11.17 Water And Waste

Question 1

What are the 3 water subsystems?

Answer 1

• Potable water
• waste water
• toilet waste systems

Question 2

What does the potable water system supply? [2]

Answer 2

• Toilets

- galleys

Question 3

What are the potable water tanks made out of?

Answer 3

Glass fibre reinforced plastic

Question 4

Where are the portable water tanks located?

Answer 4

Pressurised under floor area of the fuselage

Question 5

What does a mixer valve do in the lavatory water system?

Answer 5

Mixes a supply of cold water from the header and hot water from the water heater

Question 6

What types of faucets are there? [2]

Answer 6

• Mechanical

- infrared faucets

Question 7

What components can be found in a lavatory water system? [5]

Answer 7

• Header to distribute water
• Manual shut off valve
• Water heater
• Mixer valve
• Washbasin with faucets

Question 8

How is the infrared faucet controlled?

Answer 8

By reflective sensor units with 2 lenses,

The reflective sensor opens a solenoid operated shut off valve on the mixer unit

Question 9

How much water can a water heater hold?

Answer 9

Approx 3 pints

Question 10

What components can be found on the water heater? [4]

Answer 10

• Manual on/off switch,
• Indicating light,
• Pressure relief valve
• Over heat switch

Question 11

At what temperature will the overheat switch open in the water heater?

Answer 11

90 degree c

Question 12

At what pressure does the pressure relief valve open on the water heater?

Answer 12

140 psi

Question 13

What is used to pressurise the potable water system? [2]

Answer 13

• Bleed air from pneumatics

- or electrical air compressor when pneumatics unavailable

Question 14

At what psi will the pressure switch close to activate the electrical air compressor?

Answer 14

30 psi

Question 15

Where can the water service panel be found?

Answer 15

Lower part of the fuselage in a recess

Question 16

What are the main components of the water service panel? (4)

Answer 16

• T-handle
• a fill fitting with protective cap
• water quantity indicator
• air compressor interlock switch

Question 17

What is quantity detection controlled by?

Answer 17

Quantity control unit

Question 18

Where Is the waste from the toilet collected?

Answer 18

In waste tanks

Question 19

Where does the waste water from the galleys and washbasins go?

Answer 19

Out of the aircraft through drain lines and drain masts

Question 20

What two types of toilet waste systems are there?

Answer 20

• Vacuum

- Flush motor toilets

Question 21

What are the main components for a flush motor toilet? [4]

Answer 21

• Flushing equipment with flush handle
• Flush motor assembly
• Waste tank
• Drain equipment

Question 22

What is found in the flush motor assembly?

Answer 22

Impeller pump

Question 23

What does the impeller pump do?

Answer 23

Pumps liquid from the tank through filter basket to spray on the toilet bowl

Question 24

What powers the flush motor?

Answer 24

3 phase electric motor

Question 25

What is positioned on the flush motor assembly to prevent clogging of the filter?

Answer 25

A wiper blade

Question 26

How many times can the flush motor toilet be used for?

Answer 26

Approx 100 times

Question 27

What is the valve called that prevents back flow of water from the toilet to the potable water system?

Answer 27

Anti siphon valve

Question 28

How is the waste transported from the toilet to the waste tank?

Answer 28

By differential pressure generated by the vacuum system

Question 29

What does the waste tank have to indicate waste levels

Answer 29

Level sensor

Question 30

On the water panel, what will you find? [2]

Answer 30

• Drain fitting

- drain valve handles for each individual tank

Question 31

What does the safety valve do on the water panel?

Answer 31

Prevents leakage of waste from a fault drain valve

Question 32

How would you drain a waste tank?

Answer 32

• Attach the line from the service cart,
• open the safety valve,
• Pull the drain valve handle opening the drain valve

Question 33

What must you Do when you have drained a tank?

Answer 33

Flush it with clean water