Boeing B777 - Air Systems

How does the trim air system meet zone temperature requirements?

It controls pack air temperature.

It cools or heats conditioned air.

It cools conditioned air.

It heats conditioned air.

Correct! Wrong!

Two outflow valves are installed: one forward and one aft. Normally, most of the outflow is through the forward outflow valve.

False.

True.

Correct! Wrong!

This improves ventilation and smoke removal. Cabin altitude and full ventilation rates can be maintained by either valve.

What action is required during preflight if the LANDING ALTITUDE EICAS message is displayed with the FWD and AFT OUTFLOW VALVE switches in AUTO?

Pull the LDG ALT

Push the LDG ALT selector IN.

Select the FWD and AFT OUTFLOW valve switches to MAN.

Push the LDG ALT selector OUT.

Correct! Wrong!

If a duct leak is detected, the system automatically isolates the leak. The EICAS caution message BLEED LEAK is displayed. The automatic isolation logic may include:

One or two sequential steps

Betwwen one and four sequential steps.

One, two, or three sequential steps.

Correct! Wrong!

During isolation, the ENGINE and/or APU bleed switch OFF lights and the ISOLATION switch CLOSED lights illuminate and extinguish as the repective valves close and open.

What will cause the automatic closure of a bleed valve?

Ground cart supplying bleed air.

APU operation

Bleed air overtemp or overpressure.

Engine fire switch pulled.

Correct! Wrong!

During climb, what parameter(s) schedule cabin altitude?

Airplane climb rate and flight plan cruise altitude.

Airplane flight altitude and pressure altitude.

A constant pressure differential.

Airplane flight altitude.

Correct! Wrong!

What determines the pack outlet temperature?

The flight deck temperature selector.

All statements are correct.

The CABIN TEMERATURE selector.

The temperature zone requiring the coolest temperature controls the pack outlet temperature.

Correct! Wrong!

Where is the target temperature for the air conditioning zones displayed?

On the HYD synoptic.

On the upper EICAS display when pressurization is selected to MAN.

On the air synoptic.

On the lower EICAS display when pressurization is selected to MAN.

Correct! Wrong!

Why should you minimize flight time at low altitude when the EQUIP COOLING OVRD message is displayed?

Pack temperature would cause damage.

Electronic Equipment and displays may fail.

Recirculation fans may not cool equipment adequately.

AFT and BULK cargo compartments may overheat.

Correct! Wrong!

Automatic ventilation of the Forward Cargo Compartment Air Conditioning System ensures that smoke and objectionable odors do not enter the flight deck or passenger cabin.

False.

True.

Correct! Wrong!

What happens when you select the FWR CARGO A/C control to AUTO?

The EICAS advisory message CARGO A/C FWD is displayed.

The forward cargo heating system is shutoff and a selected temperature is displayed on the AIR synoptic.

Packs operate at reduced flow rate.

Pack flow rate is modulated to achieve a pack outlet temperature between 5 and 43°C.

Correct! Wrong!

When is the center bleed isolation valve open?

During descent.

During engine start.

During climb and descent.

During single bleed source operation.

Correct! Wrong!

The aft and bulk cargo compartments have independent bleed air heating systems. An insulated curtain separates the two compartments.

False.

True.

Correct! Wrong!

Flight Deck Temperature (FLT DECK TEMP) selector in mid position sets the temperature to approximately 75°F (24°C)

True

False.

Correct! Wrong!

After engine start, what is the correct position for the L ENG and R ENG BLEED AIR switches?

AUTO.

ON.

OFF.

Correct! Wrong!

What protects the fuselage against excessive differential pressure?

Positive and negative pressure relief valves.

Recirculation fans.

Trim air valves

Cabin altitude limiter.

Correct! Wrong!

What is the cabin altitude at maximum certified airplane operating altitude?

7400 feet.

9000 feet.

8000 feet.

9400 feet.

Correct! Wrong!

Each trim air system supplies three zone supply ducts, with the left trim air system also supplying the flight deck.

True.

False.

Correct! Wrong!

Whic trim air valve can be moved directly by the flight crew, and how is it monitored?

Flight trim air valve - through a manual positions of the flight deck temperature selector.

Left trim air valve - monitored through the engine display.

Cabin trim air valve - monitored through the flight deck temperature selector.

Right trim air valve - monitored through the air synoptic.

Correct! Wrong!

Forward Equipment Cooling system does not reconfigure automatically to override mode automatically for which of the following?

When both supply fans fail in flight.

When the FWD CARGO FIRE ARM switch is ARMED.

When high air airflow is detected in flight.

When the EQUIP COOLING switch is in OVRD.

Correct! Wrong!

Which of the followings are bleed air sources?

APU and Ground Cart.

Packs.

Demand pump.

Trim air.

Correct! Wrong!

What must be done to manually set a landing altitude?

Adjust the trim air valves to the desired altitude.

Pull the manual landing elevation selector out then set the required altitude.

Press the AUTO button on the cabin altitude controller

Check the FMC for automatic landing elevation adjustment.

Correct! Wrong!

How many packs are there and what is their main function?

Four packs - controlling pressurization.

Two packs - cooling supplied hot bleed air.

Three packs - providing cooling.

One pack - managing ventilation.

Correct! Wrong!

Which of the following are landing elevation limits for B777?

2000 feet below to 13000 feet above sea level.

1000 feet below to 12000 feet above sea level.

1000 feet below to 14000 feet above sea level.

2000 feet below to 12000 feet above sea level.

Correct! Wrong!

What causes the trim air FAULT light to come on?

The trim air valve is commanded closed because of a zone supply duct overheat.

The trim air valve is commanded open

All statements are correct.

The pack flow control valves are commanded closed.

Correct! Wrong!

The LANDING ALTITUDE advisory message indicates which of the following?

The FMC does not supply a landing altitude or the landing altitude selector is pulled.

A landing was made to different altitude.

The preset landing altitude is not correct.

Correct! Wrong!

How are zone target temperatures selected, and what is the temperature range?

Manually set by the cabin crew with a temperature range between 0°C and 30°C.

Manually set by the flight crew with a temperature range between 18°C and 29°C.

Automatically adjusted based on the outside temperature with a temperature range between 15°C and 35°C.

Automatically set by the system with a temperature range between 10°C and 40°C.

Correct! Wrong!

During preflight, what position should the FWD and AFT OUTFLOW VALVE switches and LDG ALT selector be in?

OUTFLOW VALVE switches in MAN and LDG ALT selector pushed IN.

OUTFLOW VALVE switches in AUTO and LDG ALT selector pushed IN.

OUTFLOW VALVE switches in AUTO and LDG ALT selector pulled out.

OUTFLOW VALVE switches in OFF and LDG ALT selector pushed IN.

Correct! Wrong!

Why should the CABIN TEMP control be set to mid position?

To set the maximum temperature in any zone.

To prevent cabin overheat during low altitude flight

To set the actual temperature in cabin zones A-F.

To allows ± 6˚C temperature range adjustment on cabin attendant panel.

Correct! Wrong!

What cabin differential pressure is scheduled for takeoff?

Equal to the outside pressure.

Slighlty positive.

Slighlty negative.

Zero.

Correct! Wrong!

What landing altitude is displayed on the EICAS pressurization system indications when the airplane has traveled more than 400 miles or has passed the halfway point?

The destination airport altitude to the nearest 100 feet.

The destination airport altitude to the nearest 500 feet.

The departure airport altitude to the nearest 100 feet.

The alternate airport altitude to the nearest 50 feet.

Correct! Wrong!

What system provides the heat for the forward cargo compartment?

The trim air system.

Bleed air from the engines.

Aft cargo heat system.

Exhaust from the equipment cooling system.

Correct! Wrong!

If the cruise altitude is unavailable from the FMC in AUTO, the cabin altitude controllers assume a cruise altitude of 39,000 feet.

True.

False.

Correct! Wrong!

What is the indication that an outflow valve is in manual control?

Amber 'M' on the outflow valve indications.

No indication. Manual control is not displayed.

Green light on the outflow valve.

Red light on the air synoptic.

Correct! Wrong!

In flight, the cabin altitude controller operates in:

A cruise mode.

A climb mode.

A descent mode.

All statements are correct.

Correct! Wrong!

Which system(s) supply trim air to the flight deck?

Center trim air system.

Left trim air system.

Both right and left trim air systems.

Right trim air system.

Correct! Wrong!

Where does air to the cabin come from, and what are the additional sources?

Left pack - upper recirculation system.

Right pack - lower recirculation system.

APU bleed air - outflow valves.

Both packs - upper and lower recirculation systems.

Correct! Wrong!

What happens if the FLT DECK TEMP control is moved to the 'C' position?

It opens the flight deck trim air valve.

It closes the trim air valve and lowers the flight deck temperature.

The pack temperature decreases.

It cancels input to the flight deck temperature controller.

Correct! Wrong!

What is the function of the negative pressure relief vents?

They prevent negative pressure differential.

They improve smoke removal ventilation.

They minimize cabin overpressure conditions.

They regulate cabin pressure during climb.

Correct! Wrong!

What does the PACK MODE R EICAS message indicate?

The standby cooling mode is inoperative

The right pack is inoperative.

The airplane is in unfavorable conditions and right pack output temperature is too high.

The right pack is operating in the standby cooling mode.

Correct! Wrong!

What is the normal source of bleed air to start the second engine?

APU.

Engine.

Ground cart(s)

Correct! Wrong!

During normal bleed air operation, what position should the L, C, R ISLN BLEED AIR switches be in?

L ISLN AUTO, R ISLN AUTO, C ISLN OFF.

ON.

AUTO.

OFF.

Correct! Wrong!

Which component can be reset by the air conditioning reset switch.

Trim air valves and recirculation fans.

Packs only.

Reciculation fan switches only.

The entire air conditioning system.

Correct! Wrong!

In the standby cooling mode, what will the pack automatically do if the airplane is not in an area of sufficient cooling?

Decrease airflow to half rate.

Fail the pack standby cooling controller.

Increase airflow through the pack.

Shutoff the pack.

Correct! Wrong!

When does a visible orange lip indicate on a pressure relief valve?

Advise maintenance of the open valve.

Position the landing altitude switch to AUTO.

Set cabin altitude to less than 8000 ft.

No action is required. The valve is in its normally closed position.

Correct! Wrong!

In flight, the normal source of bleed air for all systems except the engine anti-ice is the engine low stage compressor (at high power) or intermediate stage compressor (at low power).

True.

False.

Correct! Wrong!

What is the normal position of the forward outflow valve after landing?

In transit.

Full open.

Full closed.

30 degrees open.

Correct! Wrong!

What happens when the BULK CARGO TEMPERATURE selector is positioned to HIGH?

The bulk cargo compartment ventilation fan operates continuously.

The compartment temperature is automatically kept at approximately 15°C.

The compartment temperature is automatically kept at approximately 21°C.

The compartment temp. İs automatically kept approximately 7°C.

Correct! Wrong!

With the CARGO TEMPERATURE selector set to LOW or HIGH, the respective cargo heat shutoff valve opens and the temperature control valve opens and closes to maintain the temperature in the compartment.

The lavatory/galley vent fans draw air across temperature sensors in each compartment. If both vent fans fail, cargo heat is not provided.

The lavatory/galley vent fans draw air across temperature sensors in each compartment.

The lavatory vent fans draw air across temperature sensors in each compartment. If both vent fans fail, cargo heat is still provided but at a low rate.

Correct! Wrong!

During preflight, what position should the APU BLEED AIR switch be in?

AUTO or OFF

OFF.

AUTO.

Correct! Wrong!

In the cabin altitude controller cruise mode, maximum cabin altitude is 8,000 feet. The cabin altitude controllers enter cabin altitude controller descent mode at T/D or at initial descent of approximately _____ from cruise altitude, regardless of T/D.

750 ft.

1000 ft.

1500 ft.

500 ft.

Correct! Wrong!

For Boeing 777, the APU Bleed Air is available at all altitudes.

False.

True.

Correct! Wrong!

When is the pack OFF light illuminated amber?

All statements are true.

During engine start.

When there is a pack or compressor outlet high temperature condition.

When the valve ıs failed closed.

Correct! Wrong!

If an overheat or other significant pack fault is detected, the pack shuts down automatically. An attempt to restore pack operation may not be made by pressing the AIR COND RESET switch.

False.

True.

Correct! Wrong!

If one pack is in standby cooling and the other pack is operating normally, the pack in standby cooling mode shuts down at lower altitudes and higher outside air temperatures when ambient conditions do not permit standby cooling.

False.

True.

Correct! Wrong!

Which of the following is false for the PACK Switch illuminating OFF?

The pack valve is failed or closed.

A pack or compressor outlet high temperature has occurred.

Bleed air pressure is inadequate.

The PACK switched is pushed on.

Correct! Wrong!

What does the MAN position on the FLT DECK TEMP control do?

It causes the packs to provide air at an average mid temperature range.

It removes control at the cabin attendant panel.

It removes power from the trim air system.

It allows the trim air valve to operate manually.

Correct! Wrong!

What is the source of supplemental heat for the aft cargo compartment?

Forward equipment cooling exhaust air.

An electric heater.

Left recirculation fan.

An independent bleed air heating system.

Correct! Wrong!

What is the most correct statement about the equipment cooling override mode?

The mode is selected automatically, the EICAS message EQUIP COOLING OVRD is displayed. There is a non normal procedure for this message.

The mode is selected automatically.

The mode is selected automatically, and the EICAS message EQUIP COOLING OVRD is displayed.

The EICAS message EQUIP COOLING OVRD is displayed and there is a non normal procedure to be performed.

Correct! Wrong!

How are cargo compartments controlled in terms of temperature ranges?

Low is 10°C to 15°C - High is 25°C to 30°C

Low is 0°C to 5°C - High is 15°C to 24°C

Low is 4°C to 10°C - High is 18°C to 24°C

Low is 5°C to 10°C - High is 20°C to 25°C

Correct! Wrong!

If a pack overheats or fails the pack shuts down and an air conditioning may be needed.

True.

False.

Correct! Wrong!

If landing altitude is unavailable from the FMC (and not set in MAN), the EICAS advisory message LANDING ALT is displayed. The cabin altitude controller:

Assumes a landing altitude of 1000 ft.

Assumes a landing altitude of 200 ft.

Assumes a landing altitude of 2000 ft.

Assumes a landing altitude of 1500 ft.

Correct! Wrong!

Landing altitude (normally provided by the FMC) can be manually set using the LANDING ALTITUDE selector. Landing field selection limits are _ below sea level to _ feet above sea level.

1000 ft and 13 000 ft

2000 ft and 14 000 ft.

1500 ft and 16 000 ft.

1000 ft and 15 000 ft.

Correct! Wrong!

If cruise altitude is unavailable from the FMC in AUTO, the cabin altitude controllers assume a cruise altitude of:

35 000 ft.

37 000 ft.

39 000 ft.

33 000 ft.

Correct! Wrong!

The controller uses ambient pressure and flight plan data from the FMC to calculate a cabin pressurization schedule. The schedule provides a comfortable cabin climb to cruise altitude.

True.

False.

Correct! Wrong!

Why does the flight deck receive air from the left pack at a higher pressure than the passenger cabin?

To defog the forward windows.

To prevent smoke from entering the flight deck.

To cool the equipment in the aisle stand.

Correct! Wrong!

The cabin altitude limiter closes both outflow valves if cabin altitude exceeds:

10 000 ft.

15 000 ft.

14 000 ft.

13 500 ft

Correct! Wrong!

Why should you minimize flight time at low altitude when the EQUIP COOLING OVRD message is displayed?

Equipment and displays could fail.

Recirculation fans may not cool equipment adequately.

AFT and BULK cargo compartments may overheat.

Pack temperature would cause damage.

Correct! Wrong!

What happens if the forward equipment cooling primary supply fan fails?

The EICAS advisory message EQUIP COOLING is displayed.

The aft equipment cooling and ventilating system provides cooling.

The forward system reconfigures automatically to an override mode.

The backup supply fan operates automatically.

Correct! Wrong!

When does the ground crew call horn sound?

When cooling of forward electronic electrical equipment is inoperative.

Before starting the engine.

When hydraulics systems are pressurized.

In case of APU fire.

Correct! Wrong!

What is bleed air used for?

Aspirating the TAT probe.

Pressurizing the hydraulics reservoir.

Pressurizing the hydraulics reservoir and sspirating the TAT probe.

Correct! Wrong!

Boeing B777 – Air Systems

Quiz

Boeing B777 - Air Systems

How does the trim air system meet zone temperature requirements?

Two outflow valves are installed: one forward and one aft. Normally, most of the outflow is through the forward outflow valve.

What action is required during preflight if the LANDING ALTITUDE EICAS message is displayed with the FWD and AFT OUTFLOW VALVE switches in AUTO?

If a duct leak is detected, the system automatically isolates the leak. The EICAS caution message BLEED LEAK is displayed. The automatic isolation logic may include:

What will cause the automatic closure of a bleed valve?

During climb, what parameter(s) schedule cabin altitude?

What determines the pack outlet temperature?

Where is the target temperature for the air conditioning zones displayed?

Why should you minimize flight time at low altitude when the EQUIP COOLING OVRD message is displayed?

Automatic ventilation of the Forward Cargo Compartment Air Conditioning System ensures that smoke and objectionable odors do not enter the flight deck or passenger cabin.

What happens when you select the FWR CARGO A/C control to AUTO?

When is the center bleed isolation valve open?

The aft and bulk cargo compartments have independent bleed air heating systems. An insulated curtain separates the two compartments.

Flight Deck Temperature (FLT DECK TEMP) selector in mid position sets the temperature to approximately 75°F (24°C)

After engine start, what is the correct position for the L ENG and R ENG BLEED AIR switches?

What protects the fuselage against excessive differential pressure?

What is the cabin altitude at maximum certified airplane operating altitude?

Each trim air system supplies three zone supply ducts, with the left trim air system also supplying the flight deck.

Whic trim air valve can be moved directly by the flight crew, and how is it monitored?

Forward Equipment Cooling system does not reconfigure automatically to override mode automatically for which of the following?

Which of the followings are bleed air sources?

What must be done to manually set a landing altitude?

How many packs are there and what is their main function?

Which of the following are landing elevation limits for B777?

What causes the trim air FAULT light to come on?

The LANDING ALTITUDE advisory message indicates which of the following?

How are zone target temperatures selected, and what is the temperature range?

During preflight, what position should the FWD and AFT OUTFLOW VALVE switches and LDG ALT selector be in?

Why should the CABIN TEMP control be set to mid position?

What cabin differential pressure is scheduled for takeoff?

What landing altitude is displayed on the EICAS pressurization system indications when the airplane has traveled more than 400 miles or has passed the halfway point?

What system provides the heat for the forward cargo compartment?

If the cruise altitude is unavailable from the FMC in AUTO, the cabin altitude controllers assume a cruise altitude of 39,000 feet.

What is the indication that an outflow valve is in manual control?

In flight, the cabin altitude controller operates in:

Which system(s) supply trim air to the flight deck?

Where does air to the cabin come from, and what are the additional sources?

What happens if the FLT DECK TEMP control is moved to the 'C' position?

What is the function of the negative pressure relief vents?

What does the PACK MODE R EICAS message indicate?

What is the normal source of bleed air to start the second engine?

During normal bleed air operation, what position should the L, C, R ISLN BLEED AIR switches be in?

Which component can be reset by the air conditioning reset switch.

In the standby cooling mode, what will the pack automatically do if the airplane is not in an area of sufficient cooling?

When does a visible orange lip indicate on a pressure relief valve?

In flight, the normal source of bleed air for all systems except the engine anti-ice is the engine low stage compressor (at high power) or intermediate stage compressor (at low power).

What is the normal position of the forward outflow valve after landing?

What happens when the BULK CARGO TEMPERATURE selector is positioned to HIGH?

With the CARGO TEMPERATURE selector set to LOW or HIGH, the respective cargo heat shutoff valve opens and the temperature control valve opens and closes to maintain the temperature in the compartment.

During preflight, what position should the APU BLEED AIR switch be in?

In the cabin altitude controller cruise mode, maximum cabin altitude is 8,000 feet. The cabin altitude controllers enter cabin altitude controller descent mode at T/D or at initial descent of approximately _____ from cruise altitude, regardless of T/D.

For Boeing 777, the APU Bleed Air is available at all altitudes.

When is the pack OFF light illuminated amber?

If an overheat or other significant pack fault is detected, the pack shuts down automatically. An attempt to restore pack operation may not be made by pressing the AIR COND RESET switch.

If one pack is in standby cooling and the other pack is operating normally, the pack in standby cooling mode shuts down at lower altitudes and higher outside air temperatures when ambient conditions do not permit standby cooling.

Which of the following is false for the PACK Switch illuminating OFF?

What does the MAN position on the FLT DECK TEMP control do?

What is the source of supplemental heat for the aft cargo compartment?

What is the most correct statement about the equipment cooling override mode?

How are cargo compartments controlled in terms of temperature ranges?

If a pack overheats or fails the pack shuts down and an air conditioning may be needed.

If landing altitude is unavailable from the FMC (and not set in MAN), the EICAS advisory message LANDING ALT is displayed. The cabin altitude controller:

Landing altitude (normally provided by the FMC) can be manually set using the LANDING ALTITUDE selector. Landing field selection limits are _____ below sea level to _____ feet above sea level.

If cruise altitude is unavailable from the FMC in AUTO, the cabin altitude controllers assume a cruise altitude of:

The controller uses ambient pressure and flight plan data from the FMC to calculate a cabin pressurization schedule. The schedule provides a comfortable cabin climb to cruise altitude.

Why does the flight deck receive air from the left pack at a higher pressure than the passenger cabin?

The cabin altitude limiter closes both outflow valves if cabin altitude exceeds:

Why should you minimize flight time at low altitude when the EQUIP COOLING OVRD message is displayed?

What happens if the forward equipment cooling primary supply fan fails?

When does the ground crew call horn sound?

What is bleed air used for?

Landing altitude (normally provided by the FMC) can be manually set using the LANDING ALTITUDE selector. Landing field selection limits are _ below sea level to _ feet above sea level.