Ad Third Class Exam

Front 1

Jet Propulsion is defined as
A. A decrease in velocity and increase in pressure
B. The propelling force generated in the direction opposite to the flow of a mass of gas or liquid under pressure
C. the propelling force generated in the same direction of the flow of mass of gas or liquid under pressure
d. force x distance

Back 1

B

Front 2

Divergent Duct decreases the velocity and increases the pressure
True or False

Back 2

True

Front 3

Force is defined as
A. rate of doing work
B. capacity for doing work
C. action on a body that changes its state of motion
D. quanity of matter in a body measured in relation to its inertia

Back 3

C

Front 4

Mass is defined as
A. rate of doing work
B. capacity for doing work
C. action on a body that changes its state of motion
D. quanity of matter in a body measured in relation to its inertia

Back 4

D

Front 5

Power is defined as
A. rate of doing work
B. capacity for doing work
C. action on a body that changes its state of motion
D. quanity of matter in a body measured in relation to its inertia

Back 5

A

Front 6

Energy is defined as
A. rate of doing work
B. capacity for doing work
C. action on a body that changes its state of motion
D. quanity of matter in a body measured in relation to its inertia

Back 6

B

Front 7

The english measurement for mechanical power is
A. Slug
B. Horse power
C. Work
D. All of the above

Back 7

B
Note Slug is a measuring unit for mass

Front 8

Work = F X D. What do the F and D stand for?

Back 8

Force times Distance

Front 9

A Standard day Consists of
A. 0 Inch of mercury, 0% humidity and temp. of 59 degrees
B. 29.92 Inch of mercury, 0% humidity and a temp. of 69 degrees.
C. 29.92 Inch of mercury, 0% humidity and a temp. of 59 degrees.

Back 9

C

Front 10

More air arriving at the intake then the engine can ingest is
A. turbulence
B. Ram effect
C. friciton pressure loss
D. ram recovery

Back 10

B
Note Ram recovery is the airspeed at which ram pressure rise is equal to friction pressure loss

Front 11

What are Newtons three laws?

Back 11

1st law-inertia
2nd law- force is proportional to the product of mass and acceleration
3rd law- for every action there is an opposite and equal reaction

Front 12

Which of the following groups of jet engines as an ad will you be associated with most?
A. Rocket, turbojet, turboshaft, and turbo
B. turbojet, turboshaft, turboprops and turbofan
C. P-3, F-18, J-52 and props
D. none of the above

Back 12

B

Front 13

In the engine designation J79-GE-10 what does the 10 represent?
A. Basic Engine type
B. Manufacturer symbol
C. Model Number
D. Nothing

Back 13

C
Note
J - basic engine type
79- is arbitrary
GE- manufacturer symbol

Front 14

What are the four types of engines?

Back 14

Turbojet, pulsejet, ramjet and rocket

Front 15

Which of the following is a reason for proper air entrance (duct) design?
A. To reduce the ratio of compressor discharge pressure to duct inlet pressure
B. To increase the ratio of ram pressure to duct inlet turbulence
c. to reduce the ratio of ram pressure to duct inlet turbulence
D. To increase ram recovery while reducing pressure drops

Back 15

D

Front 16

During supersonic flight what major aircraft component can not withstand supersonic velocity airflow?
A. the tail section
B. The engine
C. the intake
D. the wings

Back 16

B

Front 17

The compressor's major function is to supply air to the combustion chamber in the proper quantity and pressure.
True or False

Back 17

True
Note the secondary function of the compressor is to supply bleed air for various engine and aircraft systems.

Front 18

A ten stage, axial flow compressor consists of what total number of rotors and stators
A. 5 and 5
B. 5 and 10
C. 10 and 10
D. 10 and 5

Back 18

C

Front 19

In an axial flow engine, by what means is high velocity, low pressure air converted to low velocity, high pressure air?
A. Action of a single intake diffuser
B. Action of stator blades at each stage of compression
C. Action of rotor blades at each stage of compression
D. Design of the intake

Back 19

B

Front 20

The Angle of attack is the angle at which airflow
A. strikes the rotor blade
B. strikes the stator blade

Back 20

A

Front 21

A stall due to an excess volume of air in the rear of the compressor is
A. choking
B. ground rpm limit
C. stalling
D. split spool

Back 21

A

Front 22

The 3 engine operating parameters that cause the airflow angle of attack to vary are engine rpm, compressor inlet temp. and compressor discharge pressure.
True or False

Back 22

True

Front 23

Guide vanes change the direction of the air entering and leaving the compressor in what manner?
A. By swirling it as it enters and leaves
B. By straightening it out as it enters and leaves
C. By swirling it as it enters and straightening it out as it leaves
D. By straightening it out as it enters and swirling it as it leaves.

Back 23

C

Front 24

What are the two common forms of blade roots?

Back 24

Fir-tree and bulb

Front 25

What is the primary function of the combustion section?
A. to provide ignition
B. to drive the turbine
C. to drive the compressor
D. to burn the fuel-air mixture

Back 25

D

Front 26

What percent of air entering the combustion chamber is mixed with fuel for combustion?
A. 40%
B. 75%
C. 25%
D. 100%

Back 26

C

Front 27

What percent of air serves as flame control?

Back 27

75%

Front 28

Which of the following is not a basic type of combustion chamber?
A. Annular
B. Can-Annular
C. Basket chamber
D. Multiple-chamber

Back 28

C

Front 29

What total number of combustion liners are used in jet engines using can-type combustion chambers?
A. 1 or 2
B. 6 or 7
C. 8 or 10
D. 11 or 13

Back 29

C

Front 30

What types of fuel nozzles are used in jet engines?

Back 30

simplex and duplex
Note Duplex is most widely used

Front 31

In the can type combustion chamber, where are the spark ignitor plugs located?
A. In the two lower chambers
B. In the right and left chambers
C. In the two upper chambers
D. All of the above

Back 31

A

Front 32

In the Can-type combustion chamber liner what is the purpose of the holes in the dome?
A. to help atomize fuel
B. to drain unburned fuel
C. to admit cooling air into the chamber
D. to admit primary air into the chamber

Back 32

C

Front 33

What is the main function of the inlet section of the annular combustion chamber?
To change velocity energy into pressure
or
to change velocity energy into mechanical energy

Back 33

to change velocity energy in to pressure

Front 34

The preswirl vanes in the can annular combustion chambers help to
A. reduce turbulence
B. mix the air and fuel
C. increase axial air velocity

Back 34

B

Front 35

The turbine converts velocity energy in to what?
A. mechanical energy
B. pressure
C. heat energy

Back 35

A

Front 36

The sole function of the turbine is to drive the compressor and accessories.
True or false

Back 36

True

Front 37

What is the function of the exaust section?
To direct hot gas out of the aircraft and increase exause gas temperature to obtain higher exaust velocity
or
to direct hot out of the aircraft while increasing velocity and preventing turbulence

Back 37

To direct hot gas out of the aircraft and increase exause gas temperature to obtain higher exaust velocity

Front 38

What part of the exaust section increases pressure and decreases velocity?
A. Exaust cone
B. inner cone
C. jet nozzle

Back 38

A

Front 39

Which of the following is an important function of the radial struts in the exaust cone assembly?
A. to straighten the exaust gases
B. to brace the exaust shroud
C. to increase the exaust gas pressure
D. to vary the size of the exaust opening

Back 39

A

Front 40

The size of the exaust section exit area directly effects the operating temp. of the engine and performance.
True or False

Back 40

True

Front 41

The primary function of the afterburner is
A. increase engine efficiency
B. increase thrust for specific conditions
C. to burn fuel not burned in the combustion chamber

Back 41

B