canadair chaifenqer 14-CONTENTS Page 1 Feb 12/88 TABLE OF CONTENTS Subject Page GENERAL ICE DETECTION

Transcription

1 chaifenqer ICE/RAIN PROTECTION TABLE OF CONTENTS Subject Page GENERAL ICE DETECTION WING ANTI-ICING General Operating Modes System Monitoring Lower Isolation Valve Operation ENGINE ANTI-ICING General Operation WINDSHIELD AND SIDE WINDOWS ANTI-ICING General System Controls and Indicators Operation ADS SENSORS ANTI-ICING General Operation A Figure Number LIST OF ILLUSTRATIONS Title Page 1 Anti-Iced Areas 2 Ice Detector Panel Anti-Icing Ducts and Components 4 Anti-Icing Panels and Indicators 5 Anti-Ice Control (2 Sheets) CONTENTS Page 1 Feb 12/88

2 canadsur chanencjer Figure Number Title Page 6 Overheat and Duct Fail Lights 13 7 ADS Anti-Icing Controls and Indicators CONTENTS Page 2 Apr 4/83

3 chauertqer ICE/RAIN PROTECTION GENERAL (Figures 1, 3 and 4) Anti-icing protection is provided by thermal and electrical anti-icing systems. Thermal anti-icing, using engine bleed air, protects the wing leading edges and the engine cowlings. Electrical anti-icing is provided for the windshield and the various sensors of the air data system (ADS), including the trailing vanes of the stall protection system angle-of-attack sensors. System indicators and controls are located on the centre instrument, ANTI-ICE and A.D.S. HEATER CONT panels (refer to Figure 4). ICE DETECTION (Figure 2) Icing conditions are detected by two externally mounted ice detectors. The ice detectors consist of aerodynamic struts which hold sensing probes into the airstream. The sensing probe vibrates at a set frequency until ice accumulates to a point where the frequency starts to decrease. When the frequency decreases to a value which indicates the ice has reached a certain thickness, the ice detector sends a signal to the ice detector panel in the flight compartment. The ice detector panel consists of ICE, FAIL and ICE lights for systems 1 (left ice detection system) and 2 (right ice detection system). The ICE lights at the left side of the panel receive the ice detector signals and indicate icing conditions by flashing amber (red on FAA registered aircraft). When the wing and engine anti-icing systems have been selected, white steady ICE lights come on at the right side of the panel. At the same time the flashing amber ICE lights go out. The white ICE lights go out when the ice detectors have failed to detect ice for 60 seconds. The FAIL lights come on when the built-in-test circuit detects a fault in the ice detection system or when the switch/light is pressed to test. WING ANTI-ICING (Figures 5 and 6) A. General The wing leading edge is heated with bleed air tapped from the eighth stage of each high pressure compressor. The bleed air is routed across the engine pylons and the bleed air shutoff valves and enters the bleed air manifold. Two modulating/shutoff valves, one installed on each side of the manifold, control the flow of bleed air into wing anti-icing ducts running along each side of the aircraft underfloor area to the wing leading edges. Piccolo tubes, running the full length of each leading edge, discharge the bleed air against the inside of the leading edge skin. The spanwise flow of air exhausts through exits on the lower surface of each leading edge. Page 1 Mar 01/85

4 ctiaiientjer TAT PROBE (RIGHT SIDE ONLY) PITOT STATIC HEADS Anti-Iced Areas Figure 1 Page 2 Feb 12/88

5 chaiienqer Operating Modes The system can be operated in automatic and manual modes selected by the three-position WING switch on the ANTI-ICE panel. In the automatic mode (WING switch set to AUTO), the modulating/shutoff valves are automatically controlled by an electronic anti-ice controller located in the accessory compartment on the unpressurized side of the rear pressure bulkhead. The controller compares the signals from two temperature sensors, each with temperature control and overheat detection elements, which are located inside the left and right wing leading edges, respectively. If the sensed temperature is too low, the controller opens the modulating shutoff valves to maintain the leading edge skin temperature at C ( F). When the system is operated in the manual mode (WING switch set to MAN)> both of the modulating/shutoff valves are powered to the fully open position. In this mode, the bleed air flow is not temperature-regulated and, if an overheat occurs, the modulating/shutoff valves must be closed by setting the WING switch to OFF. A separate overheat circuit in the anti-ice controller operates in both modes and transmits a warning to the flight compartment, if an overheat condition is detected by one of the overheat detection elements on the temperature sensors in the leading edge (refer to paragraph 0. System Monitoring The operation of the system is monitored by the following lights on the centre instrument and ANTI-ICE panels: - White L HEAT and R HEAT lights on the ANTI-ICE panel, which come on to indicate that the temperature of the leading edge is sufficiently high to provide efficient anti-icing. The lights are operated by associated thermal switches, designated sufficient heat switches, inside the left and right inboard wing leading edges. - Anber L FAIL and R FAIL lights which come on when a low-pressure condition exists in the associated wing anti-icing duct. The lights are controlled by pressure switches in the wing anti-icing ducts downstream of the modulating/shutoff valves. In the automatic mode of operation, the flow of bleed air into the ducts may be reduced sufficiently to lower the duct pressure to the preset warning level. In this case, a thermal switch located in each wing at WS 95, senses that the leading edge is still hot enough for effective anti-icing and prevents the associated (L or R) FAIL light from coming on. When the low-pressure condition is a true indication of a system failure, the sensed temperature is always lower than the thermal switch trip point and the associated FAIL light comes on. Page 3 Apr 4/83

6 chanenqer 1ST ICE ACCUMULATION WARNING LIGHTS When ice detector sensor probe senses ice accumulation, a signal is sent to the warning light circuit which causes the SYS 1 and SYS 2 amber (red on FAA registered aircraft) ICE lights to flash. Lights go out when wing and engine anti-icing is selected on. r ICE DETECTOR PUSH TO TEST ICE ICE SYS1 SYS2 FAIL FAIL SYS1 SYS2 ICE ICE SYS 1 AND SYS 2 FAIL LIGHTS Steady amber FAIL lights come on when built-in-test circuit detects fault in ice detection system 1 and/or 2. FAIL lights are also used as a press-to-test indication. ICE MONITOR LIGHTS Steady white ICE lights come on when wing and engine anti-icing is selected and remain on until ice detector fails to detect ice for 60 seconds. Ice Detector Panel Figure 2 p age 4 Mar 01/85

7 canaaair chanencjer A steady red L EDGEOVHT Tight on the ANTI-ICE panel and a flashing redwing ANTI-ICE/OVHT light on the centre instrument panel come on whenever an overheat condition is detected on the left or right wing leading edge* The overheat condition is detected by the overheat detection element of the affected dual-element temperature sensor and the warning signal is transmitted via the anti-icing controller to the flight compartment. If a failure occurs in the overheat warning circuits, monitoring of the leading edge skin temperature is maintained by a backup overheat sensor mounted inboard from each dual-element temperature sensor. Each sensor is wired directly to the L EDGEOVHT andwing ANTI-ICE/OVHT lights and causes these lights to come on if an overheat condition is detected in its associated wing leading edge. An amberauto FAULT light on the ANTI-ICE panel, which comes on when the anti-icing controller detects a fault in one of the overheat detection circuits caused by an open overheat detection element. A steady red DUCT FAIL light on the ANTI-ICE panel and a flashing red DUCT FAIL light on the centre instrument panel which come on when the bleed air leak detection system detects a leak in one of the wing anti-icing ducts (refer to SECTION 17, POWER PLANT for further information on the bleed air leak detection system). Lower Isolation Valve A solenoid-operated pneumatic shutoff valve, designated the lower isolation valve, is installed on the bleed air manifold downstream from the modulating/shutoff valves. In normal operation, the valve is closed to separate the two sides of the wing anti-icing system. If one of the modulating/shutoff valves fails closed, the valve is opened when theauto FAULT/ISOL OPEN switch/light on the ANTI-ICE panel is pressed. Bleed air from both of the engines is then fed through the serviceable modulating/shutoff valve. The white ISOL OPEN light comes on when the valve is open. An upper isolation valve on the bleed air manifold is opened to obtain bleed air crossfeed into the manifold from the left and right engines (refer to SECTION 17, POWER PLANT for details of valve operation and bleed air control). Operation When thewing switch is set to AUTO, the anti-icing controller controls the position of the modulating/shutoff valves. The amber L FAIL and R FAIL lights come on briefly until pressure in the wing anti-icing ducts reaches a preset minimum. The white L HEAT and R HEAT lights come on when the wing leading edges are heated to the required anti-icing temperature. Operation continues with the anti-icing controller automatically positioning the modulating/shutoff valves to maintain a constant leading edge temperature. Page 5 Apr 4/83

8 chauenqer Anti-Icing Ducts and Components Figure 3 Page 6 Feb 12/88

9 chaiienper The lower isolation valve is normally left in the closed position (ISOL OPEN light out) when the system is in the automatic mode. The system requires only occasional monitoring for overheat conditions (L EDGE OVHT light on) or overheat detection faults (AUTO FAIL light on). If either of these abnormal conditions is detected, the system must be operated in the manual mode (WING switch set to MAN) with the lower isolation valve open. In the manual mode, the modulating/shutoff valves are set to the fully open position and the system must be monitored frequently to prevent prolonged operation with a leading edge overheat. If an overheat condition occurs, the WING switch must be set to OFF until the L EDGE OVHT light goes out. If a bleed air leak occurs in one of the wing anti-icing ducts, the DUCT FAIL lights on the ANTI-ICE and centre instrument panels come on. If the leak in the duct is sufficiently large to reduce the duct pressure below the preset minimum, the appropriate (L or R) FAIL light also comes on. ENGINE ANTI-ICING (Figure 5) A. General Engine anti-icing is obtained by heating the leading edge of the nose cowl with compressor eighth-stage bleed air. The bleed air is ducted to the lower left side of each engine via left and right pressure regulating valves and enters a ring-shaped piccolo tube inside each nose cowl. The air discharges from the piccolo tube against the inside surface of the cowl leading edge and exhausts through slots in the cowl assembly. The solenoid-operated pressure regulating valves are energized to the closed position. This feature causes the valves to fail open following an electrical failure. The system is controlled by the ENGINES, LEFT and RIGHT switch/lights on the ANTI-ICE panel. When the switch/lights are pressed in, the pressure regulating valves are de-energized and forced open under bleed air pressure.* When the switch/lights are pressed out, the valves are energized closed. Each switch/light has a white ON and an amber FAIL light. The ON light comes on whenever the switch/light is pressed in or whenever the associated pressure regulating valve fails open. A pressure switch in the duct downstream from the associated pressure regulating valve, causes the FAIL light to come on if the switch/light is pressed in and a low pressure condition exists. The FAIL light also comes on when the switch/light is pressed out and the pressure regulating valve fails in the open position. Page 7 Apr 4/83

10 chaiiencjer EFFECTIVITY Ujj Aircraft incorporating SB For other A/C, refer to Figure 5. o WING ANTI-ICE OVHT WING ANTNCE/OVHT LIGHT WING MAN ANTI-ICE WSHLD LOW LOW m OFF AUTO FIF/ML] 11 R FAIL 1 ENGINES 1 PUSH ON/OFF LEFT RIGHT FAIL I L LJ i i FAIL Ijl 0N III HIGH HIGH NOHT I NOHT! TEST ; TEST ILHEATI 1 DUCT 1 1 AUTO I! FAIL 1 FAULT RHEAT! LEDGE 1 ISOL TEST j OVHT 1 OPEN L..JJ I LEFT L-RiGHT-J Q) PUSH OPEN/CLOSED J ANTI-ICE CONTROL PANEL n DUCT FAIL DUCT FAIL TEST SWITCH PITOT HEAT PITOT HEAT LIGHT ADS HEATER CONTROL PANEL O Anti-Icing Panels and Indicators Figure 4 Page 8 Feb 12/88

11 ctiaiiencjer B. Operation When engine anti-icing is required, the ENGINES, LEFT and RIGHT switch/lights are pressed in- The white ON lights come on and the pressureregulating valves open allowing bleed air to enter the nose cowl piccolo tubes. The valves regulate the air flow to maintain a pressure of 55 ± 3 psi at the piccolo tube inlets. When the switch/lights are pressed in, the amber FAIL lights come on momentarily until the anti-icing air pressure increases to above 10 psi. When engine anti-icing is no longer required, the switch/lights are pressed out to close the pressure-regulating valves, and the white ON lights go out. The sixth-stage bleed air system, used to provide anti-icing for the engine splitter rings and inlet guide vanes, is also controlled by the ENGINES, LEFT and RIGHT switch/lights and uses the same monitoring and fault indications (refer to SECTION 17, POWER PLANT, for details of this system). WINDSHIELD AND SIDE WINDOWS ANTI-ICING (Figure 5) A. General The windshields and side windows are of laminated construction and each has a thin heating element between the two outer laminations for defogging and anti-icing. Each windshield is also equipped with a windshield icing detector/indicator. B. System Controls and Indicators The left and right sides of the system operate independently and are controlled by the WSHLD, L and R (WINDSHIELD, LEFT and RIGHT on aircraft not incorporating Canadair Service Bulletin ) switches on the ANTI-ICE panel and temperature controllers located under the left and right side consoles. The temperature controllers monitor temperature sensors, one for normal operation and one spare, integral with each windshield and side window. Amber NO HT lights on the ANTI-ICE panel indicate system faults and a PRESS TO TEST pushbutton on the same panel is used to test the temperature controller circuits. Page 9 Feb 12/88

12 chanerujer WING ANTI-ICE SWITCH Three-position switch controls mode of operation of modulating/shutoff valves. AUTO - Anti-icing controller operates modulating/shutoff valves to maintain constant wing leading edge temperature. MAN - Anti-icing controller bypassed and modulating/shutoff valves set to fully open position. Bleed air flow is not regulated to maintain a specific leading edge temperature. OFF - Modulating/shutoff valves closed. ENGINES - LEFT AND RIGHT SWITCH/LIGHTS Control operation of pressure regulating valves of engine antiicing system. When switch/lights are pressed in, valves de-energize and open. When pressed out. valves are energized and close. ON light - white light comes on when switch/light is pressed in or when associated pressure regulating valve fails open. FAIL light - amber light comes on when switch/light is pressed in and bleed air pressure is low or when switch/light is pressed out and associated pressure regulating valve fails open. ANTI-ICE OFF L AND R FAIL LIGHTS Amber L or R FAIL light comes on if low pressure condition is detected in associated wing anti-icing duct. L AND R HEAT LIGHTS White L or R HEAT light comes on to indicate that temperature of associated leading edge is high enough for effective anti-icing. DUCT FAIL AND L EDGE OVHT LIGHTS AUTO ENGINES LEFT RIGHT 1 L FAIL! Hi FAIL 1 11 R FAIL 1 1 III ON L, PUSH ON/OFF -1 L HEAT] 1 G R HEAT 1 DUCT I FAIL LEDGE 1 1 0VHT FAIL 1 N II 1 AUTO t FAULT tsol 1 OPEN 1 PUSH ON/OFF Red DUCT FAIL light comes on when overheat condition due to duct failure is detected in area around wing anti-icing ducts. Amber L EDGE OVHT light comes on when overheat condition is detected on left or right wing leading edge. AUTO FAULT/ISOL OPEN SWITCH/LIGHT Split legend switch/light controls operation of lower isolation valve. Valve opens when switch/light pressed in; closes when switch/light pressed out. EFFECTIVITY Itjj Aircraft incorporating SB ISOL OPEN light - white light comes on when lower isolation valve is open. AUTO FAULT - amber light comes on when anti-icing controller detects an open overheat sensor in one of the overheat detection circuits. [11 Aircraft not incorporating SB Anti-Ice Control Figure 5 (Sheet 1) Page 10 Feb 12/88

13 ctianenper WINDSHIELD LEFT AND RIGHT CONTROL SWITCHES (2) WSHLD SWITCHES (2) Three-position switches control same side windshield and side window heating elements. HIGH or LOW - Temperature control units maintain windshield and side window at constant temperature. At HIGH setting, controlled temperature of windshield is higher than controlled temperature at LOW setting. Controlled temperature of side window is the same at HIGH or LOW. Control the heating elements for the windshield and side windows. ON - Power is supplied to heating elements via the temperature heat controllers. Temperature is controlled to 58 C (136 F) for the windshield and 41 C O06 F) for the side window as sensed by temperature sensors. OFF/RESET - System is reset after test of shutdown. ANTI-ICE AUTO 1 LFAIL 1 R FAIL [LHEAT R HEAT ENGINES 1 PUSH ON/OFF LEFT RIGHT FAIL j 1 ON j 1 FAIL 1 i ON III 1 DUCT 1 1 AUTO I 1 FAIL FAULT 1 LEDGE ISOL j OVHT j 1 OPEN 1 PUSH OPEN/CLOSED NO HT LIGHTS (4) Amber NO HT light comes on if associated temperature control unit detects an electrical fault in heating circuit. TEST LIGHTS (4) Green TEST lights come on during system test to indicated operation of associated heating circuit. TEST BUTTON If WSHLD switches are set to HIGH, all four heating circuits are tested when button is pressed. Correct operation of the system is indicated if all four green TEST lights come on for at least one second. PRESS TO TEST PUSHBUTTON Used to test all windshield and side window heating circuits. EFFECTIVITY LU Aircraft incorporating SB ^U Aircraft not incorporating SB Anti-Ice Control Figure 5 (Sheet 2) Page 11 Feb 12/88

14 canaaair cftaiiencjer Operation When the WSHLD switches are set to HIGH or LOW, the temperature controllers monitor their associated temperature sensors and control power to the heating elements to maintain the windshields and the side windows at a constant temperature (HIGH selects a higher controlled temperature for the windshields only). On aircraft not incorporating Canadair Service Bulletin , when the WINDSHIELD, LEFT and RIGHT switches are set to ON, the temperature controllers monitor their associated temperature sensors and control power to the heating elements to maintain the windshields at 58 C (136 F) and the side windows at 41 C (106 F). The affected heating circuit is de-energized and the appropriate NO HT light comes on if any of the following faults occur: - A windshield or side window overtemperature - A shorted temperature sensor - An overcurrent condition - No current flow when a controller is commanding power - Current flow when a controller is commanding no power - A loss of input power (ac or dc) to the system. With the WSHLD, L and R (WINDSHIELD, LEFT and RIGHT) switches set to HIGH (on), when the TEST (PRESS TO TEST) pushbutton is pressed, the circuits in the temperature controllers are independently tested (each controller has two control circuits: one for the windshield and one for the side window). If the circuits are operating correctly, the appropriate green TEST lights on the ANTI-ICE panel come on for at least one second. After testing, the WSHLD, L and R (WINDSHIELD, LEFT and RIGHT) switches must be set to OFF/RESET before normal operation can be restored. The windshield icing detectors/indicators consist of small, red, light beams aimed at the bottom of the windshields. These beams pass through the windshields and are not visible under ice-free conditions. When ice formation begins, light is reflected and is displayed as a red area of approximately one-half inch diameter. The detectors/indicators come on whenever the battery bus is energized. Page 12 Feb 12/88

15 ADS SENSORS ANTI-ICING (Figure 7) A. General canadair chauenper The ADS sensors anti-icing system consists of heating elements in the left and right pi tot heads, left and right static ports, left and right angle-of-attack (AOA) vanes, and the total air temperature (TAT) probe. Power to the elements is controlled by a rotary PWR & METER SELECT switch located on the ADS HEATER CONT panel. The switch is also provided to test the individual heater elements in conjunction with a 1 HTR CURRENT indicator. B. Operation When the PWR & METER SELECT switch is moved away from the HTRS OFF position, power is applied to all the heating elements. If a heater fails in the left or right AOA vane, the left or right static port, or the TAT probe, an amber HTR FAIL light on the ADS heater control panel comes on. If this occurs, the switch must be rotated through all positions until the fault is detected by the HTR CURRENT indicator indicating a red zone. The HTR FAIL press to reset switch/light must then be pressed to put out the warning light. The failure indicating system automatically resets to indicate further failures if they occur. Page 12A Feb 12/88

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17 ctianenejer ^ W ZUC Q o WING ANTI-ICE WING ANTI-ICE/OVHT LIGHT Flashing red OVHT light comes on with L EDGE OVHT light on ANTI-ICE panel when overheat condition exists on left or right leading edge. When pushed to test, OVHT light comes on flashing and L EDGE OVHT light on ANTI-ICE panel comes on. ZERO V ) MLG BAY 1 D OE V* 1 " HE TC T OVHT lovht III WARN FAIL PUSH TO TEST o (r^snj o DUCT FAIL LIGHT Flashing red DUCT FAIL light comes on if bleed air leak is detected by sensors of bleed leak detection system (refer to SECTION 17, Figure 11). If wing anti-icing ducts are affected, red DUCT FAIL light on ANTI-ICE panel also comes on. When pushed to test, light comes on flashing and DUCT FAIL lights on ANTI-ICE and BLEED AIR panels come on. Overheat and Duct Fail Lights Figure 6 Page 13 Mar 01/85

18 chaiienqer Amber PITOT HEAT lights, located on the pilot's and copilot's instrument panels, are provided to indicate a failure of the left (pilot's) or right (copilot's) pitot static head heater. In this case, the system cannot be reset. When the PWR & METER SELECT switch is selected to HTRS OFF, the HTR FAIL light and the PITOT HEAT lights come on, and the HTR CURRENT indicator indicates in the red zone. Page 14 Apr 4/83

19 canatlair chaiientjer PWR & METER SELECT SWITCH HTR FAIL SWITCH/LIGHT Amber HTR FAIL light comes on if a heater fails in the left or right AOA vane, left or right static port, or the TAT probe. When pressed in, light goes out and system is reset to receive any further failures. Controls power to heating elements in the left and right pitot heads, left and right static ports, left and right AOA vanes, and the TAT probe. When set away from HTRS OFF, ail heating elements are supplied. Also used to test individual heater elements. % HTR CURRENT INDICATOR indicates heater current in terms of percentage. Red zone indicates failed system. PITOT HEAT LIGHTS Amber PITOT HEAT lights come on to indicate failure of associated pitot static head, heater. Pilot's light signals failure of left heater; copilot's light signals failure of right heater. ADS Anti-Icing Controls and Indicators Figure 7 Page 15 Apr 4/83