ATA 30 Ice & Rain Protection PDF January 2023

BOMBARDIER DHC 8-400 (PWC PW150) ATA 30 - ICE & RAIN PROTECTION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY B1/B2 MAINTENANCE TRAINING MANUAL Issue 6 - January 2023 Page 1 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PURPOSE The Ice and Rain Protection System removes ic...

BOMBARDIER DHC 8-400 (PWC PW150) ATA 30 - ICE & RAIN PROTECTION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY B1/B2 MAINTENANCE TRAINING MANUAL Issue 6 - January 2023 Page 1 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PURPOSE The Ice and Rain Protection System removes ice from the: • • • • Leading edges of wings Horizontal stabilizers Vertical stabilizers Engine nacelle inlets The leading edges of the propeller blades are electrically de-iced. The windshields and the pilot side window are protected from: • • • Ice Rain Cold shock TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 2 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION INTRODUCTION The Ice and Rain Protection System (IRPS) does: • • • • Ice detection De-icing Anti-icing Rain removal The Anti-icing Systems are thermal, using electrical heating elements to prevent ice formation. Conventional electrically operated windshield wipers provide rain removal from the windshields. The Ice Detection System (IDS) detects ice build-up. The IRPS has these sub-systems: • • • • • • Airframe De-icing System Air Intake De-icing System Pitot and Static Anti-Icing System Windshield and Windows Ice and Rain Protection System Propellers Ice Protection System Ice Detection System TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 3 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION When heat is selected ON, all six blades on one side of the aircraft are heated at one time, then the propeller on the other side is heated. GENERAL DESCRIPTION The airframe de-icing system is divided into two identical subsystems, one subsystem per engine. The Ice Detection System (IDS) gives early detection and indication of aircraft icing conditions and is activated when 115V AC electrical power is available. When ice accumulation is sensed the words ICE DETECTED appear on the Engine Display (ED). Each subsystem uses bleed air from its related engine to inflate boots on: • • • • The leading edges of the wings Horizontal stabilizer Vertical stabilizer Nacelle air intakes The inflation of the boots removes the accumulated ice from these surfaces. Both subsystems are connected to each other through an Isolation Shut-Off Valve (ISOV). The rear parts of the subsystems in the aft fuselage are also connected by a restrictor. The air intake de-icing system has: • • Electrical heating elements on the inner surface of the intake adapter Pneumatic de-icing boots that form the air intake lip Three pitot-static probes have electrical heating elements to prevent icing. Icing can cause incorrect pitot or static measurements. The windshields and the pilot side window have electronically controlled heater elements laminated into the panels to keep them at a predetermined temperature. This prevents icing and misting. Windshield wipers remove rain from the windshields. The Propeller Anti-Icing System has electrical heating elements in the leading edge of each propeller blade to remove ice accumulations. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 4 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ICE AND RAIN PROTECTION SYSTEMS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 5 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS PURPOSE The airframe de-icing system uses engine bleed air pressure reduced through a regulator to operate a series of inflatable/deflatable boots. The inflating and deflating action of the boots removes the accumulation of ice on the leading edges of the aircraft. GENERAL DESCRIPTION The airframe de-icing system has two identical subsystems, one subsystem per engine. Each subsystem uses bleed air from its related engine to inflate boots on the: • • • • Leading edges of the wings Horizontal stabilizer Vertical stabilizer Nacelle air intakes The inflation and deflation of the boots removes the accumulated ice from these surfaces. Both subsystems are connected to each other through an Isolation Shut-Off Valve (ISOV). The rear parts of the subsystems (in the aft fuselage) are also connected by a restrictor. Four automatic drain valves in the system prevent accumulation of water which could freeze and cause the system to malfunction. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 6 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - DEICE DISTRIBUTION BLOCK DIAGRAM TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 7 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION When the AIRFRAME MODE SELECT switch is in the MANUAL position, individual boots can be inflated using the second switch labelled AIRFRAME MANUAL SELECT. This switch has 8 positions, 6 positions for the 6 phases of airframe de-icing cycle and two for the OFF position. Inflation of a series of boots is possible by rotating the AIRFRAME MANUAL SELECT switch to the desired boot settings. AIRFRAME DE-ICING SYSTEMS GENERAL DESCRIPTION Three switches control the de-icing system. These switches are located on the ICE PROTECTION control panel and are labelled: • • • In the NORM position, the Isolation Shut-off Valve (ISOV) is open connecting the left and right de-icing systems. In the ISO position, the ISOV is closed and the left and right de-icing systems are independent from each other. AIRFRAME MODE SELECT AIRFRAME MANUAL SELECT BOOT AIR The AIRFRAME MODE SELECT switch selects the operating mode of the de-icing system. Four modes are available: • • • • In the OFF mode, automatic de-icing is inhibited and only manual de-icing is permitted. The TMU controls the de-icing system heaters based on SAT information. The BOOT AIR switch has two positions: NORM and ISO. FAST SLOW OFF MANUAL Monitoring of the boot operation is done by observing eight boot inflation advisory lights for the wings, and four boot inflation advisory lights for the tail. All twelve advisory lights are located on the ICE PROTECTION control panel. A boot inflation advisory light comes on when there is a pressure increase in that boot. When this switch is selected to slow or fast the Timer and Monitor Unit (TMU) controls the automatic operation of the de-icing system by regulating the inflation sequence of the pneumatic boots. Individual boot selection is possible when the AIRFRAME MODE SELECT switch is in the MANUAL or OFF position. In the automatic modes (FAST and SLOW), the airframe is de-iced according to a predefined cycle controlled by the Timer Monitor Unit (TMU). The cycle is divided into 6 sequences of inflation and a dwell period. Each sequence consists of inflation of an individual boot for 6 seconds followed by suck down of that boot (dwell period) until the next cycle. When in SLOW mode, the deice cycle lasts 3 minutes. When in FAST mode, the deice cycle lasts 1 minute. The de-icing system heaters are controlled by the TMU using the static air temperature (SAT) data. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 8 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ICE PROTECTION SYSTEM PANEL TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 9 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION delivers air to the six dual distributor valves (DDV), which when signalled by the Timer Monitor Unit (TMU) causes the boots to inflate briefly and shed ice accumulations. The sequence consists of 6 boot inflation cycles of 6 seconds duration. The air is supplied from the engines through one Pressure Regulating Valve (PRV) with a Check Valve (CV) in each nacelle. AIRFRAME DE-ICING SYSTEMS GENERAL DESCRIPTION To prevent water accumulation inside the system or inside the boots, drain valves are located at the low point in the lines. The drain valves are automatic and close upon pressurization of the system at engine start-up when pressure is 5 psig (34.5 kPag). They open when the pressure is below 3 psig (20.6 kPag), so that accumulated water can be released in to the wing leading edge or the rear fuselage at engine shutdown when the system is depressurized. DETAILED DESCRIPTION The manifold along the wing front spar has a normally open Isolation Shut-Off Valve (ISOV). In each wing the manifold supplies air to the boots through two Dual Distributing Valves (DDV). The two branches deliver air to the rear fuselage through heated check valves and two more DDV. A heated restrictor is located between each system and downstream from the heated check valves. The check valves and restrictor prevent any loss of pneumatic supply to the tail boots if one of the supply branches looses air. The left manifold has a 0.25 in branch pipe that supplies air to the Door Seal System. The Aircraft Pneumatic De-icing System includes these components: • • • • • • • • • • • • • Timer and Monitor Unit Pressure Regulating and Relief Valves Isolation Shut-off Valve Dual Distributing Valves Check Valves (non-heated) Restrictor Low Pressure Warning Switches Automatic Drain Valves Pressure Transducers Heated Check Valves Airframe Auto Selector Airframe Manual Selector Boot Air Switch The Pneumatic De-icing System has two 0.75 in diameter manifolds. Each manifold has a pressure transducer connected to a dual indicator in the flight compartment. Each system is regulated to 18 psig +1.5/-1 psig (124 kPag +10.34/-6.89 kPag) and TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 10 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - DEICER BOOTS AND CONTROLS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 11 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS DETAILED DESCRIPTION Monitoring of the boot operation or DDV output status is done by the boot inflation advisory lights on the ICE PROTECTION control panel, or by looking at the boots. The four tail advisory lights correspond to the four horizontal stabilizer boots. The four wing advisory lights correspond to the four groups of boots listed below: • • • • Extension and Outboard boots Outboard centre and Inboard centre boots Inboard boots Centre Wing Boots There are advisory lights that correspond to each engine intake boot. When a de-icing boot inflates, an advisory light comes on to show that the related boot is inflated. The detection of the boot inflation is done by the Low Pressure Switch (LPS) in the DDV. The boot inflation sequence is: • • • • • • • • Outermost pair of outboard wing deice boots Central pair of outboard wing deice boots Left innermost outboard wing deice boot and right inboard wing de-ice boot Right innermost outboard wing deice boot and left inboard wing de-ice boot Left and right innermost horizontal stabilizer deice boot and upper vertical stabilizer de-ice boot No. 1 engine intake deice boot Left and right outermost horizontal stabilizer deice boot and lower vertical stabilizer deice boot No. 2 engine intake deice boot TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 12 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - DEICER BOOTS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 13 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS TIMER AND MONITOR UNIT (TMU) The Timer and Monitor Unit (TMU) is located on the Wardrobe panel. The TMU sequences the Dual Distributing Valves (DDV) operation according to a predefined cycle. It commands the DDV to distribute air supply through one of its outputs. After the inflation cycle time, it commands the DDV to let air flow back and exhaust overboard through the ejector. During this cycle, the timer monitors the operation of the low pressure switches incorporated in each DDV output to confirm the operation of the DDV. The timer controls the de-icing cycles according to the selected operating mode, SLOW or FAST, and also controls the heaters of all heated equipment of the de-icing system. The Static Air Temperature (SAT) information is used to activate the heaters. When SAT falls below a pre-set value, the heaters are activated. When SAT rises above this value, the heaters are deactivated. The TMU also monitors the left and right Engine Intake Adapter Heaters and automatically activates the spare heater when a main heater has failed. The TMU monitors these Air Data Sensor Heaters: • • • Two 115V AC Pitot/Static Probes One 28V DC Pitot/Static Probe (Standby) Two 115V AC Angle of Attack (AOA) Sensors TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 14 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - TIMER AND MONITOR UNIT LOCATION, INPUTS/OUTPUTS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 15 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS PRESSURE REGULATING, RELIEF VALVES AND NON-HEATED CHECK VALVES Each pneumatic deice subsystem is supplied with bleed air from its respective engine. The Pressure Regulating and Relief Valve (PRRV) regulates the pressure according to the bleed flow and provides regulated air supply to the system. Pressure regulation is done using a diaphragm which opens or closes to provide the de-icing system with a constant pressure. In the event of overpressure in the system, the relief port will allow the pressure to decrease. A failure of one PRRV does not prevent the system from operating normally. Failure of both PRRV causes total loss of the pneumatic supply and airframe de-icing. The Non-Heated Check Valves (NHCV) prevents air from the other system from flowing back into the engine system in the event of an engine failure. A faulty NHCV does not prevent the de-icing system from functioning if the two engines are running. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 16 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - PRESSURE REGULATING AND RELIEF VALVE LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 17 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS ISOLATION SHUT-OFF VALVE The Isolation Shut-off Valve (ISOV) is normally closed when not energized. When an engine is started, it is energized open. In the event of a loss of pressure in the system, it may be closed by the flight crew to isolate the two sides. Isolation is electrically commanded using the BOOT AIR ISO switch on the ICE PROTECTION control panel. A failure of the ISOV (fails open) does not prevent the system from operating normally. A duct rupture and an ISOV failure will cause a loss of air supply. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 18 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ISOLATION SHUT OFF VALVE LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 19 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS DUAL DISTRIBUTING VALVES The Dual Distributing Valve (DDV) is either manually commanded open or automatically controlled by the TMU. Each DDV is supplied with air from the system and distributes it to the boots through two separate electrical valves. Each valve is commanded separately, one after the other according to timer sequencing or manual operation. The Low Pressure Switch (LPS) incorporated on each DDV output closes when the pressure increases above 15 psig ± 1 psig (103.4 kPag ± 6.89 kPag) at boot inflation. This switch then sends a signal to the TMU to confirm that the commanded valve has opened normally and that pressure was sufficient to inflate the boots normally. At boot deflation air flows back to the DDV and exhausts from the system through the ejector. The LPS opens when pressure is decreasing through 11psig +2.5/-1 psig (75.8 kPag +17.2/-6.89 kPag), indicating to the TMU that the commanded valve has operated normally. Air from the boots is removed using a venturi effect. This allows the boots to flatten on the leading edge when they are not inflated. The DDV is heated to prevent the electrical valves and the ejector from freezing and to avoid moisture on the connector. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 20 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - DUAL DISTRIBUTING VALVE LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 21 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS RESTRICTOR The restrictor lets air flow from one side of the aft system to the other side. This ensures that the tail is correctly de-iced in the event of a failure upstream of one of the Heated Check Valves (HCV). It also reduces the amount of air loss in case of a failure downstream to allow for partial de-icing of the tail. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 22 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - RESTRICTOR LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 23 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS LOW PRESSURE WARNING SWITCHES The Low Pressure Warning Switch (LPWS) senses low pressure in the system. The LPWS: • • Closes when the pressure inside the system is below 15psig ± 1 psig (103.4 kPag ± 6.89 kPag) Opens when the pressure exceeds 11 psig +2.5/-1 psig (75.8 kPag) When the LPWS is closed, it causes the DEICE PRESS caution light to come on. The LPWS signal is also sent to the TMU for maintenance purposes. Two LPWS are installed in front of the front spar, in the wing to body fairing area. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 24 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - LOW PRESSURE WARNING SWITCH LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 25 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS AUTOMATIC DRAIN VALVES The Automatic Drain Valves (ADV) collect water that has condensed in the system. The valve drains the water when the pressure in the system is below 3 psig (20.7 kPag) at engine shutdown. When pressure in the system is above 3 psig (20.7 kPag), the valve closes to avoid leakage. The ADV is heated to prevent trapped water from freezing and restricting flow. Two are located in the tail and one in each wing upstream of the two DDV. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 26 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - AUTOMATIC DRAIN VALVE LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 27 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS PRESSURE TRANSDUCERS The pressure transducers are sensors that measure system air pressure. They send signals for display on a dual indicator in the flight compartment. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 28 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - PRESSURE TRANSDUCERS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 29 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS HEATED CHECK VALVES The Heated Check Valve (HCV) lets air flow into the aft part of the de-icing system. It prevents air from flowing back to the wing system in the event of a failure upstream of the Check Valve (CV). This allows the tail to be de-iced when a failure occurs in one side of the wing system. In the event that one HCV fails open, the tail system is still operational. If one HCV fails closed it will not prevent the tail system from operating normally. If the second HCV fails closed, air is no longer supplied to the tail section. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 30 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - HEATED CHECK VALVE LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 31 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS CONTROLS AND INDICATIONS AIRFRAME MODE SELECTOR The AIRFRAME MODE SELECT switch selects these operational modes: • • • • MANUAL OFF SLOW FAST The two automatic modes are: • • SLOW FAST When SLOW mode is selected, the deice sequence lasts 180 ± 2.5 seconds. If the FAST mode is selected, the deice sequence lasts 60 ± 2.5 seconds. When the automatic mode is set, manual operation of the de-icing system is inhibited. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 32 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - AIRFRAME MODE SELECTOR LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 33 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIRFRAME DE-ICING SYSTEMS BOOT AIR SWITCH The BOOT AIR ISO switch commands the Isolator Shut-off Valve (ISOV) to close and isolate the left and right sides of the system. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 34 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - BOOT AIR SWITCH LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 35 of 114 BOMBARDIER DHC 8-400 (PWC PW150) • • ICE AND RAIN PROTECTION AIR INTAKE DE-ICING ENGINE INTAKE switch-light has been pushed 115V AC power is available When an ENGINE INTAKE switch-light is pushed, the bypass door of that engine starts to open to evacuate ice pieces shed from nacelle inlet components. The OPN or CLOSED lights show the position of the related bypass doors. PURPOSE When the heaters are powered, the HTR lights in the ENGINE INTAKE switch-lights on the ICE PROTECTION control panel come on. Engine air intake de-icing prevents ice build-up on the engines. GENERAL DESCRIPTION The air intake de-icing system has electrical heating elements on the inner surface of the intake adapter. The engine air intake is integrally anti-iced by reduction gear box scavenge oil heat. The engine air intake adaptor de-icing includes two 1200 W electrical heating elements one main and one spare. Each has an individual ground connection. The left engine air intake adapter heaters are energized by the 115V Aphase C B left variable frequency bus. The 115V Aphase C B right variable frequency bus supplies the right engine air adaptor. Circuit breakers labelled INTK LIP HTR ENG 1 (left) and INTK LIP HTR 2 (right) are on the AC variable CB panel. Each heated adapter is controlled by the ENGINE INTAKE switch-lights on the ICE PROTECTION panel. The heating elements are embedded in epoxy fibreglass and installed on the inner surface of the intake adapter. The heaters are insulated using stay foam polyurethane and are sealed with polysulfide. Power is supplied to the heater through a relay when all of these conditions are correct: • • Temperature measured by a thermostat in the fuselage is below +60°F (+15.6°C) Related engine oil pressure switch is closed TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 36 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ENGINE AIR INTAKE ANTI ICE BLOCK DIAGRAM TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 37 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIR INTAKE DE-ICING AIR INTAKE HEATER THERMOSTATS The thermostat is a thermal/mechanical switch. It is energized closed when the Outside Air Temperature (OAT) is decreasing through 60°F ± 4°F (15°C ± 2°C) and opens when the OAT is increasing 2°F to 5°F (1°C to 3°C) above 60°F ± 4°F (15°C ± 2°C). Both thermostats one for each adaptor is located on a plate attached to the skin below the pilot seat. Transfer tape is used to bond the thermostats to the inside surface of the fuselage skin. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 38 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - THERMOSTATS LOCATOR TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 39 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIR INTAKE DE-ICING HEATER-ENGINE INTAKE SWITCHES The engine intake adapter heater circuit is energized when an ENGINE INTAKE switch-light on the ICE PROTECTION control panel is pushed. There is one switchlight for each engine. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 40 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ENGINE INTAKE BYPASS SWITCH-LIGHT LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 41 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIR INTAKE DE-ICING CONTROL-INTAKE HEATER RELAYS The Timer and Monitor Unit (TMU) monitors the current in the main circuit of the heater. A fault message is stored in the TMU if current below 1A or above 12A ± 0.5A, is detected. This fault message is displayed on ARCDU 1 or 2 when the TMU is interrogated by the CDS maintenance mode only. The TMU also activates the heater selection relay to energize the spare heater circuit. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 42 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - SYSTEM FUNCTIONAL SCHEMATIC TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 43 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION AIR INTAKE DE-ICING INTERFACES The Intake Air Anti-icing system is part of the aircraft ant-icing system. The TMU is the interface. The anti ice system components are: • • • • • • Intake bypass door push switches left and right OAT thermostat switches left and right Engine low oil pressure switches left and right Intake adapters left and right Heater command relays left and right Heater selection relays left and right SYSTEM TESTS The TMU monitors the current intensity to the heater and senses an abnormal current flow when the current is less than 1A or more than 12A ± 0.5A. When abnormal current is sensed, the fault message is recorded for maintenance purposes in the TMU. The TMU activates a relay to energize to the spare heater circuit. This failure is not reported or visible to the pilot. If both heating elements in the same engine adapter fail, the related ENG ADPT HEAT 1 or ENG ADPT HEAT 2 caution light on the Caution and Warning panel comes on. Other conditions that can make an adapter caution light come on are: • • • Failure of the selection relay to switch to the back-up heater Failure of the TMU module. In this case the DE-ICE TIMER and PITOT HEAT 1 or 2 caution lights also come on depending on the module TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 44 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ENGINE ADAPTER CAUTION LIGHTS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 45 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PITOT-STATIC AND ANGLE OF ATTACK PROBES ANTI-ICING SYSTEM PURPOSE Three pitot-static probes and two angle of attack vanes incorporate electrical heating elements to prevent icing. This can cause incorrect pitot or static measurements or stall protection calculations. GENERAL DESCRIPTION The Dash 8 Series 400 uses three integrated pitot and static probes. The No.1 probe is located below the pilot windshield. The No.2 probe is located below the copilot windshield. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 46 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - PRIMARY PITOT STATIC PROBE LOCATIONS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 47 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PITOT-STATIC AND ANGLE OF ATTACK PROBES ANTI-ICING SYSTEM GENERAL DESCRIPTION The No.3 standby probe is located below the bottom aft corner of the copilot side window. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 48 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - STANDBY PITOT STATIC PROBE LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 49 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PITOT-STATIC AND ANGLE OF ATTACK PROBES ANTI-ICING SYSTEM GENERAL DESCRIPTION Two Angle Of Attack (AOA) transducers are located on the forward fuselage, one under each side window. The AOA transducers are electrically anti-iced. The AOA transducer heating is automatically on as soon as 115V AC variable frequency power is available. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 50 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ANGLE OF ATTACK TRANSDUCER LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 51 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION CONTROL SWITCHES PITOT-STATIC AND ANGLE OF ATTACK PROBES The pitot-static heaters are energized before take-off using three toggle switches on the overhead console. These PITOT/STATIC PORTS switches are labelled: ANTI-ICING SYSTEM • • • SYSTEM DESCRIPTION STBY 1 2 The heaters of the Pitot-Static probes and the angle of attack transducer are monitored by the TMU. This function is performed by the three independent modules of the TMU for each of the left, right and standby Pitot-Static probes, and two different modules for the left and right angle of attack vanes. These monitoring modules have an independent power supply. The probe and AOA transducer heaters are automatically on as soon as their power supply is available. The heater power is supplied through the TMU. Power sources to the left and right Pitot-Static probes are connected directly through the control switches. The standby probe is connected through a relay, activated closed by the selection of the related control switch. The angle of attack vanes heaters are directly connected to their power supply through the TMU. The TMU checks for failure by monitoring current through the heaters. Heating of the Pitot-Static probes is controlled by three separate switches, one for each probe. These switches are located on the IRPS panel on the left overhead console. PITOT-STATIC The Left and Right 115V AC power is routed through the TMU to the Left and Right Pitot-Static probe respectively. Nominal power supply range is within 98V AC and 132V AC. The Right Essential 28V DC electrical power supply is routed through the TMU to the Standby Pitot-Static probe. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 52 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - PITOT AND STATIC PROBE SWITCH TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 53 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PITOT-STATIC AND ANGLE OF ATTACK PROBES ANTI-ICING SYSTEM CONTROLS AND INDICATIONS When the probe heater is selected on and the heater electrical current is out of specified limits, or if the heating is not activated, the TMU senses a defective heater and the respective PITOT HEAT 1, PITOT HEAT 2, or STBY PITOT caution light on the Caution and Warning Panel comes on. Fault codes are stored in the Timer Monitor Unit (TMU) for maintenance purposes. The maintenance messages associated with the fault codes are: • • • PITOT 1 FAIL PITOT 2 FAIL PITOT STBY FAIL Failure of an angle of attack vane heater or the corresponding TMU monitoring module causes a signal to be sent to the Stall Protection Module (SPM). There is no direct annunciation of heater failure on the caution panel. The failure causes one of the STALL SYST FAIL caution lights to come on. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 54 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - PITOT AND STATIC/AOA CAUTION LIGHTS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 55 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION PITOT-STATIC AND ANGLE OF ATTACK PROBES ANTI-ICING SYSTEM INTERFACES Each pitot-static probe has an internal heater element for anti-ice protection. Pitot-static heater power is routed through and monitored by the TMU. The TMU senses a defective pitot/static heater and sends the fault code to the Air Data Units (ADU). Heater failures are also recorded by the TMU for maintenance purposes. They are sent to the Central Diagnostic System (CDS) for display on the appropriate maintenance page of the Aircraft Radio Control Display Unit (ARCDU). Failures of the monitoring modules are also recorded and correspond to a different message. The TMU receives a discrete signal from the selection switch indicating the status of selection. A pitot-static probe failure detected due to the heating not being selected is not recorded as a fault for maintenance. The No.1 and 2 probes are energized with 115V AC from their related left and right variable frequency busses through 7.5A circuit breakers labelled PITOT HEAT 1 and PITOT HEAT 2. The Standby Pitot-Static probe is energized from the 28V DC Right Essential Bus. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 56 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - INSTRUMENT HEATERS MONITORING SCHEMATIC TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 57 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION PURPOSE The windshield anti-icing system prevents ice formation on the windshields and the pilot left side window. It also removes rain water from the windshields. INTRODUCTION The windshield anti-icing system has two temperature sensors per window, seven relays and two Anti-Ice Controllers (AIC). Both windshields and the pilot side window have electronically controlled heater elements laminated into the panels to keep the windows at a predetermined temperature to prevent icing and misting. The windshield wiper system removes rain water to obtain an adequate zone of vision through the windshields. The wipers are able to remove any amount of rain which may fall on the windshields during taxiing, taking off, landing and at airspeeds up to 200 kts (370.6 km/h). TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 58 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION GENERAL DESCRIPTION The pilot and copilot windshield wiper systems are symmetrical but completely independent. Each system has a two speed, DC motor fitted to a mechanical converter which drives a wiper arm and blade. A single rotary switch, located on the WINDSHIELD wiper control panel in the overhead console, operates both motor/ converters. The Windshield and Windows Ice and Rain Protection has these components: • • • • • • • • • Anti-Icing Controllers Windshield Heat Selector Pilot Side Window Switch Control Relays Windshield Wiper System Motor Assembly Wiper Arm Wiper Blade Control-Wiper Selector TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 59 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION The 115V AC phase C right bus supplies power for the copilot windshield in the NORM mode. The 115V Aphase C A right bus supplies power for the pilot side window. WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION WINDSHIELD ANTI-ICING SYSTEM The windshield anti-icing system prevents ice formation on both windshields and the pilot side window. The windows are electro-thermally anti-iced. The windshield anti-icing system includes these components: • • • • NOTE: Use caution when doing window heater and control tests, as the windshield and side windows become hot very quickly when they are heated. Prior to the removal of a faulty AIC, the appropriate circuit breaker (CB) must be pulled. Care must be taken not to remove the working AIC, as they are identical and located in close proximity to one another. Seven relays Two Anti-Ice Controllers (AIC) Windshield Heat Selector Pilot Side Window Switch The windshield anti-icing system is controlled by an overhead switch labelled HEAT located on the WINDSHIELD wiper control panel. The pilot side window anti-icing is controlled by a two-position toggle switch labelled PLT SIDE WDO/HT also located on the WINDSHIELD wiper control panel. The windshield and pilot side window heaters are controlled by the AIC. If either AIC fails, the WSHLD CTRL caution light comes on. If the HEAT selector is in the OFF position the WSHLD CTRL caution light will not come on. Failure messages are recorded in the TMU for maintenance purposes. The two maintenance messages are: • • RIGHT AIC FAIL LEFT AIC FAIL The AIC controls the related windshield heater relay. The 115V AC phase C left bus supplies power for the pilot windshield in the NORM mode. It also supplies power to both windshields in the WARM UP mode. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 60 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - FLIGHT COMPARTMENT WINDOWS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 61 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION ANTI-ICING CONTROLLERS Two AIC control heater operation to prevent ice accumulating on the windshields and the pilot side window. Both AIC activate the heaters using relays. The relays are used to isolate both AIC from the high current flow required for heating. When the windshield control is in the OFF position, the deactivation relay is controlled by the overheat temperature sensor. The activation relay stays open regardless of the normal temperature sensor information. In the WARM-UP or NORM modes, the AIC uses the normal temperature sensor information to control the activation relay. The overheat temperature sensor information is used to control the deactivation relay. The left AIC is powered by the 28V DC left secondary bus. The right AIC is powered by the 28V DC right secondary bus. The AIC are installed in the midsection of the wardrobe on the Electrical Equipment Panel (zone 225). TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 62 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - ANTI-ICE CONTROLLER LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 63 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION WINDSHIELD HEAT SELECTOR The WINDSHIELD Heat Switch controls the pilot and copilot windshield heaters. The WARM UP mode prevents thermal shocks to the windshield. To avoid this damage, the warm up relay decreases the electrical power supply to the windshield heaters by 50%. The WARM UP mode activates the warm-up relay which places both windshields in a serial connection. When WARM UP mode is selected each AIC uses the normal temperature sensor information to activate its related windshield heater. Power for the serial connection is from the pilot windshield power supply. In the OFF and NORM modes, the windshields are connected in parallel. PILOT SIDE WINDOW SWITCH The PLT SIDE WDO/HT ON/OFF toggle switch controls the pilot side window heater. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 64 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD CONTROL PANEL LOCATOR TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 65 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION CONTROL RELAYS When the pilot or copilot windshield temperature is less than 93°F ± 6°F (34°C ± 2°C) or the pilot side window temperature is less than 86°F ± 11°F (30°C ± 2°C), the related AIC energizes the activation relay that supplies 115V AC to the heater. When the windshield temperature is above 108°F ± 6°F (42°C ± 2°C) or the pilot side window temperature is above 101°F ± 7°F (38°C ± 3°C), the AIC de-energizes the relay which opens the circuit and removes the power to the heater. The overheat relays fail unpowered in the open position to prevent overheat. In the event the normal heating control fails, the AIC uses the overheat temperature sensor to control the heater. In an overheat temperature above 122°F ± 6°F (50°C ± 3°C) for windshield or above 126°F ± 6°F (52°C ± 3°C) for the pilot side window, the AIC de-energizes both relays. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 66 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - RELAY PANEL LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 67 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION CONTROLS AND INDICATIONS When the NORM mode is selected, both windshields are heated with full electrical power. When the NORM mode is selected, the WARM UP relay is de-energized and switches from a serial connection to an independent connection on the related bus. When the PLT SIDE WDO/HT switch is selected ON, the right AIC energizes the side window relay, which supplies the pilot side window heater with 115V Aphase C A right bus power. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 68 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD CONTROL PANEL TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 69 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION CONTROLS AND INDICATIONS CONTINUED A failure of either windshield heat controller causes the WSHLD CTRL caution light to come on. An overheat condition of the windshields causes the WSHLD HOT caution light to come on. An overheat condition for the pilot side window causes the SIDE WDO HOT caution light to come on. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 70 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD CONTROL AND OVERHEAT CAUTION LIGHTS TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 71 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD AND PILOT WINDOW ANTI-ICE SYSTEM TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 72 of 114 BOMBARDIER DHC 8-400 (PWC PW150) INTENTIONALLY LEFT BLANK TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 73 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION WINDSHIELD WIPER SYSTEM The wiper blades are placed into a parked position when the WIPER switch is set to the momentary PARK position. When the WIPER switch is held in the PARK position, the motor field windings are connected in series and the motors rotate at a slow speed. When the wiper arm reaches the parked position, the park switches are mechanically closed, shorting out the armatures and stopping the motors in the parked position. The WIPER switch is then released and returns to the OFF position, removing power to the motor circuits. The windshield wiper system has these components: • • • • low speed. With the WIPER switch set to HIGH, the two field winding in each motor are connected in parallel by the related switch section contacts and the motors rotate at a high speed. With the WIPER switch set to OFF from the HIGH or LOW position, electrical power is removed from the motor field windings and the wiper blades stop anywhere in their cycle. Motor Assembly Wiper Arm Wiper Blade Control-Wiper Selector The pilot and copilot windshield wiper systems are symmetrical but completely independent from each other. Each system has a two speed, DC motor fitted to a mechanical converter which drives a wiper arm and blade. A single rotary switch, located on the WINDSHIELD wiper control panel in the overhead console, operates both motor/converters. The wiper arm, with the wiper blade, is installed on the converter output shaft adjusting sleeve with a washer, nut and cotter pin. The wipers are designed to park off the windshield when not in use. The two motor/converter units are located in front of the forward pressure bulkhead. The motor/converters are independent from each other and operate the wiper arms for the pilot and copilot windshields. They are supplied with electrical power from the L and R SECONDARY buses. This configuration ensures that in the event of failure of either unit, the remaining unit will supply an unobstructed forward view for one pilot. The rotary WIPER switch on the WINDSHIELD wiper control panel operates the motor/converter units. The switch has these positions: • • • • PARK OFF LOW HIGH With the WIPER switch set to LOW, the two field windings in each motor are connected in series by the related switch section contacts and the motors rotate at a TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 74 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD WIPER MOTOR ASSEMBLY LOCATOR TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 75 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION WINDSHIELD WIPER SYSTEM WIPER ARM The wiper arm and blade are installed on the converter output shaft adjusting sleeve with a washer, nut and cotter pin. A bolt, washer, nut and cotter pin secure the adjusting sleeve in the hub arm. The wiper arm is attached to the hub and includes a tension spring. A trigger and detent within the arm facilitates removal and installation of the arm and blade assembly by keeping the blade away from the windshield. WIPER BLADE The wiper blade is attached to the arm with a nut, washers and a cotter pin. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 76 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD WIPER DETAIL TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 77 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION WINDSHIELD WIPER SYSTEM CONTROL AND INDICATIONS CONTROL-WIPER SELECTOR Both the pilot and copilot wipers are controlled by a single rotary WIPER switch. This switch is located on the WINDSHIELD wiper control panel on the overhead console with positions labelled: • • • • PARK OFF LOW HIGH The PARK position is spring-loaded to OFF. Selection of LOW or HIGH activates both wipers at the appropriate speed. Selection for LOW or HIGH to OFF stops the blades at their existing position. When the switch is held at the spring-loaded PARK position, the blades start to operate at low speed until they reach the bottom of their travel, where they automatically stop at the park position. ALTERNATE PILOT WIPER SELECTOR The alternate pilot wiper operation is controlled by the alternate action switch installed on the pilot side console. Power is supplied from the left secondary bus. When selected, the ON segment in the switch comes on, and the pilot windshield wiper operates at high speed. The relay for the system is on the flight compartment left side wall. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 78 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD CONTROL PANEL TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 79 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION WINDSHIELD AND WINDOW ICE AND RAIN PROTECTION WINDSHIELD WIPER SYSTEM DESCRIPTION The left windshield wiper system is powered from the LEFT SECONDARY bus through a 10A circuit breaker (S7) labelled PLT W/S WIPER. The right windshield wiper system is powered from the RIGHT SECONDARY bus through a 10A circuit breaker (A6) labelled COPLT W/S WIPER. The motors are grounded to the aircraft structure. The assembly has radio noise filters to suppress interference. The WIPER control selector is electrically powered from the L SECONDARY bus through a 1A circuit breaker (R7) labelled PLT WS/HT CONT. The selector is also powered from the R SECONDARY bus through a 1A circuit breaker (B6) labelled COPLT WS PLT WDO HT. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 80 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - WINDSHIELD WIPER SYSTEM SCHEMATIC TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 81 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION The propeller speed (Np) must be greater than 400 rpm for the test function to operate. PROPELLER ANTI-ICING Two advisory lights (one for each propeller) are located on the ICE PROTECTION control panel. They indicate propeller heater function. PURPOSE The Propeller Anti-Icing System has electrical heating elements in the leading edge of each propeller blade to remove ice accumulations. INTRODUCTION Ice detection is not available for the propeller anti-icing system. To avoid excessive build up of ice the pilot must select propeller heat to ON when flying through known icing conditions. When propeller heat is selected to ON, all six blades on one propeller are heated at one time, then the other propeller is heated. The propeller Anti-Icing System has these components: • • • De-icing Brush Block Bracket Assembly De-icing Timer Monitor Control Unit (TMCU) Heater Panel Control Switch CONTROL-PROPELLER HEATER SWITCH The PROP-TEST/OFF/ON, Rotary Switch controls the power to the heater. The switch is located in the flight compartment on the overhead panel. In the TEST position, the boot heaters for the No.1 propeller are cycled ON for a period of 7 seconds followed by a 2 seconds pause and then a 7 seconds ON cycle for the No.2 propeller. The test cannot be initialized again for 30 seconds to prevent overheating of the blade elements when the aircraft is on the ground. TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 82 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - PROPELLER HEATER SWITCH TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 83 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION • • • PROPELLER ANTI-ICING CONTROL-PROPELLER HEATER SWITCH Slip-rings transfer the blade heater power across the rotating/static interface using the brushes of the brush block. Three slip-rings are installed into an insulating ring contained within aluminium housing. from the receptacle, and also the connection for the two brush leads per slipring position Six brush/spring cavities Two brush/spring retaining covers A terminal housing cover The de-icing power brush block and the pulse probe that is used in the control system are attached to a bracket. The brush block is attached to the bracket at three positions. The housing is attached to the spinner back plate by a series of bolts on the outer diameter. The rings have a cross-section of 10 mm wide by 5 mm thick, with 3 mm of the thickness allowed for wear and re-facing. Also attached to the outer diameter of the housing are seven steel targets used to generate the electrical pulses for the control system pulse probe. Propeller anti-icing is powered through circuit breakers labelled PROP DEICE on the 115V AC Variable Frequency Bus. DC electrical control power is supplied directly to the left and right Timer Monitor Control Units (TMCU) through a 3A circuit breaker labelled PROP DEICE CONT and PROP DEICE 2 from the Left and Right Essential Buses respectively. BRACKET-DE-ICING BRUSH BLOCK ASSEMBLY The brush block contains the spring loaded brushes that transfers de-icing power from the airframe to the rotating propeller using slip-rings. The block is a moulded composite material with external and internal covers and contains these parts: • • • Receptacle for connection to the airframe harness Six brushes arranged with two brushes per slip-ring position, brush size 8 mm wide by 18 mm long with a length of 20 mm, and a maximum allowable length for wear of 11 mm Three terminal studs for connection of the incoming three phase power wiring TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 84 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - BRUSH BLOCK ASSEMBLY UNIT LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 85 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION is not demanded or if there is a potentially damaging failure. The TMCU controls the operation of the contactor. The contactor coil can only be enabled when the propeller heat switch is set to the ON or TEST position. PROPELLER ANTI-ICING The TMCU activates the propeller blade heaters when all of these conditions are met: DE-ICING TIMER MONITOR CONTROL The Timer Monitor Control Unit (TMCU) distributes electrical heating power to the propellers to give correct ice shedding under the different atmospheric conditions. It also monitors the propeller heaters for open or short circuits. • • • Total Air Temperature (TAT) must be at or below 41°F (5°C) Propeller is rotating (Np) greater than 400 rpm Pilots de-icing Demand switch (PDD) must be ON There is one TMCU for each propeller. Power is supplied to the heater in a cyclic sequence by the TMCU with the on time set, which weakens the ice bond and allows the lower centrifugal forces to displace the ice. The off period time allows a small layer of ice to build up and give a mass that can be shed during the on cycle. There are cooling fins on two sides of the box to dissipate the heat generated within the unit on the inner surfaces. The TMCU is cooled by air convection, conduction and radiation. The location of the TMCU in the aircraft does not allow it to be cooled by forced air. TMCU connection to the aircraft systems and propeller are by two connectors at the top of each unit. The AC power connector has these connections: • • To the aircraft AC bus through the isolator contactor To the propeller blade heaters through the brushes and slip-rings The other connects all the system switches and indicators to the Integrated Flight Cabinet (IFC) through an ARINC 429 data bus, to receive and transmit data. The TMCU has discrete solid state power switches for cycling power from a three phase variable frequency 115V AC supply to deice elements installed on the propeller blades. For safety reasons, an aircraft-mounted isolation contactor is placed between the three phase power supply from the TMCU and propeller when de-icing TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 86 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION - TIMER MONITOR CONTROL UNIT LOCATION TO BE USED FOR MAINTENANCE TRAINING PURPOSES ONLY ATA 30 - ICE & RAIN PROTECTION Issue 6 - January 2023 Page 87 of 114 BOMBARDIER DHC 8-400 (PWC PW150) ICE AND RAIN PROTECTION After approximately 30 msec the processor sends a signal to the firing control circuit to turn the solid state switches (SCR) ON and OFF and supply power to the blade heaters. PROPELLER ANTI-ICING DE-ICING TIMER MONITOR CONTROL CONTINUED The power switches are controlled by the TMCU in response to air temperature data received on an ARINC 429 Digital Information Travel System (DITS) bus. The Total Air Temperature (TAT) and propeller speed (Np) conditions are transmitted to the TMCU microprocessor by the ARINC 429 data bus from the Integrated Flight Cabinet (IFC). This output signal will be used as an input to the other TMCU on the aircraft to give synchronization of the two TMCU. This prevents both heaters from cycling ON at the same time. During the on cycle, the left