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Old 21st Aug 2010, 16:13
  #1960 (permalink)  
henra
 
Join Date: May 2010
Location: PLanet Earth
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HazelNuts:
The terminal velocity for cw=1 is 189 kCAS at sealevel
Hmmm, what area did you take for that calculation ?
I took Wing area 362m^2
Fuselage 55m x 5,64m.
Weight 210t
=> I get 140 kts
Or do you have real data ?

Regarding the other numbers:
I was just referring to the forward speed vector. I assumed the forward component was just 50 kts upon impact, just a wild guess based on BEA's description of the liekly impact attitude.
For the pure horizontal deceleration that would be OK, but not for the overall energy state.
Regarding overall energy loss, you are absolutely right: I should have considered the vertical component as well. So the overall energy loss was rather equivalent to 43000 ft than to 45000 ft. Equivalent speed would be 980 kts then.
Thanks for that correction !

Doesn't change the overall picture, though.
This wasn't meant as a scientific analysis, rather a rough calculation, to get an idea about the general proportions

Last edited by henra; 21st Aug 2010 at 17:13.
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