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Clarification on GS (home) value in final test question

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flyer created the topic: Clarification on GS (home) value in final test question

I refer to Q3 of CPL final test in the textbook. I have obtained the same value of TAS (193kts) similar to the answer. However, looking at the answer, it seems that the Groundspeed Home used in the ETP calculation is 217kts, which is 24kts headwind. Using my flight computer and the given crosswind component, I only obtained a value of 12 kts headwind, and thus 205 kts as my groundspeed home. Can I get clarification as to how the 217kts was computed?
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Stuart Tait replied the topic: Clarification on GS (home) value in final test question

G'day Flyer

The clarification is I was having a bad day :) I must have mixed up the working with another question. Thanks for the feedback we appreciate it.

See revised below: (have changed the selection as well)



Cheers
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MEADE1990 replied the topic: Clarification on GS (home) value in final test question

May I just jump on his wagon for a "moment"

I'm busily working my way through all these balance issues you guys have spent a lot of time coming up with and I stumble across this doozey (see attachment).

Consistantly, the "ARM" in all of these problems so far have been whole numbers rounded up or down. This .5 shows up and the difference is 11kg!!! [ex 5.13 Q3]

Can I get clarification on rounding (from you lovely folk or otherwise?)

Meade
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bobtait replied the topic: Clarification on GS (home) value in final test question

If the weight is to be added or subtracted to the auxiliary tanks, a decimal point does make a difference because the difference between the auxiliary tanks and the aft limit is such a small number (120mm) when you divide a decimal point makes a bigger difference. I can't believe that the examiner is going to argue about a decimal point of a mm. However, it would be safe if you included the decimal point in that case. If you are adding or subtracting weight to any other station but the auxiliary tanks, a decimal point makes no significant difference.

In the current version of the book, I have ignored the decimal points for the sake of consistency. The exam applies margins to the 'perfect' answer according to the individual question. I doubt if you would lose a mark over one an a half litres of fuel.

You would have to have a most amazing dip stick!!
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MEADE1990 replied the topic: Clarification on GS (home) value in final test question

G'day Bob!

Thanks for taking the time! greatly appriciated.

Therfore would you concur that if I went to one decimal place for all arm's that I would be safe in the exam?

The "SHIFT" difference im working on is "5" (from a present arm of 2674.5 rounded up to the nearest whole number) and the difference is 15.2L of fuel? You have said 1.5L, does that mean im doing this wrong? (still)

An error of 15L (more) would put my little 140 well under the required climb gradiant on a warmish day :)

Meade
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