ATR 72 - Pressurization

What is the meaning of this display?

Manual pressure control nominal display.

Invalid CAB ALT.

Manual pressure control invalid target.

Correct! Wrong!

An invalid display can be due to sensors failure (out of range measurement) or a missing connection.

TEST pb - When pressed, the system is electrically tested. If the system is ready to use, the LANDING ELEVATION indicator displays alternately 18800 and -8800.

FAULT light comes on amber on CAB PRESS MODE SEL pb and a white PRESS TEST indication is visible on EWD.

FAULT light comes on blue on CAB PRESS MODE SEL pb.

FAULT light comes on amber on CAB PRESS MODE SEL pb.

Correct! Wrong!

In flight, this test is inhibited.

What is the correct way to switch from manual to automatic operation?

Select to AUTO MODE the CABIN PRESS pb and turn the MAN RATE KNOB smoothly to the normal position.

Select to AUTO MODE the CABIN PRESS pb.

Turn the MAIN RATE KNOB to the normal position and select to AUTO MODE the CABIN PRESS pb.

Correct! Wrong!

The digital controller is supplied by the:

DC EMER BUS.

DC BUS 1.

DC BUS 2.

Correct! Wrong!

An overpressure relief valve and a negative pressure relief valve are fitted on both outflow valves as safety devices.

True.

False.

Correct! Wrong!

LANDING ELEVATION indicator - Displays in ft the landing elevation setting. The two last digits always display 0. All digits turn off in case of:

Automatic system failure, manual mode or DUMP mode.

Automatic system failure, or invalid data.

Automatic system failure, invalid data or DUMP mode.

Correct! Wrong!

ELV SET trigger switch - Enables selection of the elevation of the planned destination airport in 100 ft increments. The landing altitude ranges between:

- 1500 ft and 10000 ft.

- 300 ft and 12000 ft.

- 750 ft and 13000 ft.

Correct! Wrong!

Maximum differential pressure is:

6.75 psi.

6.35 psi

6.55 psi

Correct! Wrong!

How is the system protected against exceeding the maximum cabin differential pressure?

Only the electropneumatic valve incorporates a manometric capsule to hold the valve open sufficiently to prevent overpressure.

Both outflow valves incorporate an electrically driven torque motor designed to fully open the valve.

Both outflow valves incorporate a namometric capsule (aneroid) to hold the valve open sufficiently to prevent overpressure.

Correct! Wrong!

A DUMP function is available to send a fully open electrical signal to the electropneumatic outflow valve. DUMP function is available with the pressurization system in:

AUTO mode.

AUTO mode when differential pressure is below 1 psi.

AUTO mode when differential pressure is below 2.8 psi.

Correct! Wrong!

When the DUMP guarded pb is pressed while in AUTO mode, the FAULT light of the MAN PRESS CONTROL panel comes on amber.

True.

False.

Correct! Wrong!

Four electrical motors (two for each outflow valves) maintain both outflow valves in closed position.

True.

False.

Correct! Wrong!

There are two electrical motors (one for each outflow valves) that maintain both outflow valves in closed position.

A DUMP function is available to send a fully open electrical signal to the electropneumatic outflow valve. DUMP function is available with the pressurization system in AUTO or MAN mode.

False.

True.

Correct! Wrong!

DUMP function is available as long as pressurization system is in AUTO mode.

Manual pressurization mode - The electropneumatic outflow valve is maintained closed and the pneumatic outflow valve controls the cabin outlet air flow. Its control servo pressure is function of the manual controller demand. The control knob is used to select any cabin rate of change from:

-2 500 ft/min to +2 500 ft/min.

-1 300 ft/min to +2 000 ft/min.

-1 500 ft/min to +2 500 ft/min.

Correct! Wrong!

DESCENT RATE pb - When the FAST pb is pressed in, the max cabin vertical speed in descent is:

-500 ft/min.

-650 ft/min.

- 900 ft/min

Correct! Wrong!

The FAST LIGHT comes on cyan.

When the pressurization system is operating in the AUTO-mode, the pneumatic outflow valve is slaved to the electropneumatic valve.

False.

True.

Correct! Wrong!

Maximum altitude for one bleed off operation is:

15 000 ft.

18 000 ft.

20 000 ft.

Correct! Wrong!

ATR 72 – Pressurization

Quiz

ATR 72 - Pressurization

What is the meaning of this display?

TEST pb - When pressed, the system is electrically tested. If the system is ready to use, the LANDING ELEVATION indicator displays alternately 18800 and -8800.

What is the correct way to switch from manual to automatic operation?

The digital controller is supplied by the:

An overpressure relief valve and a negative pressure relief valve are fitted on both outflow valves as safety devices.

LANDING ELEVATION indicator - Displays in ft the landing elevation setting. The two last digits always display 0. All digits turn off in case of:

ELV SET trigger switch - Enables selection of the elevation of the planned destination airport in 100 ft increments. The landing altitude ranges between:

Maximum differential pressure is:

How is the system protected against exceeding the maximum cabin differential pressure?

A DUMP function is available to send a fully open electrical signal to the electropneumatic outflow valve. DUMP function is available with the pressurization system in:

When the DUMP guarded pb is pressed while in AUTO mode, the FAULT light of the MAN PRESS CONTROL panel comes on amber.

Four electrical motors (two for each outflow valves) maintain both outflow valves in closed position.

A DUMP function is available to send a fully open electrical signal to the electropneumatic outflow valve. DUMP function is available with the pressurization system in AUTO or MAN mode.

Manual pressurization mode - The electropneumatic outflow valve is maintained closed and the pneumatic outflow valve controls the cabin outlet air flow. Its control servo pressure is function of the manual controller demand. The control knob is used to select any cabin rate of change from:

DESCENT RATE pb - When the FAST pb is pressed in, the max cabin vertical speed in descent is:

When the pressurization system is operating in the AUTO-mode, the pneumatic outflow valve is slaved to the electropneumatic valve.

Maximum altitude for one bleed off operation is: