Aircraft Fuel Systems

Question 1

Fuel jettisoning is usually accomplished

Answer 1

through a common manifold and outlet in each wing

Question 2

The primary purpose of aircraft fuel jettison system is to quickly achieve a

Answer 2

lower landing weight

Question 3

Fuel jettison valve must be designed to allow flight personnel

Answer 3

to close the valve at any time and the fuel must discharge clear of the aircraft

Question 4

Which of the following is employed to maintain lateral stability when jettisoning fuel?

Answer 4

Two separate independent systems

Question 5

A fuel jettison system is required under certain conditions if the maximum takeoff weight exceeds the maximum landing weight. What regulation covers the requirements of fuel jettison?

Answer 5

(FAR) 14 CFR 23, 25 and CAM 4b

Question 6

Fuel is moved overboard in most fuel jettison systems by

Answer 6

boost pumps

Question 7

Fuel jettisoning past the limits prescribed by Federal Aviation Regulations is usually prevented by

Answer 7

dump limit valves or a low-level circuit

Question 8

Which procedure must be followed when defuelling aircraft with sweptback wings?

Answer 8

Defuel outboard wing tanks first

Question 9

Normal fuel crossfeed system operation in multi-engine aircraft

Answer 9

provides a means to maintain a balanced fuel load condition

Question 10

How many vents, arranged so that they are not likely to become plugged at the same time, must be used in multi engine fuel systems?

Answer 10

Two

Question 11

What is the primary purpose of the cross-feed system?

Answer 11

It allows any tank to supply fuel to any engine

Question 12

Fuel system components must be bonded and grounded in order to

Answer 12

drain off static charges

Question 13

How many engine driven fuel pumps per engine are required for engines requiring fuel pumps?

Answer 13

One fuel pump for each engine

Question 14

A typical lathe transport aircraft fuel manifold system allows how many of the following?
1. All tanks can be serviced through a single connection
2. Any engine can be fed from any tank
3. All engines can be fed from all tanks simultaneously
4. A damaged tank can be isolated from the rest of the fuel system

Answer 14

1,2,3 and 4

Question 15

A fuel system must be designed to prevent fuel vapor ignition caused by

Answer 15

lightning

Question 16

What is the minimum distance allowed between a fuel tank and the fire wall separating the engine?

Answer 16

One-half inch

Question 17

Fuel baffles are installed in tanks to prevent _____ caused by changes in attitude of the aircraft

Answer 17

Surging

Question 18

Many fuel tanks incorporate ______ valves to prevent fuel from flowing away from the boost pump or tank outlet when the aircraft is in a high “G” maneuver.

Answer 18

flapper

Question 19

Fuel heaters are used with systems for turbine engines to prevent ______ in the fuel from clogging system filters

Answer 19

ice crystals

Question 20

A transducer in a fuel pressure system serves what function?

Answer 20

Converts fluid pressure directly through a transmitter to the indicator

Question 21

The use of turbine fuels has resulted in some problems not normally associated with aviation gasoline. One of the problems is

Answer 21

Microbial contaminants

Question 22

What is used in many aircraft to prevent bubbles in the fuel after it leaves the tank when atmospheric pressure is lower than fuel vapours pressure

Answer 22

Boost pumps

Question 23

Which of the following precautions is most important during refuelling operations?

Answer 23

Fuel to be used must be appropriately identified

Question 24

Before fuelling an aircraft by using the pressure fuelling method, what important precaution should be observed?

Answer 24

The truck pump pressure must be correct for that refuelling system

Question 25

What flight safety-related advantage does a pressure fuelling system provide?

Answer 25

Reduces the chances for fuel contamination

Question 26

Aircraft pressure fueling system instructional procedures are normally placarded on the

Answer 26

fuel control panel access door

Question 27

Pressure fueling of aircraft is usually accomplished through

Answer 27

at least a single point connection

Question 28

Which of the following may be used for the repair of fuel leaks on most integral fuel tanks?

Answer 28

Riveting and resealing

Question 29

How is the outlet fuel pressure regulated on a submerged, single-speed, centrifugal-type fuel pump?

Answer 29

By the pumps design and internal clearance

Question 30

What is one purpose of a fuel tank vent?

Answer 30

To maintain atmospheric pressure

Question 31

When inspecting a removable rigid fuel tank for leaks, what procedure should be followed?

Answer 31

Pressurize the tank with air and brush with soapy water

Question 32

If it necessary to enter an aircraft fuel tank, which procedure should be avoided?

Answer 32

Conduct the defueling and tank purging operation in an air-conditioned room

Question 33

What is recommended practice for cleaning a fuel tank before welding?

Answer 33

Steam clean the tank interior

Question 34

An aircraft integral fuel tank is

Answer 34

a part of the aircraft structure

Question 35

Which gas is used for purging an aircraft fuel tank?

Answer 35

Carbon dioxide

Question 36

Why is the main fuel strainer located at the lowest point in the fuel system?

Answer 36

It traps any small amount of water that may be present in the fuel system

Question 37

The purpose of a diaphragm in a van type fuel pump is to

Answer 37

compensate fuel pressures to altitude changes

Question 38

When moving the mixture control on a normally operating engine into the idle cutoff position, engine RPM should

Answer 38

slightly increase before the engine starts to die

Question 39

Entrained water in aviation in aviation turbine fuel is a hazard because of its susceptibility to freezing as it passes through the filters. What are common methods of preventing this hazard?

Answer 39

Anti-icing fuel additives

Question 40

As a general rule, which statement is true regarding fuel leaks?

Answer 40

Stains, seeps and heavy seeps, (in addition to running leaks) are considered flight hazards when located in unvented areas of the aircraft

Question 41

The presence of fuel stains around a fuel nozzle would indicate

Answer 41

clogged fuel nozzle

Question 42

What should be used to inert an integral fuel tank before attempting repairs

Answer 42

CO2

Question 43

What should be used to remove flux in aluminum tank after welded repairs?

Answer 43

5 percent solution of nitric or sulfuric acid

Question 44

What method would be used to check for internal leakage of a fuel valve without moving the valve from the aircraft?

Answer 44

Place the valve in the OFF position, drain the strainer bowl, and with booster pump on, watch to see if duel flows to the strainer bowl

Question 45

Why are jet fuels more susceptible to water contamination that aviation gasoline?

Answer 45

Jet fuel has a higher viscosity than gasoline

Question 46

When installing a rigid fuel line, 1/2 inch in diameter, at what intervals should the line be supported?

Answer 46

16 inches

Question 47

The probe of a capacitance type fuel level gauge is essentially a

Answer 47

capacitor with fuel and air as a dielectric

Question 48

Which statement concerning electronic type fuel quantity indicating system is true?

Answer 48

It has no moving parts in the tank

Question 49

What type of remote reading fuel quantity indicating system has several probes installed in each fuel tank?

Answer 49

Electronic

Question 50

Which aircraft fuel quantity indicating system incorporates a signal amplifier?

Answer 50

Electronic

Question 51

A drip gauge may be used to measure

Answer 51

the amount of fuel in the tank

Question 52

The electronic type fuel quantity indicating system consists of a bridge circuit

Answer 52

an amplifier, an indicator, and a tank unit

Question 53

A probe or a series of probes is used in what kind of fuel quantity indicating system?

Answer 53

Capacitor

Question 54

Why is the capacitance fluid quantity indicating system more accurate in measuring fuel level than a mechanical type?

Answer 54

It measures by weight instead of volume

Question 55

One advantage of electrical and electronic fuel quantity indicating systems is that

Answer 55

several fuel tank levels can be read on one indicator

Question 56

A fuel totalizer is a component which indicates the

Answer 56

amount of fuel in all tanks

Question 57

A digital fuel totalizer automatically indicates the amount of fuel used, fuel remaining, current rate of consumption and fuel

Answer 57

weight aboard at takeoff

Question 58

What is the dielectric (nonconducting material) in a capacitance-type fuel quantity indicating system?

Answer 58

Fuel and air in the tank

Question 59

A capacitance-type fuel quantity indicating system measures fuel in

Answer 59

pounds

Question 60

What are the four general type of fuel quantity gauges?

Answer 60

Sight glass, mechanical, electrical and electronic

Question 61

How does temperature affect fuel weight?

Answer 61

Cold weight is heavier per gallon

Question 62

One advantage of electrical and electronic fuel indicating systems is that the indicator

Answer 62

can be located any distance from the tanks

Question 63

When fuel quantity is measured in pounds instead of gallons, the measurement will be more accurate because fuel volume

Answer 63

varies with temp change

Question 64

An electrical type fuel quantity indicating system consists if an indicator in the cockpit and a float

Answer 64

in the tank that moves a connecting arm to the wiper on a variable resistor in the tank

Question 65

What is the purpose of a float operated transmitter installed in a fuel tank?

Answer 65

It sends an electrical signal to the fuel quantity indicator

Question 66

In an electronic type fuel quantity indicating system, the tank sensing unit is a

Answer 66

capacitor

Question 67

What must each fuel quantity indicator be calibrated to read during level fight when the quantity of fuel remaining is equal to the unusable fuel supply

Answer 67

Zero

Question 68

What unit would be adjusted to change the fuel pressure warning limits?

Answer 68

Pressure-sensitive mechanism

Question 69

Select one means of controlling the fuel temperature on turbine powered aircraft

Answer 69

Engine bleed air to a heat exchanger

Question 70

What is the purpose of flapper type check valves in integral fuel tanks?

Answer 70

To prevent fuel from flowing away from the boost pumps

Question 71

What unit is generally used to actuate the fuel pressure warning system?

Answer 71

Pressure-sensitive mechanism

Question 72

What method is used on turbine powered aircraft to determine when the condition of the fuel is approaching the danger of forming ice crystals?

Answer 72

Fuel temperature indicator

Question 73

Which of the following would give the first positive indication that a change over from one fuel tank to another is needed?

Answer 73

Fuel pressure warning

Question 74

A fuel pressure warning switch contacts close and warning lights is turned on when

Answer 74

the fuel pressure drops below the specified limits

Question 75

A transmitter in a fuel pressure warning system serves what function?

Answer 75

Converts fluid pressure to an electrical signal

Question 76

Where is fuel pressure taken for the pressure warning signal on most aircraft engines?

Answer 76

Fuel pressure line of the carburetor

Question 77

Which of the following is necessary to effectively troubleshoot a fuel pressure warning system?

Answer 77

The manufacturer's maintenance manuals

Question 78

Which of the following would be most useful to locate and troubleshoot an internal fuel tank in an aircraft fuel system?

Answer 78

Maintenance manual diagram and descriptions

Question 79

In some aircraft with several fuel tanks, the possible danger of allowing the fuel supply in one tank to become exhausted before the selector valve is switched to another tank is prevented by the installation of

Answer 79

a fuel pressure warning signal system

Question 80

The function of a fuel heater is to

Answer 80

protect the engine fuel system from ice formation

Question 81

1. Gas turbine engine fuel systems are very susceptible to the formation of ice in the fuel filters 2. A fuel heaters operates as a heat exchanger to warm the fuel

Answer 81

Both No.1 and No.2 are true

Question 82

No. 1 A fuel heater can use engine bleed as a source of heat No.2 A fuel pressure gauge indicates the pressure of the fuel entering the carburetor

Answer 82

Both No.1 and No.2 are true

Question 83

A fuel pressure relief valve is required on an aircraft

Answer 83

Positive displacement fuel pump

Question 84

The primary purpose of a fuel tank sump is to provide a

Answer 84

place for contaminants and water to settle, with a drain valve to remove the impurities

Question 85

Why are integral tanks used in many large aircraft?

Answer 85

to reduce weight

Question 86

When an aircraft is fueled from a fuel truck or fuel farm that has not been contaminated, daily draining

Answer 86

of strainers and sumps is combined with periodic filter changes and inspection to ensure fuel is contaminant free

Question 87

When defueling an aircraft, which of the following must be accomplished?

Answer 87

Always defueled outside the hangar

Question 88

Integral fuel tanks on transport aircraft are

Answer 88

supported by the aircraft structure

Question 89

What precautions must be observed if a gravity feed fuel system is permitted to supply fuel to an engine from more than one tank at a time

Answer 89

The tank airspaces must be interconnected

Question 90

The purpose of a baffle plate used in a fuel tank is to

Answer 90

resist fuel surging within the fuel tank

Question 91

What markings must be placed on or near each appropriate fuel filler cover on standard category aircraft?

Answer 91

The word 'Avgas' and the minimum fuel grade

Question 92

What is one disadvantage of using aromatic aviation fuels?

Answer 92

Deteriorates rubber parts

Question 93

Fuel boost pumps are operated

Answer 93

to provide positive flow of fuel to the engine

Question 94

Flapper valves are used in fuel tanks to

Answer 94

act as a check valve

Question 95

Why are centrifugal type boost pumps used in fuel systems of aircraft operating at high altitude?

Answer 95

To supply fuel under pressure to engine-driven pumps

Question 96

Why is it necessary to vent all aircraft fuel tanks?

Answer 96

To limit pressure differential between the tank and atmosphere

Question 97

According to 14 CFR (FAR) Part 23, what minimum required must be placed at or near each appropiate fuel filler cover for reciprocating engine-powered aircrafts?

Answer 97

the word 'Avgas' and the minimum fuel grade

Question 98

What angle should a fuel filler neck (gooseneck) be to ensure positive pressure?

Answer 98

90 degrees

Question 99

The location of leaks and defects within the internal portions of the fuel system can usually be determined by

Answer 99

observing the pressure gauge and operating the selecting valves

Question 100

What type of fuel-booster pump requires a pressure relief valve?

Answer 100

Sliding vane

Question 101

To prevent vapor lock in fuel lines at high altitude, some aircraft are equipped with

Answer 101

booster pumps

Question 102

Some turbine powered aircraft have fuel temperature indicator located in the cockpit to

Answer 102

monitor the fuel temp at high altitude flight

Question 103

When inspecting a fuel system, you should check all valves located downstream of boost pumps with the pumps

Answer 103

operating

Question 104

The type of fuel boost pump that separates air and vapour from the fuel before it enters the line to the carburetor is the

Answer 104

centrifugal type pump

Question 105

On a large aircraft pressure refuelling system, a pressure refuelling receptacle and control panel will perit one person to

Answer 105

fuel or defuel any or all fuel tanks of an aircraft

Question 106

When routing a fuel line between two rigidly mounted fittings the line should

Answer 106

have at least one bend between such fittings

Question 107

Which of the following tests can determine an aviation gasoline tendency to vapor lock?

Answer 107

Reid vapor pressure test

Question 108

Microbial growth is produced by various of micro-organisms that live and multiply in the water interfaces of jet fuels. Which of the following could result if microbial growth exists in a jet fuel tank and is not corrected?

Answer 108

Interference with fuel flow, interference with fuel quantity indicators and electrolytic corrosive action in a metal tank

Question 109

The vapor pressure of aviation gasoline is

Answer 109

lower than vapor pressure of autmotive gasoline

Question 110

What can be done to eliminate or minimize the microbial growth problem in an aircraft jet fuel tank

Answer 110

Use anti-icing and antibacterial additives

Question 111

Microorganisms form a biofilm that can clog filters, corrode tank coatings and degrade the fuel. They can be controlled by somewhat with the addition of what to the fuel?

Answer 111

Biocides

Question 112

What is the maximum vapor pressure allowable for an aircraft fuel?

Answer 112

7PSI

Question 113

If a bladder type fuel tank is to be left empty for an extended period of time, the inside of the tank should be coated with a film of

Answer 113

engine oil

Question 114

How may the antiknock characteristics of a fuel be improved?

Answer 114

by adding a knock inhibitor