C and Fire Handle pulled. State 1 is displayed on MFD. "OFF" white light illuminates with the pushbutton released. HP Bleed Valve and Bleed Air Shut-Off Valve are closed. State 3 is displayed on MFD. Note: The HP Bleed Valve opens at low Engine power. CONTROLS AND INDICATORS ON ATR 600 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 43 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR SYSTEM SYMBOLS ON ATR 600 SERIES (1) ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 44 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC BLEED AIR SYSTEM SYMBOLS ON ATR 600 SERIES (2) ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 45 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC "OVHT" amber light illuminates when bleed duct temperature exceeds 274°C "LEAK" amber light illuminates when the Loop temperature exceeds 153°C. (525 F). State 1 is displayed on MFD. State 2 is displayed on MFD. Auto closure of Bleed Valves (Shut-Off and HP). Auto closure of Bleed Valves (Shut-Off and HP) after one second delay and Crossfeed Valve if used on ground. Associated Engine bleed pushbutton may be reseted after cooling. CONTROL PANELS LOCATION ON ATR 600 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 46 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC "X VALVE OPEN" amber light is extinguished when the Crossfeed Valve is "X VALVE OPEN" amber light is illuminated when the Crossfeed Valve is closed with both Engines running or both Engines shut down. Nothing is stuck open with both Engines running. State 2 is displayed on MFD. displayed on MFD. "X VALVE OPEN" amber light is illuminated when the Crossfeed Valve is "X VALVE OPEN" amber light is illuminated when the Crossfeed Valve is stuck open with both Engines shut down. State 3 is displayed on MFD. open. State 1 is displayed on MFD. "X VALVE OPEN" amber light is extinguished when the Crossfeed Valve is The valve is: stuck closed with both Engines running. State 4 is displayed on MFD. ‒ Open on ground only. ‒ Inhibited in flight. ‒ Auto open when only one Engine is running (Hotel Mode or Taxiing). ‒ Open with one Engine Bleed Air pushbutton released and both Engines running. "X VALVE” INDICATION ON ATR 600 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 47 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC Pneumatic System recorded failure indication and test are given on RH AIR BL LEAK PTT switch permits to check the continuity of the Loops, the Maintenance Panel, for maintenance purpose only. MFC bite loaded indicator controller and the associated warnings. indicates that HP Bleed Valve failures are recorded in the MFC memory. RH MAINTENANCE PANEL ON ATR 600 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 48 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC Pneumatic System failure codes and Valves positions can be read through HP Bleed Valve position can be read in Alpha Call Up page of the MCDU. the MCDU. HP Bleed Valve failure codes can be read in Miscellaneous 1 page of the MCDU. MCDU READOUT ON ATR 600 SERIES ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 49 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC MAINTENANCE PRACTICES AIR LEAK DETECTION SYSTEM OPERATIONAL TEST/CHECK Air Leak push button test: Depressing the air leak momentary switch, located on the maintenance panel causes the leak lights to illuminate. Both engine loops are tested simultaneously by pressing the Air Bleed Leak PTT push button switch. This test checks the continuity of the loops, the controller and the associated warnings. The push button is located on maintenance panel 702VU: ‒ If the Leak indicators illuminate, the system is functional. If the test is performed with engines running, the results are the same but the ‒ If any indicator remains off when the PTT button is pressed, a fault engine 1 (2) bleed do not close. exists in the relevant sensing element. AIR LEAK DETECTION SYSTEM OPERATIONAL TEST/CHECK ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 50 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC AIR LEAK DETECTION SYSTEM CHECK Air Bleed Leak PTT push button is pressed on maintenance panel. Only one Leak amber light illuminates. The Leak bulbs are checked with the annunciator light test and both Leak lights illuminate. After trouble shooting operation one loop open circuit has been detected. Air leak detection system check has to be performed, with the following sequence: 1 - LH or RH wing leading edges, 2 - LH or RH wing to fuselage fairings, 3 - LH or RH fuselage sidewalls, 4 - fuselage underfloor, 5 - LH or RH conditioning pack area. AIR LEAK DETECTION SYSTEM CHECK ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 51 ATR 42-500/72-212A (PWC PW120) ATA 36 B1.1 AND B2 (SUB-)CATEGORIES PNEUMATIC THIS PAGE IS INTENTIONALLY LEFT BLANK ISSUE 1, 5 MAY 2023 FOR TRAINING PURPOSES ONLY Page: 52