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Old 22nd Feb 2021, 05:12
  #112 (permalink)  
fdr
 
Join Date: Jun 2001
Location: 3rd Rock, #29B
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Originally Posted by MLHeliwrench
is that an ‘exit wound’ at three o’clock (from this view) lined up with the ‘entry wound’ at the wing root!


probably not. The blade components do not look like they have punctured any of the remaining structure of the acoustic liner and did not look like they penetrated the ballistic wrap. The blade failure will be interesting to look at in-depth, but I would expect that the missing blade immediately in front of the partial blade failed near the blade root, and as it has departed the fix, has impacted the following blade and torn the LE, leading to it liberating the outer 1/3rd of that blade. The liberated blade is under radial acceleration to the point of release, and aerodynamic bound vortex flow giving lift, so is going to come out at a rate and forward. The full blade looks like it is what went into the #2 pack fairing, and the area around the fuel drip drains aft of that point. 90.4% is 3255 RPM... D=112"; so at climb thrust, it's going to be a bit higher than that, and that is a fair old radial acceleration. Wouldn't be surprised if the full blade that is missing never punctured the cowling, and departed out front and then back to hit the pack. An engine failure & pack failure was on the cards, but, at least the failure didn't look like an impact on the #1 engine. (in LAX, that occurred via a ricochet of a fragmented and liberated disk, but it is not going to happen airborne unless you really have not been living cleanly)

(the white bit at 3 OClock is the fill layer, outside of the ballistic wrap, and it looks like it has flopped forward. It extends forward further than it would with the nacelle annulus... the detail inspection will show what it did better than this musing).

Last edited by fdr; 22nd Feb 2021 at 05:26.
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