here is something to chew on, i'd say take it with a pinch of salt.
for me personally i like Boeing warey of airbus, but that may be just were my lack of experiance lies. they are different and have different logic but do have some neat ideas even if not all of them work.
ian
Subject: Air France Accident: Smoking Gun Found
A Brazilian Naval unit reportedly found the complete vertical fin/rudder assembly of the doomed aircraft floating some 30 miles from the main debris field. The search for the flight recorders goes on, but given the failure history of the vertical fins on A300-series aircraft, an analysis of its structure at the point of failure will likely yield the primary cause factor in the breakup of the aircraft, with the flight recorder data (if found) providing only secondary contributing phenomena.
The fin-failure-leading-to-breakup sequence is strongly suggested in the attached (below) narrative report by George Larson, Editor emeritus of Smithsonian Air & Space Magazine.
It's regrettable that these aircraft are permitted to continue in routine flight operations with this known structural defect. It appears that safety finishes last within Airbus Industries, behind national pride and economics. Hopefully, this accident will force the issue to be addressed, requiring at a minimum restricted operations of selected platforms, and grounding of some high-time aircraft until a re-engineered (strengthened) vertical fin/rudder attachment structure can be incorporated.
Les
--------------------------(George Larson's Report)---------------------
This is an account of a discussion I had recently with a maintenance professional
who salvages airliner airframes for a living. He has been at it for a while, dba BMI
Salvage at Opa Locka Airport in Florida. In the process of stripping parts, he sees
things few others are able to see. His observations confirm prior assessments of
Airbus structural deficiencies within our flight test and aero structures communities
by those who have seen the closely held reports of A3XX-series vertical fin failures.
His observations:
"I have scrapped just about every type of transport aircraft from A-310,
A-320, B-747, 727, 737, 707, DC-3, 4, 6, 7, 8, 9, 10, MD-80, L-188, L1011
and various Martin, Convair and KC-97 aircraft.
Over a hundred of them.
Airbus products are the flimsiest and most poorly designed as far as
airframe structure is concerned by an almost obsession to utilize composite
materials.
I have one A310 vertical fin on the premises from a demonstration I just
performed. It was pathetic to see the composite structure shatter as it did,
something a Boeing product will not do.
The vertical fin along with the composite hinges on rudder and elevators is
the worst example of structural use of composites I have ever seen and I am
not surprised by the current pictures of rescue crews recovering the
complete Vertical fin and rudder assembly at some distance from the crash
site.
The Airbus line has a history of both multiple rudder losses and a vertical
fin and rudder separation from the airframe as was the case in NY with AA.
As an old non-radar equipped DC4 pilot who flew through many a thunderstorm
in Africa along the equator, I am quite familiar with their ferocity. It is not
difficult to understand how such a storm might have stressed an aircraft
structure to failure at its weakest point, and especially so in the presence of
instrumentation problems.
I replied with this:
"I'm watching very carefully the orchestration of the inquiry by French
officials and Airbus. I think I can smell a concerted effort to steer
discussion away from structural issues and onto sensors, etc. Now Air
France, at the behest of their pilots' union, is replacing all the air data
sensors on the Airbus fleet, which creates a distraction and shifts the
media's focus away from the real problem.
It's difficult to delve into the structural issue without wading into the
Boeing vs. Airbus swamp, where any observation is instantly tainted by its
origin. Americans noting any Airbus structural issues (A380 early failure
of wing in static test; loss of vertical surfaces in Canadian fleet prior to
AA A300, e.g.) will be attacked by the other side as partisan, biased, etc. "
His follow-up:
One gets a really unique insight into structural issues when one has
first-hand experience in the dismantling process.
I am an A&P, FEJ and an ATP with 7000 flight hours and I was absolutely
stunned, flabbergasted when I realized that the majority of internal
airframe structural supports on the A 310 which appear to be aluminum are
actually rolled composite material with aluminum rod ends. They shattered.
Three years ago we had a storm come through, with gusts up to 60-70 kts.,
catching several A320s tied down on the line, out in the open.
The A320 elevators and rudder hinges whose actuators had been
removed shattered and the rudder and elevators came off.
Upon closer inspection I realized that not only were the rear spars
composite but so were the hinges. While Boeing also uses composite
material in its airfoil structures, the actual attach fittings for the elevators,
rudder, vertical and horizontal stabilizers are all of machined aluminum."
-----------------(end of narrative)---------------
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Originally Posted by V8Ian
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