Originally Posted by
B-HKD
About 41-42% MAC. The aft limit being 33% MAC.
The Korean -400F with the loadsheet error, landed with 40.2% MAC.
Interesting!
Just out of curiosity I was tempted to do some rough guestimates/calcs.
Don't shoot me for it this is not meant to speculate on the cause, just checking some plausibilities and orders of magnitude.
So let's have a look:
Mean aerodynamic chord of the 747 is 327,8 inches. (
http://www.boeing.com/assets/pdf/com...misc/A20WE.pdf).
7% of that would mean 22,95 inches. (Korean managed to take off with ~38% so let's assume KAL + 2% for a likely unrecoverable config for takeoff).
So the Cg of the aircraft would have to be ~23 inches behind the aft Limit in a case where the front wheel almost lifts off the ground.
If we assume a TOW of roundabout 300.000kg an MRAP weight of ~12000kg a single MRAP would havce to shift a whopping 573 inches to get that sort of Cg shift.
If we instead assume they added 25.000 kg of fuel that would require the added fuel to be stored ~275 inches behind aft Cg to achieve the same shift.
Question to the 747 experts: Is that technically possible?
Anyway These rough calcs give me the Feeling there is really a massive load shift required to get into a seriously tail heavy config. And the KAL was still able to land safely.
The more one looks into it the more puzzling it gets.