Hello Everyone,

I have read the performance book and so far I understand the majority of the formulas except a certain part on page 108 excersise 4.11. For example in question 1 you just take the flight fuel away from the total fuel whereas in question 3 you need to add the reserves to the flight fuel prior to subtracting it from total fuel. Reading a post in regards to echo loading questions Mr. Tait summed up when to use the load chart or flow chart etc which made life easier. I am just wondering if anyone has a simple way to know when to add reserves to flight fuel or remove from total etc.

Kind regards,

Fred

The exercise you refer to is a drill exercise where you are given the flight fuel [the fuel you will actually burn during the flight] and you are asked to find the minimum fuel that must be on board at start up. In every case you use the formula Flight Fuel x 1.15 + 15 + 3 = minimum fuel required.

However, sometimes you may be given the total fuel in the tanks [when you dip the tanks before start up] and you may be asked to find how much of that fuel you can plan to burn during flight. In that case, you use the formula [Total Fuel on board - 15 - 3] ÷ 1.15 = Flight Fuel available.

When you want the minimum fuel required you take the flight fuel and MULTIPLY by 1.15 first then ADD the reserves and allowances.
When you want to know the flight fuel available given the total fuel on board you SUBTRACT the reserves and allowances FIRST then DIVIDE by 1.15.

Thank you very much for that clear explanation!