Center of Gravity
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Joined: Aug 2019
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From: Oman
I would like to know for take off we calculate two CGs basically all speeds settings are decided on Take off CG . The zero Fuel CG is also calculated
What is the purpose of Calculating the Zero Fuel CG
Can any one can educate me
What is the purpose of Calculating the Zero Fuel CG
Can any one can educate me
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Joined: Oct 1999
Posts: 802
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From: Chicago, IL
What airplane type?
Some aircraft with swept wings can encounter an change in CG as fuel is burned. Obviously the ZFW CG is not helpful but there will be a forward most CG location encountered at ZFW + XXXlbs of fuel remaining. IOW you are determining that the CG remains inside the aircraft operating envelope while airborne.
Some aircraft with swept wings can encounter an change in CG as fuel is burned. Obviously the ZFW CG is not helpful but there will be a forward most CG location encountered at ZFW + XXXlbs of fuel remaining. IOW you are determining that the CG remains inside the aircraft operating envelope while airborne.

Joined: Dec 2005
Aviation Qualifications: ATPL
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From: Hong Kong
Because it has to be within CG limits for all possible situations. So in the worst case scenario where you blow through all your reserve fuel, at least it'll fly. Or glide.
Joined: Feb 2017
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From: Europe
If you are zero fuel you still need to be properly balanced to glide safely, recover from stall, etc.
So, this metric checks whether on zero fuel you are still within the CG envelope and not out of whack.
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Joined: Feb 2000
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From: UK
In light aeroplanes, almost always there's a straight line of CG versus weight in any given configuration.
In airliners, and even more so with military aeroplanes, it's a lot more complex. I used to work with a military aircraft that had a 19 tank system, emptying on an automatic schedule - be thankful it's as simple as it is in light aircraft!
G
In airliners, and even more so with military aeroplanes, it's a lot more complex. I used to work with a military aircraft that had a 19 tank system, emptying on an automatic schedule - be thankful it's as simple as it is in light aircraft!
G





