To: Robert357
I can only find one unclear picture of the rudder itself. I cannot tell if there is damage of not. Carbon composites have a very little yield range (they hold or they don't). The eyewitness accounts say parts of the plane flew back and hit rudder section. The information on the other threads now leads me to believe that it was a compressor surge or a series of surges from one engine. When it finally popped hard enough, it blew a flap section off which should still have been in a 15 degree down mode after take off. As a result of the uneven lift caused a pitch change, the computer control would have whipped the rudder to a hard over to correct. The NTSB site indicates that the pilots could not hold the plane level with full aileron command (another indication for loss of a flap panel which have a far greater effective area than the aileron). The blow would not have been great as the joints were already at maximum stress. The actuators or hinge pins could have let go, allowing the rudder to free float back to center position (some rudder systems have actuators with a relief valves built in that permits an override in case of one actuator seizes). The result would be that plane now goes sideways and full force of the airspeed takes the stabilizer off. Without the rudder to compensate for the uneven flight surfaces, the plane augers in as eyewitness and flight data indicate.
Many planes have been flown home without rudders or stabilizers. The loss the rudder alone would not have doomed the aircraft as engine thrust can be used to steer the aircraft. The loss of a flap panel while in the flap down mode would the plane in a spin that very few can recover from. The DC10 in Chicago augered in due to the lost of the hydraulics, not the engine falling off. The failure of pylon took out the hydraulic lines running down the front of the wing which allowed the slats to retract on the one wing while the other remained deployed. The engine lost did not doom it, the uneven flight surfaces did.
To: Traction
Sounds very plausable and consistent with information I have read. The NTSB should be able to spot wing wreckage that shows the condition of the flap control surface and the location of them (i.e. one should be missing, but possibly found in the water near where the tail was found.) One concern I have read is that the black box recorder stopped prior to the final crash, indicating massive electrical/control wire failure in the tail area, ideally, the black box should record flap, rudder, engine inputs, etc. Also there should be some damage on the rudder from the flap surface unless the computer control rudder compensation was suficient to snap the rudder off. Under your scenario, there should be enough physical evidence that NTSB should be able to reach a quick conclusion.
Based on past air traffic travel around Thanksgiving, if the case is open and shut, NTSB should be under extreme pressure to make an announcement that will cause folks to relax and use airplanes for Travel by the Wednesday morning. If they don't, I will assume it is not open and shut and there is something less obvious that required detailed lab analysis.
To: Traction
An intersting new threat based on an aviation week article has been posted. It implies that the autopilot might have been mis-wired and that an unstable rudder oscilation may have caused the tail to fail. It is found at
http://www.FreeRepublic.com/focus/fr/577260/posts
My thoughts are that while, I doubt that the plane was in autopilot that quickly on takeoff, such a problem with the Airbus frame could have produced sufficient cyclic loadings to really fatigue the metal and composite parts within the stabilizer and rudder section of the aircraft. After enough fatique loadings and propagation of small cracks, the wake turbulence, and other takeoff forces could have propagated the crack propagation to the point of complete tail failure that occur.
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