G'day everyone,

I'm halfway through reading Bob Tait's CPL Performance book and couldn't help it but freak out with the amount of information! Even if that was all there was for Performance, it would already be the hardest subject in my opinion.

Before moving on to chapter 5, I'd like to ask something about PNR and ETP. How are we supposed to remember that formula?? and do we get questions as hard as Question 8 on page 4.51 (involving GNMPG, Met and that PNR formula).

I guess I'll get used to it.. but at first glance it looks pretty hard.

And one more thing, a more objective question now, in the book it says that we will not be required to work out ECHO's Climbing TAS and ROC from that table in the actual CASA exam. But what happens to cruise speeds and fuel flow? are they also given in the exam or are we going to have that table given to us and be expected to consult it? Just wondering what to expect..

That's it for now, Thank you!

Question 8 on page 4.51 is way beyond what the exam would ask. It was put there for those who enjoy a challenge. ETP/PNR questions will require that you can apply the formula - which is not all that hard Distance to ETP = Total distance x GS home ÷ twice TAS. Or Time to PNR = Safe endurance x GS home ÷ twice TAS.

All CASA questions will give you the required TAS or climb rates in the question text. I have based book questions on using the supplement TAS tables and Climb tables simply because that's the way you would have to do it in practice if you were planning a high performance aircraft on a fuel critical flight. In that regard, the CASA questions are quite a bit easier than the book examples.

Great news, thanks Bob!

Hmmm sorry Bob but I can't understand where the 41kg come from when working out the fixed reserve + holding to establish the MTOW (page 5.5). Do you always assume that figure as holding + fixed reserve to calculate minimum fuel? does it mean 60 min holding + 45 min reserve?
Thank you

The fixed reserve is 15 gallons. So, since 1 gallon = 2.72 kg [See ERSA GEN-CON-2] 15 gallons is 15 x 2.72 = 41 kg. Also the taxi allowance is 3 gallons which is 3 x 2.72 = 8 kg.

Fuel required is always = Flight fuel x 1.15 + fixed reserve + holding + taxi
If you work in gallons that is Flight fuel x 1.15 + 15 + holding + 3
In you work in kilos that is Flight fuel x 1.15 + 41 + holding + 8

You will not always be carrying holding, but if you are you will be told what it is.
You may be given the flight fuel or you may have to work it out.

Bob

Gotcha Thank you so much