Aircraft Cabin: Water System

Malaysian Institute of Aviation Technology

PASSENGER WATER

SUPPLY SYSTEM

ATA 38

Malaysian Institute of Aviation Technology Lavatory


PASSENGER WATER SUPPLY SYSTEM

ATA 38 # to supply water for drinking to galleys must be high standard of cleanliness and quality.

# for hand wash basin

# for galleys system and making hot beverages

# humiditifier

# aircond pack heat exchanger additional cooling

# water / methanol injection to engines



# Can be one or two water systems in an aircraft.

# Galleys and toilet compartments water allow to drain to atmosphere

(drain mask) or toilet waste tank

# Drain Masks are electrically heated.

# Waste water is finely atomised as it leaves the drain mask.

# Drinking water name - Potable Water:

- storage - heating - cooling (drinking fountain)

- distribution (piping and pressurized)


Passenger Water System

Malaysian Institute of Aviation Technology Lavatory



• Tank -fiberglass reinforced plastic

- older aircraft stainless steel.

• Warm air from aircond system use to prevent tank

water freezing, or fitted with an electric heater blanket

or ribbon heaters. Single phase ac supply via a CB

and thermostat(prevent over heating)

• situated below the cabin floor.

• 747 322litres 2tanks, filled from own external

passenger water service panel.


Water Tank Heating System


Water pressure control

- tank is pressurized by the engine bleed air and use an electrically driven compressor automatically start when the pneumatic pressure falls below a predetermined value.

- a paper element filter, a pressure regulator to reduce the air pressure to about 30 lbs/sq.in and a pressure relief valve.

../../../PPS for PHOTO/WATER TANK PRESSURIZATION SYSTEM.ppt


WATER SYSTEM DISTRIBUTION

- Main water distribution line runs from the tank into the space above the cabin ceiling individual supply

lines go to the galleys and toilets.

- Distribution line are usually of reinforced

plastic tubing enclosed in an aluminum

shroud to prevents leaking water dripping

on to the ceiling.

- A quick disconnect fitting is located above

each toilet and galley to allow the water

supply line to be disconnected when the

toilet or galley is to be removed.


DRINKING WATER COOLING

• Drinking fountain require cooling.

• Water temperature control at below 10 degree C by a

200V 3phase ac motor fan which will be on and drive

a fan and blows air across the Thermoelectric units

and reduce the temperature of water.

• Motor is control by Thermal Switch.

• Transformer rectifier switch is used to change the

115v ac to 28v for use by Thermo-eletric units.

• Should the control switch failed an Over Heat Switch

will break the circuit at higher temperature.


Water tank and associated line must be drained if aircraft is to be park for a long periods in cold to avoid damage caused by frozen pipes and all weather switch.

A vent valve to prevent vapor lock occurring In the wash basin taps by opening the tap lines to atmosphere.

WATER HEATING SYSTEM


Water Cooler


DRINKING WATER COOLIONG


Hot Water

Heating System


WATER HEATING

• A water heater with a capacity of about 1.7 liters is installed under each toilet sink in the supply

plumbing to the hot water tank.

• Heating the water to -

110-120 degree F(43-49degree C).

• Heater contains electrical elements inserted on the bottom of the tank.

• The heater can be isolated from the portable water system if it should require replacement.

Heater Tank has:

# on warning light # on / off control switch

# overheat reset switch # pressure relief valve.

# supply and feed connection


WATER HEATING • Heater switch on a light will illuminate and a “Cyclic

Switch” will regulate water temperature at 50 degree C.

• If “Cyclic Switch” malfunction and water reach

90 degree C the “Over Heat” switch will

operate to switch off the heater and light.

- After cooling heater can be manually reset

by pressing a button on top of the water heater.

- Reset switch cover with rubber “Bubble”.

- A core plug type pressure relief valve is fitted

to relief excessive pressure due to “Over Heat”.

- Heater can be isolated from the system for

replacement.


WATER CONTENTS GAUGE - IN GALLEY AND SERVICE PANELS

- Gallons or Litres


Water Tank Contents Measurement System


WATER CONTENTS GAUGE

• Located at lower fuselage water service panels,

attendants panels and galleys.

• Gauge feed from float and electrical transmitter.

• Transmitter is a probe which is a REED Switches,

as float/magnets moves pass a reed switch it

closes and this signal is sent to signal conditional

for transmission. (next slide)


Replenishment

• After each flight, be full or if less passenger

lesser quantity.

• To vent tank pressure air before open fill valve a

handle is pulled.

• In cold condition when aircraft need to park for

longer period/ over night water system need to

be drained to prevent fractures caused by

Frozen Lines.

• Tank with a vent valve to prevent vapour lock.


HEALTH PROTECTION

• Water System is susceptible to bacterial contamination.

• Having high standard of cleanliness during servicing

operation is important and need to apply very high

Hygiene Standards

• Once water systems has been disturbed during

maintenance it has to be sterilized.

• The Sterilize Solution ( chlorine)

is added to the flow of water during filling operation

sign of puregene in water is Milky colour with

chlorinated smell, left in system for some time

then fully flushed before water is refilled.


HEALTH PROTECTION -process

• Require disinfected at intervals as per AMM.

• After disinfected system is emptied and refilled with

Chlorinated Water

Disinfecting Passenger System

A. General.

• As per following:

A. 50 parts per million of chlorine acidified with vinegar

B. 100 PPM of chlorine - not acidified

C. 50 PPM of chlorine – not acidified

Note: Disinfection time for A & B is 1 hour. C is 4 hrs.



2. Recommended chlorine solution (concentrated)

- 50 PPM of acidified chlorine solution added to 30-

gallons water tank.

- This will minimize the objectionable taste due to

disinfectants and requires only shorter disinfecting time.

a. 9 fluid ounces(266ml) chlorine dioxide stabilized 2 %.

b. 9 fluid ounces (266ml) acetic acid(vinegar)

c. Approximately 1 gallon(4 litres) clean water.

Note: Let mixture stand for 5 minutes to complete

activity

•



B. Remove all filter cartridge from water system

and Re-installed filter cap.

- Excessive amount of disinfectant gave an

objectionable taste of chlorine water.

(A2 minimized)

C. Drain system as per AMM.


Disinfecting Aircraft Passenger Water System

D. Fill system with chlorinated water contains

50 or 100 PPM of chlorine.

1. Water chlorinated in 3 ways.

a. Concentrated chlorine solution be introduced first

and then system fill with water.

b. Concentrated chlorine mixed with drinkable water

first then pumped into system.

c. Concentrated solution may be added while

system is being filled.


SERVICING SYSTEM

• Water service point located under aircraft

fuselage below the tank.

• But away from Toilet Servicing panel.

• Water flow under pressure from Tank Rig.

• When tank reach full water overflow from

Over Flow Port or near water service panel.

• Tank draining point at bottom of system


END OF WATER SYSTEM

Aircraft Cabin: Water System

Engineering

Transcript of Aircraft Cabin: Water System