# B777 Balance And Servicing

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Quizzes Created: 10 | Total Attempts: 6,771
Questions: 16 | Attempts: 256

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• 1.

### What is the minimum duct pressure for starting when performing a crossbleed start?

• A.

15 PSI

• B.

25 PSI

• C.

45 PSI

• D.

55 PSI

B. 25 PSI
Explanation
The minimum duct pressure required for starting when performing a crossbleed start is 25 PSI. This means that the air pressure in the duct must be at least 25 PSI in order to successfully initiate the start process.

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• 2.

### When can the ground handling bus be powered?

• A.

On the ground, with either APU or external power available.

• B.

Only when the APU is running while on the ground

• C.

Either on the ground or in flight, with APU power available.

• D.

On the ground, with the ground service switch selected.

A. On the ground, with either APU or external power available.
Explanation
The ground handling bus can be powered when the aircraft is on the ground and either the APU (Auxiliary Power Unit) or external power is available. This means that the bus can be powered by either the onboard APU or by an external power source connected to the aircraft. It is important to have the ground handling bus powered during ground operations to provide electrical power for various equipment and systems, such as loading and unloading cargo, servicing the aircraft, and other ground handling operations.

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• 3.

### Which statement is true regarding fuel crossfeed?

• A.

Crossfeed valves are normally open, providing fuel feed from tank to engine.

• B.

Although there are two valves, only open crosfeed valve is required for successful crossfeed operatrion.

• C.

There is only one crossfeed valve even though there are two switches to control it.

• D.

Fuel crossfeed can only be accomplished in the air.

B. Although there are two valves, only open crosfeed valve is required for successful crossfeed operatrion.
Explanation
Fuel crossfeed is a process in which fuel is transferred from one tank to another during flight. In this case, the correct answer states that although there are two valves, only the open crossfeed valve is required for successful crossfeed operation. This means that if one of the valves is closed or not functioning, the crossfeed operation can still be achieved as long as the open valve is functioning properly. This information suggests that both valves do not need to be open simultaneously for fuel crossfeed to occur.

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• 4.

### What indicates that a hydraulic reservoir needs refilling?

• A.

EICAS message REFILL HYD RES

• B.

Hydraulic quantity displayed less than .75 on the status display

• C.

A white RF next to the hydraulic quantity on the status display

• D.

Hydraulic quantity displayed less than .75 the CDU.

C. A white RF next to the hydraulic quantity on the status display
Explanation
A white RF next to the hydraulic quantity on the status display indicates that the hydraulic reservoir needs refilling.

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• 5.

### What braking power is available with brake accumulator pressure as the only source of braking?

• A.

Twelve or more full brake applications

• B.

Several braking applications or parking brake applications

• C.

Fully charged,3000 PSI available

• D.

Greater than 1475 PSI available

B. Several braking applications or parking brake applications
Explanation
The correct answer is "Several braking applications or parking brake applications". This means that the brake accumulator pressure can provide enough braking power for multiple instances of braking or for engaging the parking brake.

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• 6.

### When connecting a Ground Air Conditioning Cart, what action is required in order to allow the cart to operate at maximum efficiency?

• A.

Pack Control Selectors………………MAN

• B.

Pack Control Selectors………………AUTO

• C.

Recirculation Fans Switches…………ON

• D.

Recruitment Fans Switches…………OFF

D. Recruitment Fans Switches…………OFF
Explanation
To allow the ground air conditioning cart to operate at maximum efficiency, the recruitment fans switches need to be turned off. This is because the recruitment fans are used to bring in outside air into the aircraft, which can decrease the efficiency of the air conditioning system. By turning off the recruitment fans, the cart can focus solely on providing cool air to the aircraft without the need to constantly bring in outside air.

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• 7.

### After application of de-icing fluids to the exterior of the airplane, how long should you wait before restoring normal Engine and APU bleed air operation?

• A.

Approximately 1 minute

• B.

3 minutes

• C.

5 minutes

• D.

None, normal bleed air operation is allowed during de-icing procedures.

A. Approximately 1 minute
Explanation
After the application of de-icing fluids to the exterior of the airplane, it is recommended to wait for approximately 1 minute before restoring normal Engine and APU bleed air operation. This waiting period allows the de-icing fluids to properly remove any ice or frost buildup on the aircraft's surfaces. Restoring normal bleed air operation too soon may result in the fluids not being effective in removing all the ice or frost, which could potentially affect the aircraft's performance and safety.

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• 8.

### At what fuel quantity would the fuel imbalance pointer be displayed?

• A.

Main tank fuel differs more than 1000 pounds (500 kg).

• B.

Main tank fuel offers by more than 200 pounds (100 kg) and the crossfeed valve is open

• C.

Fuel difference between any tank is greater than 1000 pounds (500kg)

• D.

Main tank fuel differs more than 1000 pounds (500 kg) or the main tank fuel differs more than 200 pounds (100kg) and a crossfeed valve is open.

D. Main tank fuel differs more than 1000 pounds (500 kg) or the main tank fuel differs more than 200 pounds (100kg) and a crossfeed valve is open.
Explanation
The fuel imbalance pointer would be displayed when the main tank fuel differs more than 1000 pounds (500 kg) or when the main tank fuel differs more than 200 pounds (100 kg) and a crossfeed valve is open. This means that if there is a significant difference in fuel quantity between the main tanks or if there is a smaller difference but the crossfeed valve is open, the fuel imbalance pointer will be displayed to indicate the fuel imbalance.

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• 9.

### With a combination of light gross weight and aft CG, what considerations should the pilot take to improve take-off controllability?

• A.

None. The airplane automatically compensates

• B.

Use reduced thrust combined with a rolling takeoff

• C.

Use maximum take-off thrust

• D.

Use 1 additional unit of nose down trim

B. Use reduced thrust combined with a rolling takeoff
Explanation
When the aircraft has a light gross weight and an aft center of gravity (CG), it can result in reduced controllability during takeoff. To improve the controllability, the pilot should use reduced thrust combined with a rolling takeoff. This means using less power during the takeoff and initiating the rotation smoothly to prevent any sudden pitch changes. This technique helps in maintaining better control over the aircraft during the critical phase of takeoff, ensuring a safer and more stable departure.

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• 10.

### Take of stabilizer trim setting is computed by the FMC using which of the following?

• A.

Only the airplane gross weight

• B.

CG and runway length

• C.

CG, gross weight, and take-off thrust

• D.

CG and takeoff thrust

C. CG, gross weight, and take-off thrust
Explanation
The FMC (Flight Management Computer) computes the takeoff stabilizer trim setting using the aircraft's center of gravity (CG), gross weight, and takeoff thrust. These factors are crucial in determining the appropriate trim setting for a safe and balanced takeoff. The CG affects the aircraft's stability and balance, while the gross weight and takeoff thrust impact the aircraft's performance during takeoff. By considering all three factors, the FMC ensures that the stabilizer trim setting is optimized for a successful takeoff.

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• 11.

### What indicates that the engine oil quality is low?

• A.

Oil quantity less than 19 quarts (15 liters)

• B.

EICAS message OIL QUANTITY LOW

• C.

A magenta LO indication on the Status page

• D.

A white LO indication on the secondary engine display

D. A white LO indication on the secondary engine display
Explanation
A white LO indication on the secondary engine display indicates that the engine oil quality is low.

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• 12.

### What is the first step to take when a fuel imbalance exist between the right and left main tasks and fuel balancing is required?

• A.

Fuel pump switches (low tank)……Off

• B.

Crossfeed switches (either)………On

• C.

Crossfeed switches (either)………..Off

• D.

Fuel pump switches (low tank)…….On

B. Crossfeed switches (either)………On
Explanation
When a fuel imbalance exists between the right and left main tanks and fuel balancing is required, the first step to take is to turn on the crossfeed switches. This allows fuel to be transferred between the tanks, helping to equalize the fuel levels.

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• 13.

### What does the FMS CDU message FUEL DISAGREE-PROG 2/3 indicate?

• A.

The predicate fuel at destination is less than the FMC pilot entered reserves.

• B.

The fuel quantity is low in either main tank.

• C.

There is a fuel imbalance between the main tanks.

• D.

The totalizer fuel quantity and the FMC calculated disagree by 9000 pounds (4080 kilograms) for more than 5 minutes.

D. The totalizer fuel quantity and the FMC calculated disagree by 9000 pounds (4080 kilograms) for more than 5 minutes.
Explanation
The FMS CDU message "FUEL DISAGREE-PROG 2/3" indicates that there is a disagreement between the totalizer fuel quantity and the FMC calculated fuel quantity. This disagreement is by 9000 pounds (4080 kilograms) and has been ongoing for more than 5 minutes.

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• 14.

### What are the fuel tank capacities?

• A.

Each main tank contains 62,300 pounds and the center tank contains 83,100 pounds.

• B.

Each main tank contains 83,100 pounds and the center tank contains 62,300 pounds.

• C.

Each main tank contains 64,100 pounds and the center tank contains 174,900 pounds.

• D.

Each main tank contains 69,000 pounds and the center tank contains 182,000 pounds.

C. Each main tank contains 64,100 pounds and the center tank contains 174,900 pounds.
• 15.

### What are the fuel tank capacities?

• A.

Each main tank contains 28,300 kilograms and the center tank contains 37,700 kilograms.

• B.

Each main tank contains 37,700 kilograms and the center tank contains 28,300 kilograms.

• C.

Each main tank contains 29,100 kilograms and the center tank contains 79,300 kilograms.

• D.

Each main tank contains 31,300 kilograms and the center tank contains 145,500 kilograms.

D. Each main tank contains 31,300 kilograms and the center tank contains 145,500 kilograms.
Explanation
The given answer is correct because it states that each main tank contains 31,300 kilograms, which is different from the other options. Additionally, it states that the center tank contains 145,500 kilograms, which is also different from the other options. Therefore, this answer provides the accurate fuel tank capacities as specified in the question.

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• 16.

### When does the EICAS message APU LIMIT display?

• A.

When the APU has increased EGT

• B.

When the APU has increased oil temperature or reduced oil pressure

• C.

When APU operation has exceeded a limit

• D.

When the APU has automatically shut down for exceeding a limit