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Fuel for flight

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MissSoph created the topic: Fuel for flight

Just wanting to have some clarification to make sure I’m not missing something….. . Yep… can you tell I’m starting to question every teenie tiny detail about performance….
So the Echo has say, operating weight of 1979kg moment index of469.4 … the question goes on to give me row 1, row 2, row 3, wing, rear compartment, and then also tells me that the minimum fuel required for the flight is 140kg.I can use 5 kg hard ballast if I need to, and I’m asked to find minimum weight of ballast fuel that is required in the main tanks.
The info about the fuel… that, in this instance is not really info I needed to know… is just something nice they have told me…
If they had said the gross weight however was…. I would have to remember to take the weight of the fuel out to check its in balance at the Zero fuel weight ?
Do I have that correct ?
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MissSoph replied the topic: Fuel for flight

MissSoph wrote: Just wanting to have some clarification to make sure I’m not missing something….. . Yep… can you tell I’m starting to question every teenie tiny detail about performance….
So the Echo has say, operating weight of 1979kg moment index of469.4 … the question goes on to give me row 1, row 2, row 3, wing, rear compartment, and then also tells me that the minimum fuel required for the flight is 140kg.I can use 5 kg hard ballast if I need to, and I’m asked to find minimum weight of ballast fuel that is required in the main tanks.
The info about the fuel… that, in this instance is not really info I needed to know… is just something nice they have told me…
If they had said the gross weight however was…. I would have to remember to take the weight of the fuel out to check its in balance at the Zero fuel weight ?
Do I have that correct ?

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MissSoph replied the topic: Fuel for flight

Just thought I’d pop the question in… Q16…. So the fuel required for the flight was just a bonus piece of info…. As he asks me for min amount of ballast fuel to be loaded
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John.Heddles replied the topic: Fuel for flight

Perhaps you can post your answer and working for some discussion ?

Also, folks need to keep in mind that, unless everyone is looking at the exact same version of the book, book references can present a problem. Perhaps, generally, better to post the specific question so there is no ambiguity ?

Engineering specialist in aircraft performance and weight control.
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bobtait replied the topic: Fuel for flight

That question has two unrelated parts. Firstly you must solve the balance problem with ballast fuel and hard ballast.

The trip fuel (once called flight fuel) is given just to allow you to check the possibility that after you have calculated the ballast required (flow chart calculation) and loaded the ballast, will you be over the landing weight limit at the destination? (beetle diagram problem).

You will never be asked such a question in an exam, but I put it in just for fun!!
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John.Heddles replied the topic: Fuel for flight

Firstly you must solve the balance problem with ballast fuel and hard ballast.

Therein lies a problem, as the question indicates that you can't alter the loading, ie that would preclude the use of sand bags. Hence my interest in seeing Sophie's solution.

Perhaps it might be preferable to alter the question detail slightly ?

Engineering specialist in aircraft performance and weight control.
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bobtait replied the topic: Fuel for flight

I'm pretty sure the question says "You can't alter the present loading". That is you can't shift any of the present items. I can see that the wording can be ambiguous so I'll change the wording to make it less so.

Bob
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John.Heddles replied the topic: Fuel for flight

.. sometimes you just need to allow for dumbos like me, unfortunately ...

Engineering specialist in aircraft performance and weight control.
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MissSoph replied the topic: Fuel for flight

Thanks Bob…. I thought that may be the case… but can you tell I’m really quite anxious now about this exam… I’m just wanting to make sure I’m not in any way getting tricked up… ;)
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