Systems exam this month........feedback
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Systems exam this month........feedback
1.Generators are connected
• in parallel to increase voltage
• in parallel to increase power
• in series to increase voltage
• in series to increase power
2.Alternators are connected in
• parallel
• series
• dependant upon engine
• dependant upon generator
3. Measurements of real and reactive loads in an ac generator are
• watts and amps
• amps and volts
• KVA and KVR
3.When testing a fire detection system
• the lights only are tested
• the extinguishers only are tested
• the detection loops only are tested
• the lights and the loops are tetsted
4. When the mixture lever is pulled to lean
• air flow to the combustion chamber reduces
• fuel flow to the combustion chamber reduces
• air flow to the carburettor reduces
• fuel flow to the carburettor reduces
5. Torsional loads in an aircraft wing are caused by?
• Dihedral
• Wing tip vortices
• Positive sweep
6.The pressure relief valve in oxygen system
• reduces pressure in the tank so the the pressure in the manifold is at a reasonable level for the user
• is used following the failure of the normal pressure reducing valva
7.regarding a diluter demand system, oxygen is
• mixed with air in the passengers mask (not crew)
• received when the user inhales
8.a question about engine capacity I think with the likeliest answer (I think)
• Vloume per cylinder x number of cylinders
9.what mixture would give max egt?
• 1:9
• 1:1/15:1
• cruise settin
• idle
CAN ANYONE REMEMBER ANYMORE??
• in parallel to increase voltage
• in parallel to increase power
• in series to increase voltage
• in series to increase power
2.Alternators are connected in
• parallel
• series
• dependant upon engine
• dependant upon generator
3. Measurements of real and reactive loads in an ac generator are
• watts and amps
• amps and volts
• KVA and KVR
3.When testing a fire detection system
• the lights only are tested
• the extinguishers only are tested
• the detection loops only are tested
• the lights and the loops are tetsted
4. When the mixture lever is pulled to lean
• air flow to the combustion chamber reduces
• fuel flow to the combustion chamber reduces
• air flow to the carburettor reduces
• fuel flow to the carburettor reduces
5. Torsional loads in an aircraft wing are caused by?
• Dihedral
• Wing tip vortices
• Positive sweep
6.The pressure relief valve in oxygen system
• reduces pressure in the tank so the the pressure in the manifold is at a reasonable level for the user
• is used following the failure of the normal pressure reducing valva
7.regarding a diluter demand system, oxygen is
• mixed with air in the passengers mask (not crew)
• received when the user inhales
8.a question about engine capacity I think with the likeliest answer (I think)
• Vloume per cylinder x number of cylinders
9.what mixture would give max egt?
• 1:9
• 1:1/15:1
• cruise settin
• idle
CAN ANYONE REMEMBER ANYMORE??
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This is what we came up with....
(wording is not exact on all questions but is as far as I remember it)
1. A bi metallic strip fire warning is delayed,
a) To allow for vibration
b) To wait for another warning
c) To wait for temp to stabilize
2. An accumulator is charged to 1200psi, when the system pressurizes to 3000psi the gauge on the gas side of the accumulator will indicate?
a) 1200 psi
b) 1500 psi
c) 3000 psi
d) 4200 psi
3. If cabin pressure is showing -200ft, at FL290
a) Max cabin altitude will be reached and the pressure relief valve will be opened.
4. APU is used is on the ground and can be used in flight for:
a) Air conditioning and Electrics
b) Electrics only
c) Air conditioning only
d) ???????
5. Apart from energy storage what does a Hydraulic accumulator do?
a) Store Pressure
b) ??
c) Store fluid
d) Compensate for Pa surges in the system
6. A distributor distributes
a) A high voltage from the primary coil to the spark plug
b) A high amperage from the primary coil to the spark plug
c) A high voltage from the secondary coil to the spark plug
d) A high amperage from the secondary coil to the spark plug
7. In the main landing gear strut
a) Forces are damped by nitrogen
b) Forces are damped by a viscous fluid
c) Forces are damped by nitrogen and a viscous fluid
d) Forces are damped by air
8. Multiple engine A/C fire warning
a) Light and unique Bell for each engine
b) Light for each and 1 bell
c) Bell for each engine and 1 light
d) Light for each and 1 bell
9. After the power stroke which valves are open?
a) Inlet
b) Inlet and Outlet
c) Outlet
d) None
10. On a cold day just after start you notice a slightly high oil pressure this is,
a) Normal as long as it settles soon after
b) Abnormal and the engine should be shut down immediately
c) Indicates that the oil needs changing
d) Abnormal and the flight can continue as long as a mechanic is notified
11. The reason for twist on a propeller is,
a) To increase the tip speed
b) To have increase the lift at the root
c) To have an even pressure across the entire blade surface
12. Where is the strainer
a) Upstream of the Needle valve
b) Upstream of the diffuser
c) Downstream of the diffuser
13. If the elevator jams on a servo tab
a) Total loss of control
b) Control reversal
c) Heavy stick forces
14. A Mach trimmer is used to prevent?
a) The nose down in supersonic flight
15. On a Subsonic A/C the C.P moves. (Mach No. high)
a) To the trailing edge
b) To the trailing edge
c) Midway of the wing
16. In some aircraft the outboard ailerons are locked out when?
a) The aircraft speed is high and the flaps are up
b) The gear is up
17. Kruger flaps are located?
a) On the trailing edge outboard
b) On the leading edge outboard
c) Trailing edge inboard
d) Leading edge outboard
(wording is not exact on all questions but is as far as I remember it)
1. A bi metallic strip fire warning is delayed,
a) To allow for vibration
b) To wait for another warning
c) To wait for temp to stabilize
2. An accumulator is charged to 1200psi, when the system pressurizes to 3000psi the gauge on the gas side of the accumulator will indicate?
a) 1200 psi
b) 1500 psi
c) 3000 psi
d) 4200 psi
3. If cabin pressure is showing -200ft, at FL290
a) Max cabin altitude will be reached and the pressure relief valve will be opened.
4. APU is used is on the ground and can be used in flight for:
a) Air conditioning and Electrics
b) Electrics only
c) Air conditioning only
d) ???????
5. Apart from energy storage what does a Hydraulic accumulator do?
a) Store Pressure
b) ??
c) Store fluid
d) Compensate for Pa surges in the system
6. A distributor distributes
a) A high voltage from the primary coil to the spark plug
b) A high amperage from the primary coil to the spark plug
c) A high voltage from the secondary coil to the spark plug
d) A high amperage from the secondary coil to the spark plug
7. In the main landing gear strut
a) Forces are damped by nitrogen
b) Forces are damped by a viscous fluid
c) Forces are damped by nitrogen and a viscous fluid
d) Forces are damped by air
8. Multiple engine A/C fire warning
a) Light and unique Bell for each engine
b) Light for each and 1 bell
c) Bell for each engine and 1 light
d) Light for each and 1 bell
9. After the power stroke which valves are open?
a) Inlet
b) Inlet and Outlet
c) Outlet
d) None
10. On a cold day just after start you notice a slightly high oil pressure this is,
a) Normal as long as it settles soon after
b) Abnormal and the engine should be shut down immediately
c) Indicates that the oil needs changing
d) Abnormal and the flight can continue as long as a mechanic is notified
11. The reason for twist on a propeller is,
a) To increase the tip speed
b) To have increase the lift at the root
c) To have an even pressure across the entire blade surface
12. Where is the strainer
a) Upstream of the Needle valve
b) Upstream of the diffuser
c) Downstream of the diffuser
13. If the elevator jams on a servo tab
a) Total loss of control
b) Control reversal
c) Heavy stick forces
14. A Mach trimmer is used to prevent?
a) The nose down in supersonic flight
15. On a Subsonic A/C the C.P moves. (Mach No. high)
a) To the trailing edge
b) To the trailing edge
c) Midway of the wing
16. In some aircraft the outboard ailerons are locked out when?
a) The aircraft speed is high and the flaps are up
b) The gear is up
17. Kruger flaps are located?
a) On the trailing edge outboard
b) On the leading edge outboard
c) Trailing edge inboard
d) Leading edge outboard
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This is what i think the answers were to your feedback Moku!!
1.B
2.C
3.A
4. the questiion had more about bein able to use one or the other in an emergency situation
5.D
6.C
7.B
8.B
9.C
10.A
11.C
12.A
13.B
14.dont remember seein that question!
15.dont remember that one either!
16.A
17.Leadin edge inboard
dont know if theyre right though...........Not very optamistic about this exam.............already know ive got 10 questions wrong!!!!
1.B
2.C
3.A
4. the questiion had more about bein able to use one or the other in an emergency situation
5.D
6.C
7.B
8.B
9.C
10.A
11.C
12.A
13.B
14.dont remember seein that question!
15.dont remember that one either!
16.A
17.Leadin edge inboard
dont know if theyre right though...........Not very optamistic about this exam.............already know ive got 10 questions wrong!!!!
Regarding question 10)...I put b) Abnormal and the engine should be shut down immediately. I thought the oil pressure was more likely to be low on a cold day (i.e. take longer to rise). I figured that high oil p. on any day would most likely mean a PRV problem.
...and for 7) I put a) Forces are damped by nitrogen. My thinking on this one was that the oil controls recoil and the gas absorbs the force of landing (dampen)?
I was originally most concerned about all the questions on magnetos, EPR's and the like but now I'm questioning everything!
9:18
...and for 7) I put a) Forces are damped by nitrogen. My thinking on this one was that the oil controls recoil and the gas absorbs the force of landing (dampen)?
I was originally most concerned about all the questions on magnetos, EPR's and the like but now I'm questioning everything!
9:18
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9-18,
Q10. On a cold day the oil will be thicker ( one reason why your car turns over slower on a cold day ) although the pressure will be higher ( until it warms up) your oil flow around the engine will be reduced ( more wear to your engine in the first 5 minutes than 100 miles or more warm). Normal.
Q7. I've referenced this one and found the answer to be ' Gas and fluid'. Now i am confused, can someone clarify please.
D.J.
Q10. On a cold day the oil will be thicker ( one reason why your car turns over slower on a cold day ) although the pressure will be higher ( until it warms up) your oil flow around the engine will be reduced ( more wear to your engine in the first 5 minutes than 100 miles or more warm). Normal.
Q7. I've referenced this one and found the answer to be ' Gas and fluid'. Now i am confused, can someone clarify please.
D.J.
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Q7.....yes your right.....Air supports the aircraft and oil dampens the recoil......but given the option of both and havin seen the question in feedback a while back and also bein told by our instructor to go for nitrogen and viscous fluid, i took the option and went with him!!!Even though, mentally, i know its wrong!
Hey, i dont know if its right and im sure loads of my other answers are wrong!
19:18......i had loadsa questions i was unsure about in the exam and now im almost certain i got all of em wrong!!
What about the mixture question:
What air:fuel mixture gives highest EGT?
1:9
1:1/15:1
cruie power
idle
2 marker that baby aswell!!
Hey, i dont know if its right and im sure loads of my other answers are wrong!
19:18......i had loadsa questions i was unsure about in the exam and now im almost certain i got all of em wrong!!
What about the mixture question:
What air:fuel mixture gives highest EGT?
1:9
1:1/15:1
cruie power
idle
2 marker that baby aswell!!
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RowleyUK,
The mixture that will give you the highest EGT is going to be the weakest mixture, so I would have thought that Idle and cruise was out. Between 1:9 and 1:15 I would have gone for latter, 15 parts air to 1 part fuel. could be wrong though, sure someone will correct me.
D.J.
The mixture that will give you the highest EGT is going to be the weakest mixture, so I would have thought that Idle and cruise was out. Between 1:9 and 1:15 I would have gone for latter, 15 parts air to 1 part fuel. could be wrong though, sure someone will correct me.
D.J.
I'm very confused now. Is that question worded correctly?
What air:fuel mixture gives highest EGT?
a) 1:9
b) 1:1/15:1
c) cruise power
d) idle
I believe the highest EGT will be at the leanest working mixture setting, so...
a) 1:9 air:fuel is exceptionally rich!
b) 1:1 is still very rich 15:1 is relatively lean
c) cruise power (is NOT a mixture setting but, I think, my answer see below)
d) idle (is also NOT a mixture setting but the mixture needs to be fairly rich for cooling purposes)
I think I may have put c) cruise power thinking that at cruise power I would have leaned the mixture correctly and thus would have the highest EGT!
What on earth is the answer to this one?
What air:fuel mixture gives highest EGT?
a) 1:9
b) 1:1/15:1
c) cruise power
d) idle
I believe the highest EGT will be at the leanest working mixture setting, so...
a) 1:9 air:fuel is exceptionally rich!
b) 1:1 is still very rich 15:1 is relatively lean
c) cruise power (is NOT a mixture setting but, I think, my answer see below)
d) idle (is also NOT a mixture setting but the mixture needs to be fairly rich for cooling purposes)
I think I may have put c) cruise power thinking that at cruise power I would have leaned the mixture correctly and thus would have the highest EGT!
What on earth is the answer to this one?
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More Q's
More q's from this months awful systems exam
1. How is a starter motor connected?
A) Series wound
B) Shunt wound
C) Compound wound
D) Wounded up
2. What happens to the temp, pressure and velocity in a centrifugal compressor?
A) Temp decrease, pressure decrease, velocity increase
B) Temp increase, pressure increase, velocity decrease
C) Temp, pressure and velocity increase
D) ???
3. What happens when you put the magneto switch to OFF?
(it could have been ON, tho i think there was another question similar in layout talking about what happens when it is ON)
A) Secondary circuit grounds
B) Primary circuit opens
C) Secondary circuit opens
D) Primary circuit grounds
4. Before entering a pump why is the fuel slightly pressurised?
A) To prevent vapour locks
B) To prevent pump cavitation
C) ??
D) ??
5. What is the order of a bootstrap system?
A) Primary heat exchanger, secondary heat exchanger, turbine, compressor
B) Primary heat exchanger, compressor, secondary heat exchanger, turbine
C) ????
D)????
I got this one using 'Pamela's C*** Smells Terrible'
6. What is the correct arrangement in an axial flow compressor?
A) Stator, rotor, stator
B) Rotor, stator
C) Stator, rotor
D) Rotor, stator, rotor
1. How is a starter motor connected?
A) Series wound
B) Shunt wound
C) Compound wound
D) Wounded up
2. What happens to the temp, pressure and velocity in a centrifugal compressor?
A) Temp decrease, pressure decrease, velocity increase
B) Temp increase, pressure increase, velocity decrease
C) Temp, pressure and velocity increase
D) ???
3. What happens when you put the magneto switch to OFF?
(it could have been ON, tho i think there was another question similar in layout talking about what happens when it is ON)
A) Secondary circuit grounds
B) Primary circuit opens
C) Secondary circuit opens
D) Primary circuit grounds
4. Before entering a pump why is the fuel slightly pressurised?
A) To prevent vapour locks
B) To prevent pump cavitation
C) ??
D) ??
5. What is the order of a bootstrap system?
A) Primary heat exchanger, secondary heat exchanger, turbine, compressor
B) Primary heat exchanger, compressor, secondary heat exchanger, turbine
C) ????
D)????
I got this one using 'Pamela's C*** Smells Terrible'
6. What is the correct arrangement in an axial flow compressor?
A) Stator, rotor, stator
B) Rotor, stator
C) Stator, rotor
D) Rotor, stator, rotor
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yes the mixture one is the exaxct wording!!
A nice typical,fair,CAA type question id say!!!
Chintito,
Your Q2 referred to what happens to the temperature and velocity of air as it passes through the diffusor of a CF compressor......... In which case i would say:
V Decreases and T Increases P Increases too
Had it not mentioned the word diffusor then i would have gone for the
V inc T inc P inc
Chintitos q's
1.A
2.
3.D
4.B
5.B although the answers werent as straight forward as that........answers in the region of Secondary heat exchanger and turbinbe
6.B
1:1/15:1 expressed as :one to one fifteenth to one!! Stupid i know.......but im sure i could remember oxford mentioning this question on my brush up course......that is the chemically correct mixture for a piston engine......wether it will give max EGT is another issue!!!
6.
A nice typical,fair,CAA type question id say!!!
Chintito,
Your Q2 referred to what happens to the temperature and velocity of air as it passes through the diffusor of a CF compressor......... In which case i would say:
V Decreases and T Increases P Increases too
Had it not mentioned the word diffusor then i would have gone for the
V inc T inc P inc
Chintitos q's
1.A
2.
3.D
4.B
5.B although the answers werent as straight forward as that........answers in the region of Secondary heat exchanger and turbinbe
6.B
1:1/15:1 expressed as :one to one fifteenth to one!! Stupid i know.......but im sure i could remember oxford mentioning this question on my brush up course......that is the chemically correct mixture for a piston engine......wether it will give max EGT is another issue!!!
6.
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Chintito question 4 on fuel pressure. The correct answer is "A" - to prevent vapour lock. What they are getting at I believe is the need for LP and HP fuel pumps. Between the tanks and the engine the fuel lines often pass through unpressurised parts of the aircraft so to prevent vapour lock LP pumps are fitted at the tank. The pump cavitation answer is more to do with hydraulics I believe. Please feel free if I am wrong (I dont have my notes infront of me).
I got 79% in Feb systems - hope you all get the passes you are after.
I got 79% in Feb systems - hope you all get the passes you are after.
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Guys,
Regarding the question...
What air/fuel mixture gives highest EGT?
I seem to recall that the answers are more like...
a) 1:9
b) 1:15
c) At a mixture setting close to the idle cut off setting
d) ?
I stand to be corrected...
FM
Regarding the question...
What air/fuel mixture gives highest EGT?
I seem to recall that the answers are more like...
a) 1:9
b) 1:15
c) At a mixture setting close to the idle cut off setting
d) ?
I stand to be corrected...
FM
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FM,
That would be more like it. 15/1. But please anyone else who can remember, please tell us.
D.J.
p.s. I will run this one by Keith williams, I'm sure we'll get the full jist of it.
D.J.
That would be more like it. 15/1. But please anyone else who can remember, please tell us.
D.J.
p.s. I will run this one by Keith williams, I'm sure we'll get the full jist of it.
D.J.
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Right chaps,
This is it........Ive worked it out!!
What AIR:FUEL Mixture will allow the max EGT??
A..Near Idle cut off
B.. 1:9
C..1:1/15:1
D..Cruise settin
Now if you read the question they have asked for Air to Fuel (as in exam) now this means that the Max EGT will be gained from 15:1 but that is not an option......... However,If you look at 1:1/15:1........
Complicated explanantion......
If you have 1 part of air but only a 'one fifteenth' of fuel.......then by the time you manage to get all the 'fifteenths of fuel' (ie, make a whole one) then you will also have accumalated 15 parts of air at the same time.....therefore you have an air:Fuel mixture of 15:1!!!
Its not 1:9 cos that would be far too rich!! 1part of air to 9 parts fuel?? I dont think so!
Cruise will be leaned so i cant see that being the answer!
Anyway i went for C.......im pretty sure its right!!
This is it........Ive worked it out!!
What AIR:FUEL Mixture will allow the max EGT??
A..Near Idle cut off
B.. 1:9
C..1:1/15:1
D..Cruise settin
Now if you read the question they have asked for Air to Fuel (as in exam) now this means that the Max EGT will be gained from 15:1 but that is not an option......... However,If you look at 1:1/15:1........
Complicated explanantion......
If you have 1 part of air but only a 'one fifteenth' of fuel.......then by the time you manage to get all the 'fifteenths of fuel' (ie, make a whole one) then you will also have accumalated 15 parts of air at the same time.....therefore you have an air:Fuel mixture of 15:1!!!
Its not 1:9 cos that would be far too rich!! 1part of air to 9 parts fuel?? I dont think so!
Cruise will be leaned so i cant see that being the answer!
Anyway i went for C.......im pretty sure its right!!
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Hi all,
According to Keith williams, the question on Highest EGT has been challanged. Keith seems to think that the 1:1/15:1 is a mistype error, and should have read 1:15 fuel/air. That would then make sense, and for you lot a better chance of passing ( marks should be awarded, what ever answer you put).
Good look.
D.J.
According to Keith williams, the question on Highest EGT has been challanged. Keith seems to think that the 1:1/15:1 is a mistype error, and should have read 1:15 fuel/air. That would then make sense, and for you lot a better chance of passing ( marks should be awarded, what ever answer you put).
Good look.
D.J.
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Test of knowledge or test of taking tests?
If this is the general form of these exams I'd not relish sitting them! I'd be happy just to finish let alone pass.
In the interests of those who might, here is my reasoning:
Not Idle - both carburation and fuel-injection have mechanisms to ensure slow running w/o the engine stopping - idle jet and fuel control unit respectively will ensure a richer and so cooler mixture at idling revs (hence the pre-takeoff check that the engine does idle and not stop).
Not 1:9 - 1 part air to 9 parts fuel will not ignite! Funnily enough a ratio of 9 air to 1 fuel is the approximate stoichiometric ratio for burning ethanol (according to Google) but note the ratio inversion for this piece of knowledge that may become slightly less useless in future.
Cruise setting - Possibly correct answer except 1) this is not a ratio and 2) actual power settings are usually expressed as a certain RPM or RPM&MP at a particular EGT rich of peak i.e. the mixture is indeed leaned but not to highest or peak EGT.
1:1/1:15 - Most likely answer. 1) the number 15 is close to the key number for a stoichiometrically correct mixture for burning gasoline of 14.7 parts air and 1 part fuel by WEIGHT (volume differs according to temp and pres) and 2) if you do the algebra you get the ratio:
1:1/1:15 IET (1/1) / (1/15) IET (1/1) * (15/1) IET (15/1) IET 15:1
NB. IET means "is equivalent to".
Also, several text books mention the 1:15 ratio for efficient burning but not explicitly for peak EGT burning which anyway according to most engine manufacturer's operating manuals is probably not the most efficient for reaching TBO hence their recommendations of ROP for cooler and longer operation (lean of peak is a whole other discussion).
Answer: out of "cruise" or "1:15" I'd go for the second. Even if the CAA/JAA intended you to "see" the algebra I'd say it was a bit naughty as a "systems" question.
I usually start with AP3456 when looking for references. Highly recommended but anyone have others?
In the interests of those who might, here is my reasoning:
Not Idle - both carburation and fuel-injection have mechanisms to ensure slow running w/o the engine stopping - idle jet and fuel control unit respectively will ensure a richer and so cooler mixture at idling revs (hence the pre-takeoff check that the engine does idle and not stop).
Not 1:9 - 1 part air to 9 parts fuel will not ignite! Funnily enough a ratio of 9 air to 1 fuel is the approximate stoichiometric ratio for burning ethanol (according to Google) but note the ratio inversion for this piece of knowledge that may become slightly less useless in future.
Cruise setting - Possibly correct answer except 1) this is not a ratio and 2) actual power settings are usually expressed as a certain RPM or RPM&MP at a particular EGT rich of peak i.e. the mixture is indeed leaned but not to highest or peak EGT.
1:1/1:15 - Most likely answer. 1) the number 15 is close to the key number for a stoichiometrically correct mixture for burning gasoline of 14.7 parts air and 1 part fuel by WEIGHT (volume differs according to temp and pres) and 2) if you do the algebra you get the ratio:
1:1/1:15 IET (1/1) / (1/15) IET (1/1) * (15/1) IET (15/1) IET 15:1
NB. IET means "is equivalent to".
Also, several text books mention the 1:15 ratio for efficient burning but not explicitly for peak EGT burning which anyway according to most engine manufacturer's operating manuals is probably not the most efficient for reaching TBO hence their recommendations of ROP for cooler and longer operation (lean of peak is a whole other discussion).
Answer: out of "cruise" or "1:15" I'd go for the second. Even if the CAA/JAA intended you to "see" the algebra I'd say it was a bit naughty as a "systems" question.
I usually start with AP3456 when looking for references. Highly recommended but anyone have others?
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Dean,
Another question being challenged????
The question specifically said Air:Fuel..........hence thats why the answer was algebraically reversed.......I understand its unfair and is nothin more than a play on words!!
I cant see this as bein a 'typo'........its obviuosly a trick question as it was the only question in the exam which was worth 2marks!
Hows about this for a bad question:
After the power stroke, which valves are open?
A. Inlet
B. Outlet
C. Inlet and Outlet
D. None
There is no mention of valve lag or lead and also no mention of the position of the piston.......Hence now there can be two answers........
The outlet is open......but then the inlet valve also opens at the top of the exhaust stroke (which is after the power stroke).........
but are they talkin about what valves are open immiediately after the power stroke??? in which case it would be outlet!!
Its tricky, its unfair and its bang out of order, all because somebody cant be a***d sittin down and checkin what the questions are actually asking!!!!
Another question being challenged????
The question specifically said Air:Fuel..........hence thats why the answer was algebraically reversed.......I understand its unfair and is nothin more than a play on words!!
I cant see this as bein a 'typo'........its obviuosly a trick question as it was the only question in the exam which was worth 2marks!
Hows about this for a bad question:
After the power stroke, which valves are open?
A. Inlet
B. Outlet
C. Inlet and Outlet
D. None
There is no mention of valve lag or lead and also no mention of the position of the piston.......Hence now there can be two answers........
The outlet is open......but then the inlet valve also opens at the top of the exhaust stroke (which is after the power stroke).........
but are they talkin about what valves are open immiediately after the power stroke??? in which case it would be outlet!!
Its tricky, its unfair and its bang out of order, all because somebody cant be a***d sittin down and checkin what the questions are actually asking!!!!
Join Date: Sep 2002
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RowleyUK,
I see what your saying, but I don't think your quite right on that one. If the question was, as stated. i.e. AFTER the power stroke then it can only be the Outlet valve. After the power stroke the piston would be at BDC, anything before that would be DURING the power stroke.
Good thread, its opened my eyes somewhat.
D.J.
I see what your saying, but I don't think your quite right on that one. If the question was, as stated. i.e. AFTER the power stroke then it can only be the Outlet valve. After the power stroke the piston would be at BDC, anything before that would be DURING the power stroke.
Good thread, its opened my eyes somewhat.
D.J.