B737 NG Anti Ice & Rain

B737 NG Anti Ice & Rain

Introduction Thermal anti-icing (TAI), electrical anti-icing, and windshield wipers are the systems provided for ice and rain protection. The anti-ice and rain systems include: Flight Deck Window Heat Windshield Wipers Probe and Sensor Heat Engine Anti-Ice System Wing Anti-Ice System Ice Detection System [Option] Anti-Ice Components Diagram [Option - Ice detector probe] ELEVATOR PITOT PROBES (2 PLACES) FLIGHT DECK WINDOWS WINDOW HEAT WINDSHIELD WIPERS ALPHA VANES (2 PLACES) TEMPERATURE PROBE ICE DETECTOR PROBE ENGINE COWL LIP LEADING EDGE SLAT Page 2

Boeing B737 NG - Systems Summary [Anti Ice & Rain] Page 3

Flight Deck Window Heat [Option Window # 3 not heated] Flight deck window numbers 1, 2, 4 and 5 consist of glass panes laminated to each side of a vinyl core. Flight deck window number 4 has an additional vinyl layer and acrylic sheet laminated to the inside surface. Flight deck window number 3 consists of two acrylic panes separated by an air space. [Option Window # 3 not heated] A conductive coating on the outer glass pane of window numbers 1 and 2 permits electrical heating to prevent ice build up and fogging. A conductive coating on the inner glass pane of window numbers 4 and 5 permits electrical heating to prevent fogging. Window number 3 is not electrically heated. [Option Window # 3 heated] Flight deck windows consist of glass panes laminated to each side of a vinyl core. Flight deck window number 4 has an additional vinyl layer and acrylic sheet laminated to the inside surface. [Option Window # 3 heated] A conductive coating on the outer glass pane of window numbers 1 and 2 permits electrical heating to prevent ice build up and fogging. A conductive coating on the inner glass pane of window numbers 3, 4 and 5 permits electrical heating to prevent fogging. Flight Deck Window Heat Operation [Option Window # 3 not heated] The FWD WINDOW HEAT switches control heat to window No. 1. The SIDE WINDOW HEAT switches control heat to window number 2, 4, and 5. [Option Window # 3 not heated] Temperature controllers maintain window numbers 1 and 2 at the correct temperature to ensure maximum strength of the windows in the event of bird impact. Power to window numbers 1 and 2 is automatically removed if an overheat condition is detected. A thermal switch located on window 5 opens and closes to maintain the correct temperature of window numbers 4 and 5. [Option Window # 3 heated] The FWD WINDOW HEAT switches control heat to window number 1. The SIDE WINDOW HEAT switches control heat to window numbers 2, 3, 4 and 5. Page 4

[Option Window # 3 heated] Temperature controllers maintain windows numbers 1 and 2 at the correct temperature to ensure maximum strength of the windows in the event of bird impact. Power to window numbers 1 and 2 is automatically removed if an overheat condition is detected. Thermal switches, located on window numbers 3 and 5, open and close to maintain the correct temperature of window numbers 3, 4, and 5. Flight Deck Window Heat Schematic [Option Window # 3 heated and green lights] L WINDOW HEAT OVHT SIDE FWD FWD R SIDE PWR TEST TEMPERATURE CTROLLER TEMP CT TEMP CT TEMPERATURE CTROLLER THERMAL SWITCH L5 L4 R4 R5 L3 L2 L1 R1 R2 R3 WIND SHIELD FROM CDITIING SYSTEM WIND SHIELD CDITI: WINDOW HEAT R SIDE ED Page 5

[Option Window # 3 not heated and amber lights] L WINDOW HEAT OVHT SIDE FWD FWD R SIDE PWR TEST TEMPERATURE CTROLLER TEMP CT TEMP CT TEMPERATURE CTROLLER THERMAL SWITCH L5 L4 R4 R5 L3 L2 L1 R1 R2 R3 WIND SHIELD FROM CDITIING SYSTEM WIND SHIELD CDITI: WINDOW HEAT R SIDE ED Windshield Wipers The rain removal system for the forward windows consists of windshield wipers and a permanent rain repellent coating on the windows. CAUTI: Windshield scratching will occur if the windshield wipers are operated on a dry windshield. Page 6

Probe and Sensor Heat [Option - Captain s pitot probe on standby power] Pitot probes, the total air temperature probe and the alpha vanes are electrically heated. Static ports are not heated. When operating on standby power, only the captain s pitot probe is heated, however, the CAPT PITOT light does not illuminate for a failure. Note: The pitot probe for standby airspeed is not heated when the airplane is on standby power. Ice Detection System [Option] An advisory only ice detection system detects airplane icing in flight. The system consists of a probe located on the forward left fuselage and advisory lights located on the left forward panel. When the probe senses ice build up inflight, the ICING light illuminates. When ice has previously been detected and the probe is no longer detecting ice, the ICING light will extinguish and the NO ICE light will illuminate. The ICING light and the NO ICE light do not illuminate simultaneously. Note: Residual ice may remain on the window areas with the NO ICE light illuminated. The ICE DETECTOR light, located on the forward overhead panel, will illuminate if the ice detection system fails. Illumination of the ICE DETECTOR light also illuminates the MASTER CAUTI and ANTI ICE system annunciator lights. Engine Anti Ice System Engine bleed air thermal anti icing prevents the formation of ice on the engine cowl lip. Engine anti ice operation is controlled by individual ENG ANTI ICE switches. The engine anti ice system may be operated on the ground and in flight. Page 7

Engine Anti Ice System Operation Each cowl anti ice valve is electrically controlled and pressure actuated. Positioning the ENG ANTI ICE switches to : allows engine bleed air to flow through the cowl anti ice valve for cowl lip anti icing sets stall warning logic for icing conditions. Note: Stall warning logic adjusts stick shaker and minimum maneuver speed bars on the airspeed indicator. FMC displayed VREF is not adjusted automatically. Note: Stall warning logic, airspeed indications, and minimum maneuver speeds on the airspeed indicator return to normal when engine anti ice is positioned if wing anti ice has not been used in flight. If the cowl anti ice valve fails to move to the position indicated by the ENG ANTI ICE switch, the COWL VALVE OPEN light remains illuminated bright blue and an amber TAI indication illuminates on the CDS after a short delay. The amber COWL ANTI ICE light illuminates due to excessive pressure in the duct leading from the cowl anti ice valve to the cowl lip. ENGINE COWL ANTI-ICE (TAI) COWL COWL ANTI-ICE ANTI-ICE COWL VALVE COWL VALVE OPEN OPEN ENG ANTI-ICE COWL ANTI-ICE VALVE 5th 9th MODULATING & SHUT VALVE ENGINE BLEED VALVE 1 2 TO BLEED DUCT BLEED Page 8

Wing Anti Ice System The wing anti ice system provides protection for the three inboard leading edge slats by using bleed air. The wing anti ice system does not include the leading edge flaps or the outboard leading edge slats. The wing anti ice control valves are AC motor operated. With a valve open, bleed air flows to the three leading edge inboard slats, and is then exhausted overboard. The wing anti ice system is effective with the slats in any position. Wing Anti Ice System Operation On the ground, positioning the WING ANTI ICE switch opens both control valves if thrust on both engines is below the setting for takeoff warning activation and the temperature inside both wing distribution ducts is less than the thermal switch activation temperature. Both valves close if either engine thrust is above the takeoff warning setting or either temperature sensor senses a duct overtemperature. The valves automatically reopen if thrust on both engines is reduced and both temperature sensors are cool. With the air/ground sensor in the ground mode and the WING ANTI ICE switch, the switch remains in the position regardless of control valve position. The WING ANTI ICE switch automatically trips at lift off when the air/ground sensor goes to the air mode. Positioning the WING ANTI ICE switch to in flight: opens both control valves sets stall warning logic for icing conditions. Note: Stall warning logic adjusts stick shaker and minimum maneuver speed bars on airspeed indications. FMC displayed VREF is not adjusted automatically. Note: Stall warning logic remains set for icing conditions for the remainder of the flight, regardless of subsequent WING ANTI ICE switch position. Valve position is monitored by the blue VALVE OPEN lights. Duct temperature and thrust setting logic are disabled and have no affect on control valve operation in flight. Page 9

Wing Anti Ice System Schematic [Option - ICE DETECTOR light] L VALVE OPEN ICE DETECTOR R VALVE OPEN WING ANTI-ICE THRUST LEVERS ABOVE T.O. WARNING HIGH TEMP LOW TEMP BELOW T.O. WARNING THERMAL SWITCH GROUND -GROUND SAFETY SENSORS LEADING EDGE SLATS BLEED DUCT WING ANTI-ICE CTROL VALVE CDITI: THE GROUND WING ANTI-ICE ENGINES AT IDLE THRUST DUCT TEMPS LOW BLEED Page 10

Window Heat Panel [Option Green Lights] L SIDE WINDOW HEAT OVHT FWD FWD R SIDE PWR TEST [Option Amber Lights] FORWARD OVERHEAD PANEL L SIDE WINDOW HEAT OVHT FWD FWD R SIDE PWR TEST FORWARD OVERHEAD PANEL Window Lights Illuminated (amber) overheat condition is detected. Note: lights also illuminate if electrical power to window(s) is interrupted. Page 11

Window Heat Lights [Option Green Lights] Illuminated (green) window heat is being applied to selected window(s). Extinguished switch is, or an overheat is detected, or a system failure has occurred system is at correct temperature. Window Heat Lights [Option Amber Lights] Illuminated (amber) switch is, or an overheat is detected, or a system failure has occurred system is at correct temperature. Extinguished window heat is being applied to selected window(s). WINDOW HEAT Switches window heat is applied to selected window(s). window heat not in use. WINDOW HEAT Test Switch (spring loaded to neutral) OVHT simulates an overheat condition. PWR TEST provides a confidence test. Note: Refer to Supplementary Normal Procedures for Window Heat Test procedures. Windshield/Foot Air Controls FOOT WIND SHIELD WIND SHIELD FOOT BELOW CAPTAIN S INST PANEL BELOW F/O S INST PANEL Page 12

FOOT Controls PULL supplies conditioned air to pilots leg positions. WINDSHIELD Controls PULL supplies conditioned air to number 1 windows for defogging. Windshield Wiper Selector Panel L WIPER PARK INT LOW HIGH R WIPER PARK INT LOW HIGH FORWARD OVERHEAD PANEL Windshield WIPER Selectors PARK turns off wiper motors and stows wiper blades. INT seven second intermittent operation. LOW low speed operation. HIGH high speed operation. Probe Heat Panel [Option - Aspirated TAT] CAPT PITOT L ELEV PITOT L ALPHA VANE TEMP PROBE PROBE A B HEAT TAT TEST F/O PITOT R ELEV PITOT R ALPHA VANE AUX PITOT FORWARD OVERHEAD PANEL Page 13

Probe Heat Lights Illuminated (amber) related probe not heated. Note: If operating on standby power, probe heat lights do not indicate system status. PROBE HEAT Switches power is supplied to heat related system. power off. TAT TEST Switch [Option - Aspirated TAT] Push - Electrical power applied to TEMP PROBE on the ground. Engine Anti Ice Panel COWL ANTI-ICE COWL VALVE OPEN ENG ANTI-ICE 1 2 FORWARD OVERHEAD PANEL COWL ANTI ICE Lights Illuminated (amber) indicates an overpressure condition in duct downstream of engine cowl anti ice valve. COWL VALVE OPEN Lights Illuminated (blue) bright related cowl anti ice valve is in transit, or, cowl anti ice valve position disagrees with related ENGINE ANTI ICE switch position dim related cowl anti ice valve is open (switch ). Extinguished related cowl anti ice valve is closed (switch ). COWL ANTI-ICE COWL VALVE OPEN Page 14

ENGINE ANTI ICE Switches related engine anti ice valve is open stick shaker logic is set for icing conditions. related engine anti ice valve is closed stick shaker logic returns to normal if wing anti ice has not been used in flight. Thermal Anti Ice Indication TAI 87.7 87.7 10 0 8 2 6 4 N 1 TAI 10 8 6 4 0 2 UPPER DISPLAY UNIT Thermal Anti Ice Indications Illuminated Green cowl anti ice valve(s) open Amber cowl anti ice valve is not in position indicated by related engine anti ice switch. Page 15

Wing Anti Ice Panel [Option - ICE DETECTOR System] L VALVE OPEN ICE DETECTOR R VALVE OPEN WING ANTI-ICE FORWARD OVERHEAD PANEL Wing Anti Ice VALVE OPEN Lights Illuminated (blue) bright related wing anti ice control valve is in transit, or, related wing anti ice control valve position disagrees with WING ANTI ICE switch position dim related wing anti ice control valve is open (switch ). Extinguished related wing anti ice control valve is closed (switch ). WING ANTI ICE Switch wing anti ice control valves are closed. (in the air) wing anti ice control valves are open stick shaker logic is set for icing conditions. Note: Stick shaker logic remains set for icing conditions for the remainder of the flight, regardless of subsequent WING ANTI ICE switch position. (on the ground) wing anti ice control valves open if thrust on both engines is below takeoff warning setting and temperature inside both distribution ducts is below thermal switch activation temperature control valves close if either engine thrust is above takeoff warning setting or thermal switch is activated in either distribution duct. Switch remains switch trips at lift off. Page 16

ICE DETECTOR Light [Option - ICE DETECTOR System] Illuminated (amber) Ice detector system has failed. Icing Advisory Lights [Option - Icing Detector System] ICING P-CANCEL NO ICE P-CANCEL LEFT FORWARD PANEL ICING Light Illuminated (amber) ice detector is detecting ice light is inhibited on the ground. Press extinguishes light, if illuminated. NO ICE Light Illuminated (white) ice detector is not detecting ice, and the ice detector probe had previously detected ice light is inhibited on the ground. Press extinguishes light, if illuminated. Limitations Engine TAI must be on when icing conditions exist or are anticipated, except during climb and cruise below -40 C SAT. [Option - 737-600/-700/-800 without stiffened elevator tabs] (PRR 38506 or Service Bulletin 737-55A1080) After any ground deicing/anti-icing of the horizontal stabilizer using Type II or Type IV fluids, airspeed must be limited to 270 KIAS until the crew has been informed that applicable maintenance procedures have been accomplished that would allow exceedance of 270 KIAS. Once the applicable maintenance procedures have been accomplished, exceeding 270 KIAS is permissible only until the next application of Type II or Type IV deicing/anti-icing fluids. Page 17