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arbu ration C I 22j

Question 42 (in database)

If you suspect carburettor icing when flying

an

aircraft whose engine is not fitted with a

carburettor air-temperature gauge, the correct action would be:

a) to select the appropriate amount of carburettor heat depending on the amount of icing

suspected.

,

cl to always select

fYJ 1

carburettor he the engine starts to run roughly, at which point the

carburettor heat snoulcibe

~ e d o

com.

d)

to open the throttle to make up for the lost poW§{. •

The correct answer

is b.

Question 39 (in database)

It is possible

1 

get carburettor icing when the relative humidity is grealer than 50 within a

temperature range of:

b) -710 +33°C.

cl -20 1 +1O°C.

d) al any temperature.

The cor re ct answer is b.

Question 37 (in database)

Some carburettors are fitted with a diffuser which:

a) prevents the mixture becoming too lean as the RPM increases,

b) prevents the mixture becoming too lean as the RPM decreases.

c) prevents the m   becoming too rich as the RP increases.

d ) prevents the

~ m i J l 9 . . .

s the RPM decreases.

The correct answer IS c. lJ

Question 40 (in database)

On a fixed pitch propeller aircraft whose engine

is

fitted with a carburettor, the indications of

induction system icing are:

a a grad ,'

~

and possible ro gh nnlng and

vlbra

Ion.

b) a sudden drop in

ReM   t F T I ~ e r a t u r e .

c) a rise

in

manifold pressure and a reduction

in

ai -speed,

in

level ~

d)

a rise

in

engine oil temperature and a fall

in

oil press re.

The correct answer

is

a.

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Question 45 (in database)

Detonation could result from using :

a) too weak a mixture .

d) too high an RPM

J i o " - : :- :1 A G S

The correct answer is a. G-

Question 29 (in database)

The significance of using the chemically correct mixture

of

air and fuel is that:

a) it

is

the one used.

b)

I, 15 1

by

o l u m . "'-G---=-1AGS

c) it allows complete combustion to occur.

d) it gives the best results.

The correct answer is

c.

Question

34

(in database)

As you climb, altitude and density

Th

e weight of air entering the engine

and, therefore, the mixture will be

a) increases decreases increases richer

b) increases

gecreases

decreases

c)

decreases ina eases decreases

d) increases - ~ : ;  

~ G : -

l ~

weaker

The correct answer is b,

Question

4

in database)

On

a constant speed propeller aircraft whose engine is fitted with a carburettor, the indications

of

induction system icing are:

a) a

,',e

1   , " , e aod a ,edu"'oo 1 ale,peed, ~ flight.

b)

that opening th . ttle

, : : : :   ~

rrJrease engine RPM.

c)

a gradual drop in engine

RPM and

possible rough running

and

vibration.

d) a drop

in

manifold pressure or a reduction

in

air-speei1,

in

level flight.

T

he

correct answer is d.

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Question

3 in

database)

Pra-ignition:

a) is also known as pinking.

b) occurs after ignition,

c) is usually ~ a hot spot in the combustion h a m

o

~

_ ~

,

d) happens after . pari< occl LrS.J t ~ ( P . g.

Tha correct answer IS

o

U

Question 30 in database)

Detonation is:

a) explosive, 2 ~ combustion.

b) an explosion thlt:

urs oeff j : ~ l ignition point.

c) usually associated with a rich mixture and high cylinder head temperature.

d) usually associated with a weak mixture and a low cylinder head temperature .

The correct answer is a.

Question 47 in database)

Pre-ignition in a four stroke piston engine is:

a) caused by a rich mixture in a hot engine.

b) the fuel air mixture burning earlier than it should.

c) the explosive

cO

mbustion of the fuel-air mixture .

,

,

d) characterised by. e ringing u c ~ explosion it causes.

The correct answer IS b. U

Question 33 in database)

It

is best to run the engine with the mixture:

,

b) slightly rich, as

th

excess l i ~ f N the engine.

c) slightly rich,

as

the excess air helps cool the engine .•

d) slightly weak, as the excess air helps cool the engine.

The correct answer is b.

•

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Question 38 (in database)

An accelerator pump is used to prevent a flat spot .

A

flat spot is:

a) when the throttle is opened quickly and the demand for fuel cannot be met immediately.

b) when the throttle is closed quickly and the engine is starved of fuel.

c) when the t h r o t t l

~

opened quickly and the mixture

b e c o

 

t e m p o r a r i l y

too rich.

d) when the t h r o t t l ~ closed apd t

The correct answer is a. 1 1

Question 278 (in database)

re becomes temporarily too rich.

When the Idle Cut Off valve on a light aircraft piston engine is operated it:

,

a) switches fuel om the ma in carburettor

jet

to the'slow running jet.

b it stops fuel l o w ~ .rum th: (j; Aa . rettor je t and slops the engine.

c) it stops the fuel flow from the slow running jet a i d SlOPS the engine.

d it cuts off the fuel supply to the float chamber

of

the carburettor.

The correct answer is c.

Question 367 (in database)

In the engine fuel system, what is the relationship between the ambient pressure in the float

chamber of a carburettor and the static pressure in a carburettor's venturi?

a) The static pressure in the venturi will

be

greater than the ambient pressure in the float

chamber.

b) There is

no

diffe1e , because the terms ambient and static pressure have the same

.

,

meaning.

\ . ~ ~ I , . : : ~

c) T

he

static pressure in the

~ r ~ ~ g ~ l o w e r

than the ambient pressure in the float chamber.

d Both pressures are equal.

T

he

correct answer is c

Question 28 (in database)

The chemically correct ratio for air to fuel is

15:1

by weight. What, however, is the approximate

air-fuel ratio for the optimum mixture strength for use in a piston engine?

b) 8:1 by

l u m e ·

  : 5 J ' - - : : G ~ _ ~ l

AGS

c) 9: 1 by weight.

d

12:1 by weight.

The correct answer is d.

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Question 46 (in database)

Airflow through the venturi of a carburettor causes a:

a) rise in pressure and a drop in velocity at the narrowest point.

b) drop in pressure and a rise

in

temperature at the narrowest point.

c) drop

in p r e s s u r

  ~ rise

in

velocity at the nar

(o

west

p ?int.

d) drop

in p r e s s u d r o p ~

.::, loc

i f f9

t the narrowest point.

The correct answer IS c.

1 '\

Question 35 (in database)

Having reached the top of a climb, when flying an aircraft fitted with a fixed pitch propeller, the

mixture should

be

adjusted for the cruise. One way of doing this is to:

a) lean the mixture until the RPM rises then falls slightly, then make the mixture richer until the

RPM rises and: falls slightly once more.

b) lean the

mixtll9

t i l the RPM rises then falls slightly.

c) make the mixture richer untf ttrek

~

then falls slightly, then make the mixture leaner

until the RPM rises and falls slightly once more.

d) adjust the mixture until the RPM rises to its maJlimum"available value.

The correct answer is a.

Question 43 (in database)

While taJlying in an aircraft fitted with a

fi

xed pitch propeller, you suspect that

you

have

carburettor icing. The correct action to take would bs to:

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Question

36

(in database)

As

air enters the restriction of a Venturi , velocity static or ambient pressure

od

temperature _ .

a) increases increases

b) increases ecteases

G

~ ~ ~

c) decreases increases decreases

d) decreases decreases increases

The correct answer

is b.

Question 44 (in database)

Which of the options below gives the most complete picture

of

the atmospheric conditions

contributing to a high risk

of

carburettor icing?

a) Humid, or hazy weather, flying close to doud, or flying in rain or drizzle.

,

b) Humid, cloudy,

 p p g g y ~ e

f ~ l j ~ close to cloud,

or

flying

in

rain or drizzle.

c) Humid air at temperatures below

O·C.

d) Flying in cloud, rain or drizzle.

The correct answer

is b.