Atpl Flight planning - question/help.
 

Hi guys,

could someone help me out on this question, I am pretty sure it is relatively simple and I am doing something stupid. I don't have the workings for the answer as this was from a mock online exam. None of the questions/examples have this format in my text book.

The flight plan can be found here:
http://media.aspeqexams.com/ATPL_Fli...ta_Booklet.pdf

Industrial action is expected around your scheduled ETA. As a precaution you decide to load sufficient fuel to arrive at LAX with an extra 4,000 kg. What is your total ramp fuel requirement?

My answer came out as 109,989kg

Extra fuel= 4000/1000 x (104258-103851)
= 4 x 407
=1628kg penalty if increasing by 4000kg

New total ramp fuel = 4000kg + 1628kg (penalty)+ 510 (taxi) + 103851 (TTL END) = 109 989kg.

Correct answer stated is = 108 183kg

Any help would be appreciated.

Cheers

Well, a few things don't make sense. 1628kg penalty to carry an extra 4000kg of fuel is huge. On the other hand their answer is less that TTL END + 4000 + 510 which doesn't make sense either.

True, maybe its a glitch in there system? because I did notice when I correctly answered a question it came up as wrong, showing me I didn't answer it. Thanks for help anyways mate.

Is it something to do with there already being 2073kg of XTR HOLD KLAX included in TTL END? So you're not adding a full extra 4000kg, but only 1927kg to bring it up to 4000kg total?

I thought that was it to, however adding 1927 +510 + 784 (penalty) + 103 851 (TTL END) = 107072 kg

To check your answer - just replan the whole flight with an extra 4000kg load and count that as fuel, aircraft doesn't care if you're carrying bags or fuel (until you try to burn it!)

If your (careful and correct) plan including 4000kg is significantly different from your fudge factors, I'd be questioning the fudge factors.

How is that penalty being worked out? a 40% penalty seems a bit on the high side?

The answer lies in where it says arriving in lax with 4000kg. Additionally not only is total fuel ie 407kg/1000kg but you also need to calculate burn off in carrying extra fuel which in this case is 384kg/1000kg. By the way it isnt 40% extra its 384kg burn off or 407kg total fuel extra over the total distance from akl to lax. Im on road at moment but pretty sure I arrived at the answer casa has in my head based on the above and adding 4000kg to landing weight. Good luck