mm43 I believe the a/c was in Aternate Law almost immediately, and #II at that. RTLU is auto at reversion, and will not release more sweep until Flaps/slats aiui. It also is not possible to reacquire Normal Law until landing and re program. A complete failure of all tail components is entertained at impact. Consider the Crew Rest capsule. (treated below) If sufficiently left un snubbed by hydraulics, Rudder flutter could happen at almost any speed above the Stall. The definition of flutter would be strained at lower speeds, consider for now that the Rudder "vibrated" rapidly from max. aero pressure then back again.
JD-EE The "tail breaking just aft of the cabin's end, leaving intact the pressure vessel". The vessel is quite strong in resisting higher pressure inside. Failure would involve failing the longerons in tension, and the skin in shear combination tension. The aft bulkhead is a threat in reversal of pressure, as the vessel is not necessarily purposely considered in collapse. It is a stout "plug" if subjected to positive outside pressure, or a combination with aerodynamic and high outside pressure. It is difficult to consider the tail being thoroughly corrupted, and the Aft bulkhead remaining integral to the Fuse.
OE In the salt water long enough to muddy the fracture, a clean break is certainly possible, but perhaps not conclusively demonstrable. Follow me here. For the tip of the Arm to break in its intended fashion is to imply a specific stress path. This path is more indicative of vibrational or fatigue loss, rather than fracture, to wit: Vertical load imparts a tension on the Arm via a "pull" from the Hinge tower. this enters the Bolt, which must then push on the tip. Some dimensional leeway is assumed prior to fracture, yet again, the seal/resin, seat of the bolt on the Spar side appears ignorant of great stress. The Bolt would be the architect of tip fracture, but as I say, there doesn't appear to be any evidence of "movement". Hence the vibration or corrosion/fatigue model would apply. (subject to metallurgy and much closer inspection.) Your statement that you see evidence of lateral movement damage is what I claimed earlier, when criticizing the "Lateral rods".
HazelNuts39 I don't know the A400m, but notice a shift in thinking relative to the VS. There are 4 pair of Brackets, eight clevis pins. Take note of the "Eyes" at the bracket tops. Pair 1 and Pair 4 have much thicker eyes than the two center hold downs/brackets. .....447 impact: I think I see the exchange of energy now as a continuum, though certainly happening at rapid speed. I also think that the Horizontal velocity was kept alive until the nose dropped beneath the waves, making the Horizontal component more energetic than if a nose sub is not taken into account.
Crew Rest
I have looked at great length at the crew rest capsule. From a theory of tail, midsection, nose entry, I think I can hazard an opinion of what happened in the hold. The capsule appears to have an envelope of laminated skins of Aluminum. My guess would be two laminae, with a powerful adhesive joint to make a strong ratio of strength to weight. (The adhesive has the characteristic color of a phenolic resin, but that remains open.) The damage to this skin is more involved than simply being crushed between the Belly and the Cabin floor as the Fuselage flattened on to the surface of the Ocean. The Rest, if enclosed at impact, we may have three separate compression/decompression cycles. first, the Hold flattens out, reducing the volume of its structure, and pressurizes the rest capsule to some value higher than ambient Hold in Fall. The capsule may have held for a short time (even if not "pressurized").
As the Cabin floor comes crashing down on the hold and its contents, the capsule is overpressured, and expands (perhaps even explosively). The damage to the skin of the capsule is certainly rip/tear, but the damage also shows, via the delamination of the skin, that there was an explosion of some great force. Not at all a chemical or other type of explosion, but similar to a scuba tank or pressure cooker failure. Very energetic.
henra If horizontal speed was maintained, perhaps in a skimming reaction, the nose dropping into the water would create a substantially larger acceleration to the VS than previously entertained? Perhaps approaching the 66g?
bear
Last edited by bearfoil; 6th Sep 2010 at 00:09.