Welcome to the CPL Performance question and answer forum. Please feel free to post your questions but more importantly also suggest answers for your forum colleagues. Bob himself or one of the other tutors will get to your question as soon as we can.
dtrembath replied the topic: Re: Echo
Thanks for the reply ...
Calculating the Flight Fuel is not a problem .... the way Bob does it is the correct mathematical approach anyway ... you other example has significant flaws in it ...
So, if they mention a charter flight AND no mention is made of 15% reserve AND no mention made of fixed reserve fuel rate then I can assume the 15% IS included at the cruise rate. Remembering that CAAP 234-1(1) is only advisory.
Ellzy has given an excellent answer to your question already so there's nothing really to add. Thanks Ellzy for passing on your recent experience with the exam. That's a big help for those about to sit.
As to David's questions:
The exam question will make it clear that it is a charter or private flight and you will then include or exclude the 15% reserve respectively. In real life though, most of us would probably include a 15% variable reserve all the time regardless - even though the CAAP doesn't say we really need one. Like that old saying that Bob quoted: "The only time you can have too much fuel is when you are on fire".
For the beta test written answers, I'll doublecheck but I think the answers for fuel required had a tolerance of +/- 0.5 meaning you could put the exact amount in or round to the nearest litre. In the exam though, it will be all multi-choice and the answers options will be more than 1 litre apart.
Take note of what Bob said about the answer "being closest to...". That's the key.
Again, this is all just exam technique. In real life, your company or flying school fuel policy will guide you e.g. round up to the next 5 litres.
Good luck with your exam mate. Fingers crossed! Not long now
Have been looking forward to doing the Performance exam on Thursday ... but have been quite unwell the last few days (cold and chest infections stuff) ... even transferred the exam from Tuesday to Thursday (only option unless I went well into January) ...
OK, think about what the variable reserve is there for: it's a buffer for you to burn during the flight. You shouldn't be surprised if you use it up e.g. due headwinds etc.
It is 15% of your flight fuel and your flight fuel is planned at cruise so therefore the variable reserve will be at cruise as well. But, you don't have to worry about the rate used for the variable reserve though. It's simply 15% of the fuel quantity you already calculated.
Fixed reserves and holding allowances are different though.
Obviously holding reserves will be at some holding rate which must be specified by the examiner.
The fixed reserve is for unexpected circumstances e.g. a blocked runway. No one is going to hold at cruise power waiting for the runway to be cleared. So, the fixed reserve can logically be planned at holding rate. However, some fuel policies will specify that it is to be planned at cruise rates for the extra safety margin. Therefore, the examiner will have to specify what rate is used for the fixed reserve.