Fuel penalty question.

The correct answer is listed as 22781 kg.

The question gives two different fuel penalties, one "based on TOM" which is +166kg and one "based on LM" which is +199kg.

Interestingly, I worked it out using the +166kg figure and got the same answer.

Can someone please clarify why you have used the one based on landing mass? Is it because the landing mass is the limiting mass (19000kg)?.

Could someone also check my working?

Penalty is 166kg per 1000kg extra fuel.

Therefore useful remaining on board would be 834kg (1000-166).

Penalty ratio is 834/1000 = 0.834.

To calculate how much ADDITIONAL fuel we can uplift based on this, I use one of two methods, either this formula:

i.e. Maximum fuel uplift = 19000kg / 0.834 = 22781kg.

or else I reason it out

This method gives the correct answer in this question, and also the other fuel penalty question.

I cannot understand the reasoning given in the explanation of this question, which uses the "based on landing mass" figure of +199kg.

Using this figure and either of the two methods above, the answer would be

It does not really matter if you get to select the answer, but for type in, it might be a problem.

Can someone please clarify why the 199kg was used, and the reasoning behind the calculationg method used in the explanation? (19000 / 1000 x 199).

Thanks!

The correct answer is listed as 22781 kg.

The question gives two different fuel penalties, one "based on TOM" which is +166kg and one "based on LM" which is +199kg.

Interestingly, I worked it out using the +166kg figure and got the same answer.

Can someone please clarify why you have used the one based on landing mass? Is it because the landing mass is the limiting mass (19000kg)?.

Could someone also check my working?

__Calculating penalty "based on TOM" of +166kg__Penalty is 166kg per 1000kg extra fuel.

Therefore useful remaining on board would be 834kg (1000-166).

Penalty ratio is 834/1000 = 0.834.

To calculate how much ADDITIONAL fuel we can uplift based on this, I use one of two methods, either this formula:

**Maximum fuel uplift = remaining landing mass available / penalty ratio**i.e. Maximum fuel uplift = 19000kg / 0.834 = 22781kg.

or else I reason it out

**19000kg = 83.4%, therefore what is 100%?**

100 x 19000 / 83.4 = 22781kg.100 x 19000 / 83.4 = 22781kg.

This method gives the correct answer in this question, and also the other fuel penalty question.

**BUT**I cannot understand the reasoning given in the explanation of this question, which uses the "based on landing mass" figure of +199kg.

Using this figure and either of the two methods above, the answer would be

**23720kg**It does not really matter if you get to select the answer, but for type in, it might be a problem.

Can someone please clarify why the 199kg was used, and the reasoning behind the calculationg method used in the explanation? (19000 / 1000 x 199).

Thanks!

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