M15.1

Question 1

What are the units of force in all technical manuals?

Answer 1

Decanewton

Question 2

What is the unit for weight?

Answer 2

Newtons

Question 3

How is work measured?

Answer 3

Force multiplied by distance

Question 4

How is power measured?

Answer 4

Work over time

Question 5

What is Newton’s first law?

Answer 5

A body at rest will stay at rest unless acted upon

Question 6

What is Newton’s third law?

Answer 6

Every action has an equal and opposite reaction

Question 7

What is the working cycle of a gas turbine?

Answer 7

• induction (suck)
• compression (squeeze)
• combustion (bang)
• exhaust (blow)

Question 8

What are the different types of gas turbine engines on an aircraft?

Answer 8

• turbojet
• turboprop
• turbofan
• APU

Question 9

What is the APU used for?

Answer 9

Electrical and pneumatic power

Question 10

What is an engine that uses jet propulsion called?

Answer 10

A reaction engine (they use newtons law of motion)

Question 11

What year did Hans Von Ohain build a gas turbine engine with a radial turbine?

Answer 11

1937

Question 12

What year did Frank Whittle build a engine with an axial turbine?

Answer 12

1941

Question 13

Why aren’t turbojet engines used commonly anymore?

Answer 13

They’re very loud and not very efficient

Question 14

What is special about the turboprop combine to the turbojet and turbofan?

Answer 14

It can be driven directly by the compressor shaft or by a free turbine and a long centre drive shaft

Question 15

What is used to reduce the high gas turbine engine rotation to speeds the propeller can handle?

Answer 15

A reduction gear

Question 16

How much gas energy is converted into torque on a turboprop engine?

Answer 16

All of it

Question 17

A turbofan engine converts a large part of the gas energy into torque to drive the fan and the engine compressor. Where does the rest go?

Answer 17

It is directly converted into thrust

Question 18

The total thrust of the turbofan engine is what?

Answer 18

The sum of thrust from the core and fan

Question 19

What is the bypass ratio?

Answer 19

It is the ratio of air that flows through the fan duct compared to the core engine

Question 20

Why aren’t prop-fan engines used commonly?

Answer 20

They’re difficult to mount to the wings

Question 21

How much fuel percentage do prop-fan engines save combined to turbofan engines?

Answer 21

20%

Question 22

What are the two types of engine design?

Answer 22

Modular and non-modular

Question 23

What’s the difference between modular and non-modular?

Answer 23

Modular is split into sub modules and non modular is one whole piece

Question 24

What is aluminium alloy manly used for?

Answer 24

Gearbox housings, fan stator casing and low loaded parts of the fan module

Question 25

Where is ceramic used?

Answer 25

In the combustion chamber and the high pressure turbine

Question 26

Why is ceramic used?

Answer 26

It is a good heat and corrosion protection system

Question 27

What are steel alloys used for?

Answer 27

The N1 drive shaft, bearing, and main structural frames on some engines

Question 28

Where is cobalt found in an engine?

Answer 28

They’re found in the first stage of the high pressure turbine

Question 29

Where is titanium mainly used?

Answer 29

In the fan, low pressure compressor and front stages of the high pressure compressor

Question 30

Where is nickel used in an engine?

Answer 30

The high pressure compressor, the combustion section and. For the turbines