Vertical stabilizers in aluminum and composite fiber

Submitted by Jeff Buster on Mon, 06/15/2009 - 15:45.
Vertical stabilizers in aluminum and composite fiber

The recent crash of the Air France flight 447 Airbus A330-203 left the rudder, and "tail", or vertical stabilizer intact, but separated from the fuselage.   The ruddder and vertical stabilizer floated for a week in the Atlantic off Brazil and were picked up by the Brazilian navy. You can see from the photo in the last link that the rudder  and vertical stabilizer separated fairly cleanly at the location where the rudder had joined with the hull of the aircraft.
Much of the recovered floating tail component is made of composites – fiber and resin materials – including the bolts which attached the rudder/stabilizer to the hull of the aircraft. James Ridgeway on Counterpunch.org reports that in 2001 American Airlines flight 587, also an Airbus 330, had its tail ripped off in air turbulence.
Two tails torn off is too many and raises the urgent question: has the testing of the composites been adequate and/or are the composites failing from fatigue or other deterioration?
Composites have been around for a half century, but only recently have they begun to be used in critical “heavy lifting” areas of commercial aircraft. 
Do we know what we are doing with these composites? 
How do they react to lightening?   How do they react to the sub zero temperatures at 35,000 feet? How do they react to UV over the years? How do they react to vibration and load cycling? How do layers of composites react/delaminate in vacuum/pressure cycling?
Testing the integrity of composites – particularly when they are combined in a hybrid with metals – is not easy as this article describes - tap testing and vacuum/pressure testing.  
The FAA should order an immediate inspection and integrity testing of the rudder/vertical stabilizer connection to the fuselage of all Airbus 330-200 jets to determine if there is any common failure mode – or if the two jets which have crashed because of tail failures did so because the airplane stressed the tail beyond its designed structural strength.
 
I don't like the looks of tails floating....

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Air France flight recorder found - tail failure theory...

Submitted by Jeff Buster on Sun, 07/17/2011 - 21:58.

 It appears that the tail was not the problem with the flight failure.   The pitot tube looks like the culprit.  And the pilots thought the plane was going too slow, and didn't believe the other instruments  re altitude, so they headed the plane up at an angle which resulted in stall, and the plane fell into the Atlantic intact.  

Amazing that the French searched for over a year for the recorders in the deep Atlantic...and found them.

Here is a web report about the fatale flight PRIOR to the recorders being found... lots of variables involved