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Question 1

What percentage of compressor discharge air enters the primary vs secondary combustion zone?

Answer 1

Primary 20%, Secondary 80%

Question 2

“Annular” combustion chamber types, when compared with “can-annular” types, have the advantage of being more space efficient, suffer less pressure loss, and can be shorter in length:

Answer 2

True

Question 3

Turboprops and Turbofans normally have:

Answer 3

A greater number of turbine stages than a pure jet type

Question 4

Approximately what percentage of core gas stream energy in a pure turbo jet is extracted by the turbine to drive the compressors?

Answer 4

50%

Question 5

In a turbofan power-plant, the highest velocity of the gas stream occurs:

Answer 5

At the turbine nozzle guide vanes

Question 6

“Stagger angle” in a turbine blade:

Answer 6

Straightens the gas flow path, and ensures that all parts of the blade extract equal energy

Question 7

“Fir tree” turbine blade attachments:

Answer 7

Ensure that centrifugal load is equally shared by all the fir tree serrations

Question 8

Which statement is most correct?

Answer 8

In each turbine “stage” each nozzle guide vane is hotter than its associated
turbine blade but less prone to creep stress

Question 9

Turbine blade lengths on later turbine stages:

Answer 9

Are longer than on earlier turbine stages

Question 10

The engine is being started on a very cold day and it will be the first flight of the day. The oil is very thick. Which answer is most correct?

Answer 10

The high oil viscosity would cause the oil filter bypass valve to open. Unfiltered
oil would be supplied to the user units, with the exception of the effect of the
“last chance filters”

Question 11

Which answer correctly describes the requirement for fuel quantity?

Answer 11

A minimum of 2 separate checks, differing by no more than 3% of the larger amount

Question 12

Multiple fuel feed stand-pipes are provided to:

Answer 12

Various parts of the wing fuel tank to assure continuous fuel supply during aircraft manoeuvre

Question 13

LOW pressure fuel boost pumps are:

Answer 13

Submerged in the fuel tank, are electrically powered, and lubricated and cooled by the fuel

Question 14

The high pressure fuel pump:

Answer 14

Is mounted on the cold section of the engine, and driven by the high pressure
compressor shaft

Question 15

Use of vaporising tubes in a combustion chamber:

Answer 15

Allows more stable combustion at low engine RPM

Question 16

Except in an emergency, fuel can NOT be jettisoned (dumped) below:

Answer 16

6000ft agl