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• mitchell_de
• Topic Author

### mitchell_de created the topic: calculating maximum payload

Hi Guys,

I recently bought the revised for the 2nd of December CPL performance book and have been working through it. I've just got up to the calculating maximum payload section and have been confused by some of the examples.

In figure 5.6 you are calculating maximum T/O weight with minimum fuel and to calculate minimum fuel at T/O you use trip fuel in kg plus 27.2kg, which I'm confused about where you got the 27.2kg from (there is no explanation).

Then in figure 5.11, you are calculating maximum cargo by first calculating maximum T/O weight, in this example to calculate fuel at T/O you multiply trip fuel by 1.1 and add 41 ( which aligns with your fuel policy of 10% contingency fuel and 45 minutes of final reserve).

Finally, in exercise 5.4 the answers go back to adding 27.2kg to the trip fuel to find fuel at T/O.

I do not understand why it is different and especially why it is 27.2kg, with my exam coming up I would love some help in why it is this way.

Thanks, Mitch

• Posts: 2468

### bobtait replied the topic: calculating maximum payload

Mitch
Thanks for your feed-back. In the process of amending the books to the Dec 2nd CASA changes, it looks like something slipped through in the Performance Book. A few of the examples and question answers had an incorrect calculation of the fixed reserve for air transport flights. I have made the necessary changes to the e-text and also posted an errata on our web page. Please find attached the amended pages. The 27.2kg for fixed reserve was based on 30 minutes instead of 45 minutes and 10% contingency fuel required for air transport. That has now been addressed in the next print of the book.

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File Name: PAGE137_195.pdf
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