b737-300/400 anti ice

of 30PT. METRO BATAVIAPT. METRO BATAVIADirectorate of OperationalDirectorate of Operational

737-300/400737-300/400ANTI-ICEANTI-ICE

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Anti-Ice Protection Areas

The cowl lip on both engines are heated utilizing bleed air.

Both elevator pitot tubes (one on each

side of vertical stabilizer) are

electrically heated.

All six leading edge slats (three on each wing) are

heated utilizing bleed air.

All four pitot-static tubes (two on

each side), both AOA vanes (one

on each side) and the TAT probe (left

side only) are electrically heated.

Eight of the ten flight deck windows are electrically heated.


Window Heat PanelWindow Heat Panel



Window OVERHEAT Lights:Window OVERHEAT Lights:Illuminated –Illuminated –Overheat condition is detected.Overheat condition is detected.Temp reaches 62 degree celciusTemp reaches 62 degree celcius

Note: OVERHEAT light illuminates Note: OVERHEAT light illuminates if electrical power to window is if electrical power to window is interrupted.interrupted.



Window Heat ON Lights:Window Heat ON Lights:Illuminated –Illuminated –Window heat is being applied to Window heat is being applied to selected window. Under normal selected window. Under normal conditions, all four green ON lights conditions, all four green ON lights should illuminate when the WINDOW should illuminate when the WINDOW HEAT switches are positioned to ON.HEAT switches are positioned to ON. Range working temperature 32-43 degree Range working temperature 32-43 degree celciuscelcius

Extinguished –Extinguished –One of the following has occurred:One of the following has occurred:• The respective switch has been The respective switch has been

turned OFF.turned OFF.• An overheat condition has been An overheat condition has been

detected.detected.• A system failure has occurred.A system failure has occurred.• The respective window is already The respective window is already

above it normal operating temperature.above it normal operating temperature.



WINDOW HEAT Switches:WINDOW HEAT Switches:ON –ON –Window heat is applied to selected Window heat is applied to selected window.window.

OFF –OFF –Window heat not in use.Window heat not in use.



WINDOW HEAT Test Switch:WINDOW HEAT Test Switch:(spring-loaded to center)(spring-loaded to center)OVHT –OVHT –Tests the window overheat system by Tests the window overheat system by simulatingsimulating an OVERHEAT condition. an OVERHEAT condition.

PWR TEST –PWR TEST –Provides a confidence test. Use PWR Provides a confidence test. Use PWR TEST whenever one or more green ON TEST whenever one or more green ON lights lights do notdo not illuminate when the illuminate when the WINDOW HEAT switches are positioned WINDOW HEAT switches are positioned to ON. to ON.


Window/Foot Air ControlsWindow/Foot Air Controls

WINDSHIELD AIR Controls:WINDSHIELD AIR Controls:Pull –Pull –Supplies conditioned air to respective Supplies conditioned air to respective forward windows (L1 and R1) for forward windows (L1 and R1) for defogging.defogging.

FOOT AIR Controls:FOOT AIR Controls:Pull –Pull –Supplies conditioned air to pilots’ leg Supplies conditioned air to pilots’ leg positions.positions.


Pitot-Static Heat PanelPitot-Static Heat Panel



PITOT STATIC Lights:PITOT STATIC Lights:Illuminated –Illuminated –Related probe not heated.Related probe not heated.

Extinguished –Extinguished –Related probe is receiving heat.Related probe is receiving heat.



PITOT STATIC HEAT Switches (A and PITOT STATIC HEAT Switches (A and B):B):ON –ON –Power is supplied to electrically heat Power is supplied to electrically heat related probe. Respective pitot-static related probe. Respective pitot-static light will extinguish to indicate heat is light will extinguish to indicate heat is being applied.being applied.

OFF –OFF –Power is removed from related probe.Power is removed from related probe.


Engine Anti-Ice PanelEngine Anti-Ice Panel


Engine Anti-Ice PanelEngine Anti-Ice PanelCOWL ANTI-ICE Lights:COWL ANTI-ICE Lights:Illuminated –Illuminated –Indicates an overpressure or Indicates an overpressure or overtemperature condition in the duct overtemperature condition in the duct downstream of the engine cowl anti-downstream of the engine cowl anti-ice valve.ice valve.Over pressure >65 PSIOver pressure >65 PSIOver temperature >825 degree F Over temperature >825 degree F


Engine Anti-Ice PanelEngine Anti-Ice PanelCOWL VALVE OPEN Lights:COWL VALVE OPEN Lights:Illuminated Illuminated brightbright blue – blue –Related engine cowl anti-ice valve is in Related engine cowl anti-ice valve is in transit, or related engine cowl anti-ice transit, or related engine cowl anti-ice valve position disagrees with related valve position disagrees with related ENG ANTI-ICE switch position.ENG ANTI-ICE switch position.

Illuminated Illuminated dimdim blue – blue –Related engine cowl anti-ice valve is Related engine cowl anti-ice valve is fully open and therefore in agreement fully open and therefore in agreement with ENG ANTI-ICE switch position with ENG ANTI-ICE switch position (switch ON). Normal pressure 50 PSI(switch ON). Normal pressure 50 PSI

Extinguished –Extinguished –Related cowl anti-ice valve is closed Related cowl anti-ice valve is closed (switch OFF).(switch OFF).


Engine Anti-Ice PanelEngine Anti-Ice PanelENGINE ANTI-ICE Switches:ENGINE ANTI-ICE Switches:ON –ON –Related engine cowl anti-ice valve is Related engine cowl anti-ice valve is signaled to open.signaled to open.

OFF –OFF –Related engine cowl anti-ice valve is Related engine cowl anti-ice valve is signaled to close.signaled to close.


Wing Anti-Ice PanelWing Anti-Ice Panel


Wing Anti-Ice PanelWing Anti-Ice PanelWing Anti-Ice (L & R) VALVE OPEN Lights:Wing Anti-Ice (L & R) VALVE OPEN Lights:Illuminated Illuminated brightbright blue – blue –Related wing anti-ice valve is in Related wing anti-ice valve is in transit, or transit, or related wing anti-ice related wing anti-ice valve position valve position disagrees with WING ANTI-ICE switch disagrees with WING ANTI-ICE switch position.position.

Illuminated Illuminated dimdim blue – blue –Related wing anti-ice valve is fully open and Related wing anti-ice valve is fully open and therefore in agreement with WING ANTI-ICE therefore in agreement with WING ANTI-ICE switch position (switch ON). Max switch position (switch ON). Max temperature 257 degree F / 125 degree Ctemperature 257 degree F / 125 degree C

Extinguished –Extinguished –Related wing anti-ice valve is closed Related wing anti-ice valve is closed (switch OFF).(switch OFF).


Wing Anti-Ice PanelWing Anti-Ice PanelWING ANTI-ICE Switch:WING ANTI-ICE Switch:OFF –OFF –Both wing anti-ice valves are signaled Both wing anti-ice valves are signaled to close.to close.

ON (in flight) –ON (in flight) –Both wing anti-ice valves are signaled Both wing anti-ice valves are signaled to open.to open.

ON (on the ground) –ON (on the ground) –• Both wing anti-ice valves are signaled to Both wing anti-ice valves are signaled to open open ifif both thrust levers are below the both thrust levers are below the takeoff warning setting takeoff warning setting andand temperature temperature inside both distribution ducts is below inside both distribution ducts is below thermal switch activation temperature.thermal switch activation temperature.• Both wing anti-ice valves are signaled to Both wing anti-ice valves are signaled to close close ifif either thrust lever is above the either thrust lever is above the takeoff warning setting takeoff warning setting oror the thermal the thermal switch is activated in either distribution switch is activated in either distribution duct. Switch remains in ON position.duct. Switch remains in ON position.• Switch automatically moves to OFF upon Switch automatically moves to OFF upon air/ground system sensing “air” mode.air/ground system sensing “air” mode.

This concludes the review of the This concludes the review of the Anti-Ice Panels. The remainder of the Anti-Ice Panels. The remainder of the

presentation will discuss the anti-ice system presentation will discuss the anti-ice system in greater detail. Click in greater detail. Click NextNext to continue. to continue.


Window Heat

L4L5R4 R5

L1L2L3

R1R2 R3Captain’s

forward windowFirst Officer’s forward window First Officer’s

side windowCaptain’s

side window

Captain’s overhead windowsFirst Officer’s overhead windows

Temperature controllers maintain the forward (L1, R1) and side windows (L2, R2) at the correct temperature to ensure maximum strength of the windows in the event of a bird strike. Power to the forward and side windows is automatically removed if an overheat condition is detected. A thermal switch attached to the aft overhead windows (L5, R5). This thermal switch opens and closes to maintain the correct temperature of the overhead windows (see schematic next slide). Windows L3 and R3 are not electrically heated.


Window Overheat TestWindow Overheat TestUse the OVHT test to simulate an overheat condition of the window heat system. This test will ensure Use the OVHT test to simulate an overheat condition of the window heat system. This test will ensure that window overheat protection is operating normally.that window overheat protection is operating normally.

Click here to see a demonstrationClick here to see a demonstrationof the OVHT testof the OVHT test


Window Heat Power TestWindow Heat Power TestUse PWR TEST whenever one or more green ON lights Use PWR TEST whenever one or more green ON lights do notdo not illuminate when the WINDOW HEAT illuminate when the WINDOW HEAT switches are positioned to ON. This will provide a confidence test to ensure that the window heat system switches are positioned to ON. This will provide a confidence test to ensure that the window heat system is operating normally. is operating normally.

Click here to see a demonstrationClick here to see a demonstrationof the PWR TESTof the PWR TEST


Window Heat Schematic

L1 R1 R2 R3L2L3

L5 L4 R4 R5

VENTED TOFLIGHT DECK

VENTED TOFLIGHT DECK

THERMAL SWITCH

WIND-SHIELD

AIR

WIND-SHIELD

AIRFROMAIR CONDITIONING

SYSTEM

TEMPERATURE CONTROLLER

TEMPERATURE CONTROLLER

TEMP CONT

TEMP CONT


Pitot-Static Probe and Sensor HeatPitot-Static Probe and Sensor Heat

See picture of pitot-static See picture of pitot-static probes associated probes associated with lights abovewith lights above

See picture of pitot-staticSee picture of pitot-static probes associatedprobes associatedwith lights above with lights above

All pitot-static probes, the total temperature probe (TAT PROBE), and the angle of airflow sensors All pitot-static probes, the total temperature probe (TAT PROBE), and the angle of airflow sensors (L, R ALPHA VANE) are electrically heated to prevent the formation of ice. The two alternate static (L, R ALPHA VANE) are electrically heated to prevent the formation of ice. The two alternate static ports are not heated.ports are not heated.

See picture of alternateSee picture of alternatestatic port static port


Engine Anti-IceThe engine anti-ice system utilizes bleed air from the 5th or 9th stage of the high pressure compressor section. Only the engine cowl lip is anti-iced. The cowl anti-ice valve is electrically activated and pneumatically operated. Positioning the respective ENG ANTI-ICE switch to ON allows engine bleed air to flow through the cowl anti-ice valve to the cowl lip. While the cowl anti-ice valve is transitioning from closed to open, the COWL VALVE OPEN light illuminates bright blue. When the cowl anti-ice valve is fully open, the COWL VALVE OPEN light illuminates dim blue.

Engine bleed air

valve

To pneumaticsystem

Cowlanti-icevalve

9th

stage

5th

stage

Highstage valve

(9th)

No. 1 engine

See picture ofSee picture ofengine cowl lipengine cowl lip


Engine Anti-IceIf the cowl anti-ice valve fails to move to the position selected by the ENG ANTI-ICE switch, the COWL VALVE OPEN light remains illuminated bright blue. The amber COWL ANTI-CE illuminates to indicate excessive pressure or temperature in the duct leading from the cowl anti-ice valve to the cowl lip. Engine anti-ice is available to the cowl lip even when the engine bleed air valve is closed. For example, during a BLEED TRIP, the engine bleed air valve is automatically signaled to close. This closure will not affect engine anti-ice availability for the respective engine.

Engine bleed air

valve

To pneumaticsystem

Cowlanti-icevalve

9th

stage

5th

stage

Highstage valve

(9th)

No. 1 engine


Wing Anti-IceThe wing anti-ice system utilizes bleed air to protect the leading edge slats only. The wing anti-ice system does not include the leading edge flaps (Krueger flaps). The wing anti-ice valves are AC motor operated. With a valve open, bleed air flows to the leading edge slats via a telescoping duct. The bleed air is then exhausted overboard through small exhaust holes located on the lower surface of the slats. The wing anti-ice system is effective with the slats in any position (fully retracted, extended, or fully extended).

Leading Edge Flaps

(not heated)

Leading Edge Flaps

(not heated)

Leading Edge Slats

Leading Edge Slats


Wing Anti-IceSystem operation on the ground: Positioning the WING ANTI-ICE switch to ON, signals the two (left & right) wing anti-ice valves to open. The valves will open if the thrust levers on both engines are below the setting for takeoff warning activation (approximately 32° thrust lever angle) and the temperature inside both wing distribution ducts is less than the thermal switch activation temperature. While the valves are transitioning from closed to open, the associated VALVE OPEN light will illuminate bright blue, and then illuminate dim blue when the respective valve is fully open.

Leading Edge Flaps

(not heated)

Leading Edge Flaps

(not heated)

Leading Edge Slats

Leading Edge Slats


Wing Anti-IceSystem operation on the ground (continued): Both wing anti-ice valves are signaled to close if either thrust lever is above the setting for takeoff warning activation or the temperature inside either wing distribution duct senses over-temperature. In the event that the valves do close, the associated VALVE OPEN light illuminates bright blue to indicate disagreement between switch and valve position (WING ANTI-ICE switch remains in the ON position). The valves automatically re-open when both thrust levers are repositioned below the setting for takeoff warning activation and both temperature sensors are cool. VALVE OPEN lights now illuminate dim blue to indicate agreement between switch and valve position.

Leading Edge Flaps

(not heated)

Leading Edge Flaps

(not heated)

Leading Edge Slats

Leading Edge Slats


Wing Anti-IceSystem operation in flight: During takeoff, when the air/ground sensing system detects being airborne, the WING ANTI-ICE switch automatically trips to the OFF position, which will result in the VALVE OPEN lights changing from bright blue to extinguished. The extinguishing of the VALVE OPEN lights indicate that the wing anti-ice valves are now fully closed, which is in agreement with the WING ANTI-ICE switch (OFF). Once in flight, thrust lever setting logic and distribution duct temperature are inhibited and have no affect on wing anti-ice valve operation, therefore both valves open when the WING ANTI-ICE switch is positioned to ON.

Leading Edge Flaps

(not heated)

Leading Edge Flaps

(not heated)

Leading Edge Slats

Leading Edge Slats


Wing Anti-Ice Schematic

TELESCOPING DUCT

LEADING EDGE SLATS

PNEUMATICMANIFOLD

WING ANTI-ICEVALVE

WING DISTRIBUTION DUCT

RIGHTMAIN

LANDINGGEAR

GROUND

AIR

HIGHTEMP

LOWTEMP

THRUST LEVERS ABOVE T/O WARNING THRUST LEVERS BELOW T/O WARNING

THERMALSWITCH

b737-300/400 anti ice

Engineering