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Old 13th Sep 2008, 16:31
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FRQ Charlie Bravo
 
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Dead weight fuel and the CASA ATPL Information Booklet

Here's a curly one I found in my old uni notes:

Flight from Alpha to Charlie with an intermediate stop at Bravo where there is no fuel. Consider only Normal Ops.

Flight fuel A to B 5200 kg
Flight Fuel B to C 4200 kg

Alpha and Bravo are suitable but Charlie is Acceptable and Suitable with INTER

Using Fleet Basic Weight what is max payload out of Alpha?

The answer involved calculating the FF, Reserves, Holding and Taxi. What threw me was the calculation of 10% CR for sector 1. Surely the FF for sector 2 covers that. I understand that a company would be pretty pissed off to have the sector 2 fuel used unexpectedly on sector one but if it's a question of Max Payload / Min Fuel then I would argue that the answer in my book is not min fuel.

For those playing at home the answer was that it was Landing Weight limited at Bravo.

There is one sentence at the end which reads "Assume contingency reserve is consumed but fixed reserve intact for the purpose of flight planning" but I find that a bit misleading. Surely I could understand being told to err on the side of caution and consider the CRs as cumulative but that's not what I'm told. Based on that the sentence that I ought to consider the CR as consumed I expect to be able to use every KG of 1st sector CR as payload (since I'll burn it off before landing thereby meeting but not exceeding my MLW).

If you come across this in a CASA exam then please share. It is my understanding that CRs (like holding fuel) are not cumulative (but commercial considerations such as not wanting to be stranded in Woop Woop may dictate otherwise... but this is a CASA exam).

FRQ CB

PS Tiger19 with regards to our conversation earlier about the use of only the first portion of a return trip of multiple sectors/forecast areas page 6-2 of my Aviation Theory Centre book pointed out the guide to data extraction given in the ATPL Information Booklet. From there I found out why the texts we have always gave SGRs based on only the early sector WX and Fuel Flow. Para 3.4.2 states that it it the Temp at the point of failure which should be used (and by extension of this logic find the conditions for your SGR calculation).

Last edited by FRQ Charlie Bravo; 13th Sep 2008 at 16:33. Reason: Opinions are like belly buttons... so I replaced the word
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