Cabin Interior System: Lavatory

Malaysian Institute of Aviation Technology AIRCRAFT TOILET/ LAVATORY SYSTEM

Malaysian Institute of Aviation Technology

AIRCRAFT TOILETS


AIRCRAFT TOILET/ LAVATORY SYSTEM

Introduction

• Types of Toilets

• Removable Toilet/Elsan Toilet

• Reusable Liquid Flush Type

• Vacuum Toilet • Toilet Equipments

• Miscellaneous equipment

• Dispenser equipment

• Disposal equipment • Toilet Ventilation System

• Venturi

• Check valve

• Muffler

• Restrictors • Corrosion Control


Removable Toilet

- Fitted on small aircraft, short range a/c.

- simplest type called an Elsan toilet

- Storage bin is refilled with correct amount of

disinfectant (Raquasan).

- Whole unit is removed when

dispose off contents.

- Secured by quick release

method.


REMOVABLE TOILETS / ELSAN TOILET


Reusable Liquid Flush Type


Vacuum Toilet System


Lavatory


LAVATORY INTRODUCTION

• Number and type of toilets varies

according to the size and type of aircraft

• Toilet compartment constructed as modules be easily removed from the aircraft, made from glass fiber honeycomb having

a decorative finish.



• Toilet is illuminated by lights in the ceiling.

- lights is automatically dim when the

door is open, and come on bright when

the door is closed and locked, actuated

by door lock switches.

- If all the toilets in that group are occupied

the appropriate cabin sign is illuminated.

- Smoking is not permitted.

LAVATORY INTRODUCTION


Lavatories are modular, self contained

units each has this equipment:

* Air sickness bag and sanitary napkin dispenser

* Ashtray (interior and exterior)

* Assist handle

* Attendant call button and reset switch

* Coat hook

* Diaper changing table (some installations)

* Dual roll toilet paper holder

* Facial tissue dispenser


• lavatories are modular, self contained units each has this equipment:

* Fire extinguisher(in waste compartment)

* Flushing toilet, with toilet seat and cover

* Non-glass mirror (shatter resistant)

* Handicap assist rails (some installations)

* Information and instruction placards

(including NO SMOKING sign)

* Light switches

* Oxygen masks (2)


Lavatory



Removing Waste

Service Vehicle Adaptor

http://www.airport-technology.com/contractors/groundequipment/combi_box/combi_box5.html


AIRCRAFT TOILETS


• Is ventilated by allowing pressurized

cabin air to escape to atmosphere.

• Toilet compartment are vented by air flowing

through a gap between the toilet shroud and the

toilet bowl flange, and into the vent duct located

beneath the toilet shroud.

LAVATORY VENTING SYSTEM

../PPS for PHOTO/schematic of galley and toilet ventilation system.ppt



TOILET VENTILATION SYSTEM

System consists of the following components.

1.Venturi – limits the outflow of cabin air when aircraft

is pressurized.

2.Check Valve – prevents back flow through the

ventilation system.

3.Muffler – reduce duct noise in the galley ventilation

system.

4.Galley vent Inlet – picking up galley odor.

5.Restrictors – These balance the airflow between

galley units and toilet compartment.


FIRE PRECAUTIONS – TOILETS IN AIRCRAFT OVER 5700 kg MTWA

• Airworthiness Notice No.32 requires that all lavatory waste containers, provided for flammable materials must be inspected regularly to ensure that all entry flaps or doors operate, seal and latch correctly. Containers for used towels, papers and waste, are made from materials resistant to fire.

• Smoking is not permitted in toilet compartment.


CABIN AND TOILET FIRE PROTECTION – AIRCRAFT OVER 5700 kg MTWA

• Airworthiness Notice no. 32 requires a smoke detector in each toilet compartment.

• Smoke detector must operate a warning light and or aural warning in the passenger cabin, also operate a warning light on the flight deck.

• It is recommended that built in the fire extinguishers be fitted in each toilet waste container, also a fire access points be built into toilet waste containers. This is to ensure efficient distribution of extinguisher from hand held fire extinguishers.

( BCF type )


Malaysian Institute of Aviation Technology LIQUID FLUSH TOILETS


LIQUID FLUSH TOILETS

- Common type of toilet in passenger aircraft

- self contained, waste collection tank

mounted directly below the toilet bowl.

- Material Stainless steel bowl

tank stainless steel or fiber-glass Laminate.

- Capacity 20 gallons, fill with pre-charge

of strong disinfectant chemical (Raquasan),

dye and deodorant and can be used

till 100 times.



It consist of seat, cover and surround, toilet bowl,

tank top and flushing system and waste tank and

outlet bowl.

An electrically powered flushing unit (three phase

115 Volt a.c. flush motor)

It collect waste material in the toilet waste tank

where it is disinfected, deodorized, dyed and the

liquids separated from the waste.

These liquids are then used for flushing purposes.


Typical Liquid Flush Toilet System




Liquid Flush Toilet Components

Malaysian Institute of Aviation Technology Liquid Flush Toilet Components


TOILET FLUSH MOTOR


• Motor drives both rotating filter and impeller to pump

Flushing Fluid to Flush Ring.

• Rotating filter consists of Stack of flat wheel shaped

discs apart determine the fines of filteration.

• A stationary knife blade is mounted beside the disc

stack and blade extending into the slot created by the

spacers.

• When rotate waste is combed through the slots by the

clean blades.

• Filter will break down the waste particles to 300

microns.

FLUSH MOTOR OPERATION






Flushing is initiated by pushing a button, energize

an electric timer runs a motor in the tank for 10

seconds cycle.

The pump impeller draws liquid through rotating

filter and pump through a flush ring around the top

of the toilet bowl with a swirling action.

This action carry the deposit into the waste tank by

opening the hinged separator.



It stop after 10 seconds, re-armed itself for next

cycle the motor will be reverse prevent rotating filter

becoming entangled with non-decomposable waste.

Electric toilet flush motors must be fitted with a

suitable thermal protection device (fuse or circuit

breaker) to prevent overheating due to failure of the

control circuit, control circuit components, the motor

or pump.

Some aircraft use compressed air to operate the

flush toilet.

LIQUID FLUSH TOILETS OPERATION


Vacuum/Compressed Air Flush

Toilet


Toilet

Servicing


Typical Toilet Waste Service Panel



Waste Line Bung



Toilet Waste Tank Ground Flush Line


TOILET SYSTEMS SERVICING

• With own external service panel situated on the lower

surface of the aircraft.

• If system with Waste Line Rubber is fitted must be

withdrawn using a “Y” COUPLING.

• A drain valve spring loaded to closed position be

opened by using a handle and emptied the waste via a

4 inches diameter pipe and coupling to toilet servicing

vehicle.

../PPS for PHOTO/TOILET SYSTEMS SERVICE PANEL.ppt


Toilet Drain Coupling


TOILET SYSTEMS SERVICING

After “Bung” is replaced in the drain pipe tank

is RINSED via the wash line and fill with

pre-charge of strong disinfectant chemical (Raquasan),

dye and deodorant and can be used till 100 times.


Leakage from this point can result in the formation of ice which might damage the aircraft.

Water spilled on the toilet floor is drained via a small diameter drain line, into the toilet waste tank drain line.

Waste drain fitting is heated electrically to prevent the freezing of any liquid in the drain line.

TOILET SYSTEMS SERVICE PANEL


Toilet Waste Service Panel


Toilet Waste Service Panel


Waste Line Bung


Vacuum Flush Toilet

Vacuum toilet bowl coated with silicon for non-stick effect


Vacuum Waste Tank

Malaysian Institute of Aviation Technology VACUUM TOILET SYSTEM


VACUUM SYSTEM TOILET

Liquid flush toilet create a risk of corrosion and it takes some time to drain and replenish each toilet.

Vacuum toilets overcome these problems by having dry toilet assemblies and is connected to a centralized storage tank by pipelines.



uses an evacuated waste container.

when toilet bowl is flushed, a valve opens and the waste is sucked along the pipeline into the storage tank then clean water from the drinking water tank is used to rinse the bowl and goes to the waste tank.



58

Malaysian Institute of Aviation Technology Typical Vacuum Toilet Schematic

Malaysian Institute of Aviation Technology TOILET FLUSH VALVE

Malaysian Institute of Aviation Technology VACUUM TOILET SYSTEM



OPERATION:

When the flush button is operated the cycle is started.

- If the aircraft is below 16,000 feet, the vacuum blowers are switched on.

- One second later, a water valve is opened and pumps 6 to 8 ounces of water to the rinse ring to clean the toilet bowl.


OPERATION:

When the flush button is operated the cycle is started.

- A flush valve opens for four seconds to allow the waste to be sucked into the waste tank.

- After the cycle is completed the vacuum blowers are switched off and the timer prepares for the next cycle.



Typical Vacuum Toilet Schematic


END OF TOILET SYSTEM


Cabin Interior System: Lavatory

Engineering