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How to identify the accurate intersection of ECHO loading chart forward limit？
Star Alliance created the topic: How to identify the accurate intersection of ECHO loading chart forward limit？
As you all know, some questions ask us to add ballast to make ECHO back into the forward limit.
However, the line you draw crosses the boundary line of envelope (whick is very thick!) in a poor distinct way. I even can not find the intersection, because two lines almost overlap with each other for nearly 1 cm! But even a few mm can make so much difference!
Can some one help? How to identify the accurate intersection of ECHO loading chart forward limit？I even never make one this question correct……
bobtait replied the topic: How to identify the accurate intersection of ECHO loading chart forward limit？
I agree that is a problem. Now that CASA have introduced 'type in' answers it is more of a problem. Surely CASA should accept the limitations of the chart. It was never intended to give exact numerical answers. CASA wont reveal how much margin is allowed. For the sake of the exam, it may help to use the chart to get a 'rough estimate' of the ballast required and then, using the forward limit formula, compare that CofG position with the calculated forward limit. They should be the same. You can then try it again with another ballast value and try to get as close as possible to the recalculated forward limit. That is nothing like what the designer of the envelope intended.