RE seatbelts, bodies, etc:
I've tried to choose my words carefully, as descriptions regarding this subject can be distressing. If you may be offended by such things, please don't read this post.
- The range of g-force presumed at impact (by most) for this occurrence is greater than the force the seats are manufactured and certified for (which can generally be described as "16G" but is a little more complicated than that seemingly simple figure).
- In failures of this (presumed and postulated) type of impact (high vertical component, low forward component) there can be some fairly common failure characteristics. One of these -- which I have seen myself many times -- includes the failure or separation of the seat to seat-back attachments. So the two portions become separate pieces, or if still joined, it is a broken and "floppy" join, in which case the seats are often found in an open or "reclined" postion. In either case, even without stuctural compression or failure of the seat mounting itself -- the "legs" so to speak -- it is sometimes very easy for a body to be released (by recovery personnel) or to slide out if in water, without unfastening what was once a snug belt.
- IMHO the notion that many of the recovered bodies were "unseated" at impact is in clear contradiction to the described injury patterns. For someone not seated, the predominant injuries would certainly not be the pelvic and spinal patterns described. One can't have it both ways. If the BEA injury summaries and comments are correct, then the "forty some odd" people exhibiting those traits were seated.
I don't mind engaging in further discussion of these points via PM but, due to the inherently nasty nature of getting more specific, I'm not prepared to do so on an open forum.
grizz