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- MEADE1990
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- Posts: 24
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Hi Folks,

Hoping I can get a little help here…

The attachment for question 8, take a quick look. Doesnt that answer go against anything we've learnt/legal. My under standing is the Minimum fuel is the minimum and closest to nothing below the minimum?

My real drama is with Q18. Im a bit of a numpty, so I did it the long way converting both to UTC as follows:

A)

0500-0844=2016

1830-0944=0846

Then once these two answers are subtracted from each other I end up with 11.5hrs, which is not an answer? Would someone be so kind and let know as to why im not getting this one right?

Many thanks,

Meade

Hoping I can get a little help here…

The attachment for question 8, take a quick look. Doesnt that answer go against anything we've learnt/legal. My under standing is the Minimum fuel is the minimum and closest to nothing below the minimum?

My real drama is with Q18. Im a bit of a numpty, so I did it the long way converting both to UTC as follows:

A)

0500-0844=2016

1830-0944=0846

Then once these two answers are subtracted from each other I end up with 11.5hrs, which is not an answer? Would someone be so kind and let know as to why im not getting this one right?

Many thanks,

Meade

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- John.Heddles
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- ATPL/consulting aero engineer

- Posts: 507
- Thank you received: 48

All's well, you just need to think a bit about what's going on.

Q1.

The workings are close enough.

Now your problem is interpretation of what the question is asking. Your logic is fine but we are dealing with exam-style questions, not what we might do in the real world.

So, the question, itself, asks for the answer which is**closest to the calculated answer**. No problem - that's 135 litres.

Would I go with 135 litres ? Of course not, I would want at least 137 and a bit. So had the question asked something along the lines of which answer**both is acceptable operationally and closest to the minimum fuel I might launch with,** again, no problem - 143 litres

Q2.

Workings are OK.

Perhaps if you check your subtraction again ? You've just subtracted the wrong way around. Try it this way ...

0846 is 2400 + 0846 = 3246.

3246 - 2016 = 12.30

Q1.

The workings are close enough.

Now your problem is interpretation of what the question is asking. Your logic is fine but we are dealing with exam-style questions, not what we might do in the real world.

So, the question, itself, asks for the answer which is

Would I go with 135 litres ? Of course not, I would want at least 137 and a bit. So had the question asked something along the lines of which answer

Q2.

Workings are OK.

Perhaps if you check your subtraction again ? You've just subtracted the wrong way around. Try it this way ...

0846 is 2400 + 0846 = 3246.

3246 - 2016 = 12.30

Engineering specialist in aircraft performance and weight control.

Last Edit: 6 months 1 week ago by John.Heddles.

The following user(s) said Thank You: MEADE1990

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- MEADE1990
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G'day John,

Thanks again for the reply, I really appriciate it.

What prompts you to add the extra 24hrs to point B to get to 3246?

Keen for your reply!

Meade

Thanks again for the reply, I really appriciate it.

What prompts you to add the extra 24hrs to point B to get to 3246?

Keen for your reply!

Meade

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- John.Heddles
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- ATPL/consulting aero engineer

- Posts: 507
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You are subtracting the BOD at A from the EOD at B with both adjusted to the same clock reference.

So, available daylight hours is 0846 - 2016. How you effect the subtraction is up to yourself.

For me, the time for B is a day ahead so I add the day (converted to hours gives 24 hours) for the subtraction and Robert's your father's brother.

Engineering specialist in aircraft performance and weight control.

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- DaveT2762
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Just in reference to the available time it does identify that it is for flight, hence the question is whether this should also consider the minimum 30mins reduction planning condition associated with EOD.

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- John.Heddles
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Methinks you try to make too much of the question.

The question clearly is interested in determining the chart daylight difference. In the same way as with the fuel calculations, how we might apply the data operationally might well be different. However, the question is after the straightforward extraction of data from the AIP charts.

Were the question to have been worded a little differently, then the answer might end up being a little different.

It is important for the exams that you focus on answering the question. Recall that the answer is to a dumb computer "tick the box" approach so you don't have the luxury of giving additional information, qualifications, caveats, etc. The mantra must be KISS and aim for maximising the mark for the exam. Somewhere along the line, the theory and flight instructor team has to address the sometimes subtle differences between what the examiner reasonably can ask, and how .... and what is required in the real world of operations.

That's the flying game ... the quicker you adjust to the rules of the game, the happier a life you will enjoy as a pilot.

The question clearly is interested in determining the chart daylight difference. In the same way as with the fuel calculations, how we might apply the data operationally might well be different. However, the question is after the straightforward extraction of data from the AIP charts.

Were the question to have been worded a little differently, then the answer might end up being a little different.

It is important for the exams that you focus on answering the question. Recall that the answer is to a dumb computer "tick the box" approach so you don't have the luxury of giving additional information, qualifications, caveats, etc. The mantra must be KISS and aim for maximising the mark for the exam. Somewhere along the line, the theory and flight instructor team has to address the sometimes subtle differences between what the examiner reasonably can ask, and how .... and what is required in the real world of operations.

That's the flying game ... the quicker you adjust to the rules of the game, the happier a life you will enjoy as a pilot.

Engineering specialist in aircraft performance and weight control.

Last Edit: 6 months 1 week ago by John.Heddles.

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- DaveT2762
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John,

Thanks for the comments.

It think it was simply the introduction of the word 'Flight' into the question that made me head towards that attributed point of consideration.

Thanks for the comments.

It think it was simply the introduction of the word 'Flight' into the question that made me head towards that attributed point of consideration.

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- John.Heddles
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- ATPL/consulting aero engineer

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...and that's great because it shows that you are thinking about things.

Just a problem that, sometimes, folks make the exam type questions too complicated and it all turns upside down ...

Just a problem that, sometimes, folks make the exam type questions too complicated and it all turns upside down ...

Engineering specialist in aircraft performance and weight control.

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