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Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 1:54 am

For almost five years, one of the world's largest jetmakers knew that the 27-foot-tall tail fin on one of its jets had almost snapped off in flight.

Officials with manufacturer Airbus understood that losing a tail fin would prove catastrophic. Even so, they kept their concerns to themselves until after a tail fin did break off one of its jets, causing the second-worst aviation disaster in U.S. history.

Not until after American Airlines Flight 587 crashed in 2001 -- a catastrophe investigators say was caused when the tail fin broke off the A300 jet -- did Airbus disclose its findings from an incident in 1997 to government safety officials, a USA TODAY investigation has found.

Had federal regulators known earlier how easily tail fins could break in flight, the crash of Flight 587 -- and the deaths of 265 people -- might have been prevented, according to some accident investigators and aviation safety experts. The jet crashed Nov. 12, 2001, just after takeoff from New York's John F. Kennedy International Airport.

The nation's aviation safety system is designed to prevent crashes by learning lessons from close calls. In this case, the system broke down.

''When I heard (about what Airbus knew), it made me sick,'' says Bernard Loeb, who headed the National Transportation Safety Board (news - web sites)'s (NTSB (news - web sites)) aviation division until January 2001. ''People are kicking themselves.''

The system is dependent on airlines and jetmakers sharing their knowledge and experience with federal regulators. The NTSB, an agency with limited resources, cannot function without this help, current and former investigators agree. But those are the very entities the NTSB investigates.

Airbus officials say they did nothing wrong. They say that the crash of Flight 587 was due to mistakes by the pilots and that there is nothing they could have done to prevent it. Attempts to find fault with the company are ''projected wisdom in hindsight,'' spokesman Clay McConnell says.

USA TODAY reviewed hundreds of pages of NTSB documents and interviewed more than a dozen government officials and knowledgeable sources. The review found that on May 12, 1997, American Airlines pilots on Flight 903 from Boston to Miami lost control of the jet. In response, they made a series of radical maneuvers that placed extreme stress on the tail fin, nearly snapping it off. Eventually, they landed safely.

Within days, federal investigators knew that the jet had nearly crashed, but they did not realize how close it came to breaking apart in midair. Then last year, a closer examination of the tail revealed that it had cracked during the incident. If federal regulators had known this information, they say, they could have warned pilots to avoid the nearly identical maneuvers that caused the crash two years ago.

It's impossible to know for certain whether a more thorough investigation in 1997 could have prevented the 2001 crash, several senior investigators say. Those officials still do not know why the co-pilot aboard Flight 587, leaving New York for the Dominican Republic, suddenly began his maneuvers. A final report on the accident is expected early next year.

Even so, said NTSB board member Carol Carmody, ''It's enormously frustrating that we didn't have this information.''

Carmody was acting chairwoman of the agency when Airbus revealed its findings last fall. ''I feel that we missed an opportunity,'' she said in an interview.

The stakes are also enormous in lawsuits stemming from the 2001 crash. Airbus and American Airlines are battling over who should pay damages for the crash.

The close call

Flight 903 from Boston had been routine, if a little bumpy. The pilots, waiting for storms over Miami to clear, reminded passengers to buckle their seatbelts. Controllers ordered them to hold at 16,000 feet near West Palm Beach.

At 3:29:14 p.m. May 12, 1997, as the jet began a turn, it suddenly banked hard to the right, back to the left, then to the right again.

''It was horrifying,'' Michelle Singh, 36, who was seated in row 16, recalled in an interview. ''There were no words to explain. People crying. People hurt. People scared. I was ready to die.''

Passengers clung to each other as the gyrations tossed them from side to side. Anything not strapped down -- shoes, briefcases and passengers themselves -- flew about the cabin, according to NTSB records. After 12 seconds, the jet began to plunge. It fell 3,000 feet in 18 seconds. Melanie Joison's baby flew out of her arms. Joison unbuckled her belt to grab her baby and crashed face-first into the ceiling. The blow knocked her unconscious and broke four of her ribs. Other passengers safely caught the baby.

''The terror and the screams were more than I have ever experienced,'' Scott Stow, an American pilot sitting in the passenger section, told investigators then.

Capt. Mark Eberle and co-pilot Donald Rescigno told investigators it seemed that a mysterious force -- perhaps a powerful downdraft -- had blown the jet out of control.

Initially, the jet banked 56 degrees to the right -- twice as steep as a passenger jet ever gets in a normal flight. The co-pilot tried to level the jet with the control wheel, which activates panels on the wings. It had no effect.

Rescigno tried the rudder, a large vertical panel at the rear of the tail fin. His left foot stomped on one of two pedals that move the panel. The rudder swung left.

A jet's rudder has tremendous power. It keeps the jet flying straight if one of the two engines fails. The control wheel, which looks similar to a car's steering wheel, is the preferred way to level a jet's wings, but the rudder accomplishes the same thing in a clumsy, overpowering way.

Rescigno held the rudder pedal down for four seconds. By then, the jet was rolling back to the left so quickly he could not control it. The left wing dropped sharply. Rescigno responded by slamming on the right rudder pedal, which began the cycle again. The jet banked back to the right even more steeply, to 65 degrees.

Overall, the jet banked left or right nine times within 40 seconds. In the most severe bank, the jet tilted at 83 degrees -- its right wing pointed nearly at the ground.

Eventually, the pilots increased the speed of the jet enough to regain control. Thirty minutes later, the jet landed in Miami, the cabin a mess of upended food carts, luggage and trembling passengers.

The pilots' rudder movements were nearly identical to those on Flight 587. The co-pilot on the later flight whipped the jet's rudder left or right five times.

On its last swing, the tail fin snapped off the fuselage.

Pilots caused 'stall'

Soon after Flight 903, NTSB investigators discovered that the incident had little to do with a gust of wind. The pilots had made a series of errors that caused the wild ride.

The pilots allowed the jet to slow too much as it entered the holding pattern, the jet's data recorder showed. The pilots apparently put the engines in idle as they descended and neglected to add power after leveling off at 16,000 feet. As a result, the jet essentially stopped flying, a condition known as a ''stall.'' When the pilots began the initial bank to the right, the stall caused the right wing to drop more than the pilots intended.

The discovery that pilots could forget to maintain enough speed disturbed the NTSB. The agency focused on that failing as the central problem.

A yearlong probe began.

Federal investigators had no idea that within a month of the incident, Airbus engineers in Europe found an additional problem: The jet's gyrations had put massive strain on the tail fin.

In an internal memo on June 12, 1997, an unidentified Airbus official wrote that his department ''urgently'' recommended additional inspections of the jet because the forces on it had apparently exceeded the ''design limit.'' That meant that the wind and jostling on the tail fin had exceeded the greatest forces it had been expected to experience in its lifetime.

Then, on June 19, a more complete analysis showed that the forces not only had gone above the design limit, they also apparently had reached the ''ultimate limit.''

When engineers build a jet, they compute the greatest forces likely to hit surfaces, such as wings and the tail. These are known as design limits. For a safety margin, international aviation regulations mandate that they make those surfaces 50% stronger. These are the ultimate limits, above which a tail fin or other surface is expected to fail.

It's extremely rare for commercial aircraft to reach a design limit in flight. It's almost unheard of for one to reach an ultimate limit. That would mean it had come dangerously close to breaking apart. Such a finding would get immediate attention from federal investigators -- if they learn about it.

Had Airbus pressed the matter in 1997, its findings would have been worse. Flight 903's tail fin reached or exceeded its ultimate limit three times during the incident, Airbus itself calculated last year. A Federal Aviation Administration (news - web sites) official testified at an NTSB hearing in October that a conservative estimate found the stress on the tail fin went well above the ultimate limit -- to within 1% of the force required to break it off.

In June 1997, Airbus requested that American Airlines perform another inspection of the jet to ensure it was not damaged. American inspectors, following Airbus' instructions, examined the tail fin. But they did not use methods that would have allowed them to see inside the tail fin. They saw no damage from their visual inspection, and the jet continued to fly for nearly five years.

Only last March, as part of the Flight 587 investigation, did Airbus conduct an ultrasound inspection of the tail fin on the jet involved in the 1997 incident. The inspection found two crescent-shaped cracks at one of the points where the tail fin attaches to the fuselage. The fin was replaced. Airbus says the tail fin was still strong enough to meet regulatory requirements.

Airbus engineers weren't the only ones who expressed worries about the incident. A high-ranking American Airlines pilot wrote a memo to a senior official in May 1997 warning that the pilots' use of rudder had nearly caused major structural damage to the jet. Paul Railsback, flight operations managing director, urged immediate changes in American's pilot training, says the memo obtained by USA TODAY.

Again, the NTSB has no record that Railsback's concerns were brought to its attention. American says it altered its training to reflect his comments.

Airbus' response

Airbus officials deny withholding data or hindering the probe of Flight 903. ''I am convinced that my company made a good faith effort to raise these concerns,'' says McConnell, Airbus' spokesman.

Officials also say they did not realize that the tail fin on the jet had nearly broken loose. In part, that's because Airbus built the tail fin 25% stronger than regulations required. By insisting on an additional inspection of the tail, Airbus felt confident that it had not been damaged, McConnell says.

Furthermore, he says, the 1997 assessments were imprecise and Airbus did not calculate the actual stress on the tail until last year. The NTSB and American had access to the same data and failed to raise concerns, he says.

At the NTSB hearing in October on Flight 587, an American Airlines official was permitted to put questions to Airbus officials. With the two firms feuding over who is at fault in the 2001 crash, the questioning quickly grew tense. Airbus' Michel Curbillon said the company had shared its concerns about Flight 903 with federal investigators and others. ''This has been known within the company and was also informed to everybody,'' Curbillon said.

His questioner, American's Tim Ahern, who had worked on the Flight 903 investigation, disputed him. ''Frankly, as a party to that event, sir, this information was just (released) this year,'' Ahern said.

Curbillon pointed to a report submitted to the NTSB in August 1998, on the Flight 903 investigation. Airbus' flight safety director, Yves Benoist, wrote that pilots needed to be trained better on how to use the rudder. ''Using too much rudder in a recovery attempt can lead to structural loads that exceed the design strength of the fin,'' the report said.

Airbus officials say they underscored their concerns in 1997 by raising repeatedly the broader issue of pilot training on rudder use. For example, an August 1997 letter sent to American and written by Airbus, Boeing and the FAA warned that pilots could damage a jet with too much rudder.

But the NTSB has no record that Airbus disclosed what it had learned about the stress put on Flight 903's tail fin. The submission to the NTSB contained only a general warning about rudder use. The letter to American did not mention Flight 903 and was not sent to the NTSB until last year.

NTSB and American officials say the Airbus warnings were so vague that they did not attract attention in the Flight 903 probe.

When Loeb, who has retired from the NTSB, learned in October that Airbus knew in 1997 about the high stress on Flight 903, he was dumbstruck.

He had overseen the earlier investigation and never heard a word about the high stress on the tail fin, he says. Even if the calculations were preliminary, Airbus had a duty to share them, he says.

''That's a significant, significant issue,'' Loeb says. The jet involved in the incident should have been grounded until regulators were certain it was not damaged by the extreme forces, he says.

Officials who were part of the probe in 1997 say if they had known of Airbus' findings and the damage to the fin, it would have changed the focus of the investigation. Rather than focusing on the pilots' actions, the NTSB would have looked more closely at the rudder itself, they say. ''I think the answer is most assuredly we would have done something more on 903 if we had known this, if we had heard this from Airbus,'' the NTSB's Carmody says.

What about safety board?

Among the small circle of senior accident investigators, there is also debate about whether the NTSB itself should have seen the clues back in 1997 that rudder use could damage a tail fin.

According to former NTSB chairman James Burnett, the answer is yes. The agency's job is to turn the jumble of aviation incidents into nuggets of common sense that prevent accidents. By definition, it should have unraveled the puzzle and acted, Burnett says.

But, with only 60 aviation accident investigators and engineers to work cases involving airlines, it does not surprise him that the NTSB occasionally misses things. This is especially true during busy periods such as 1997, when the board was occupied with two crashes that had occurred the prior year: TWA Flight 800 and the ValuJet crash in the Florida Everglades. ''But it should be an occasion for taking stock,'' Burnett says.

Such concerns are not new. A Rand Corp. report in 1999 warned that the agency was too dependent on the airlines and aircraft manufacturers it investigates. The report urged greater use of independent experts to supplement NTSB investigations.

Loeb says he wishes now that, in the midst of perhaps the busiest period in the agency's history, he had spent more time on Flight 903.

''People are saying, 'We should have done more.' But the fact is, these are people who are working 60 hours, 70 hours a week and getting paid for 45 or 50. Yeah, they are going to miss things and feel bad about it,'' he says.

''On the other hand,'' Loeb adds, ''if Airbus did the calculations and didn't bother to tell us, shame on them.''
 
backfire
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 2:03 am

Yeah, yeah...a "USA Today investigation"...how melodramatic...too bad a British TV documentary dredged all this up weeks ago.
 
Ikarus
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 2:17 am

OK, that report is rather sensationalist.... especially the headlines make it sound much worse than the actual omissions & errors seem to have been.

But the report is rather interesting: It highlights the dangers of human reaction time. The stall and pilot induced bank oscillations of Flight 903 were at a frequency similar to that of human reaction time, if I read it correctly, leading to the positive feedback and escalating oscillations.

The second factor - a really really interesting and worrying one, is the "visual inspections" bit. Every aeronautical engineering student is taught in their materials lectures that any composites components mustn't be inspected just visually, because damages are often (in fact, generally) not visible from the outside. When Airbus suggested some inspections, and they only performed visual ones, that suggests a really serious safety issue: Either the inspection guidelines by Airbus (or the FAA or whoever prepares them) were flawed by not specifying that composite components MUST be inspected with UV or x-ray methods, or the inspections carried out were shoddy. Either way, the issue of inspection of composite components stands out more in my mind than speculative back-of-the-envelope-calculations by Airbus engineers that weren't immediately shared with the NTSB. If Airbus engineers did a full analysis, they should have shared their suspicions. If they just did some preliminary educated guesses, then they perhaps should have pursued the avenue of investigation further. They even did that by asking AA to inspect the tailfin. I suppose it boils down to a genuine error, and not a hush-up: After they inspection they must have felt calmed that nothing was wrong (even though it was wrong and they just did not know about it). If the NTSB and Airbus had the same data, then they are both equally to blame for not recognizing the threat, but in all honesty, with hindsight everything is so much easier to say, so I don't think either of them deserves any blame for not predicting that AA587 could happen.

But who is to blame for the purely visual inspection of components that usually suffer damages internally, without visual clues? That would interest me much more! And, even more importantly, what are the guidelines today - for the A300 as well as more modern airliners?

Regards

Ikarus
 
teva
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 2:31 am

Ikarus, thanks for your info regarding how to conduct an inspection on composite.
Another reason that has made airbus overconfident is their recommandation on AA pilots training on the use of the rudder.
If pilots are trained on the limits of the use of the rudder on a plane, the plane has been certified for those limits, and nothing should happen.
If you don't respect the limits, mthen, you will have consequences.
But it is true for other aspect of our industry.
you load too much weight on your plane, or you don't respesct the loading instruction, and you will end with an incident (such as autorotation) or an accident (the fine air crash)
In this case, and from what I understand, Airbus did basic calculations, (not detailed and precise ones), asked AA to inspect to make sure it was OK, and then concluded there was no nee to go deeper in the calculation, because AA would modify their trainig, and pilots would not overcome the limits.
And as Ikarus sai, everyone had the same info, (NTSB, AA, ...) and had the same overconfidence on this, considering it was a non issue.
Teva
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N79969
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 2:35 am

Although overcontrolling an airplane is generally not a good thing, I think it is peculiar that pilots can actually snap off the tail through rudder use in an otherwise normal flight profile. That has always been a curious aspect for me. If the airplane were anywhere near max speed or in an unusual flight attitude, then it would make more sense. I don't think the pilots of AA 587 should be blamed.
 
b757300
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 3:50 am

I don't think Airbus has ever admitted fault in an accident so why should they start now? Almost every crash of an Airbus has been due to "pilot error". Remind me never to fly any aircraft when the pilot is a current or former 'Bus driver.
"There is no victory at bargain basement prices."
 
777236ER
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 3:55 am

I don't think Airbus has ever admitted fault in an accident so why should they start now? Almost every crash of an Airbus has been due to "pilot error". Remind me never to fly any aircraft when the pilot is a current or former 'Bus driver.

Oh please, Airbus isn't some evil company that denies when it makes mistakes. Remember the botched job Boeing did on the JAL 747SR? How many people died? The Amsterdam El-Al crash? The Alaska MD-80?

Not to mention the 737 rudder hardovers! How did long Boeing say it was nothing more than termals flipping over the 737s?

Boeing isn't a saint.
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Flying-Tiger
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 4:16 am

Ehmmm... if I readthis paragraph correctly it says something completely different:

"Within days, federal investigators knew that the jet had nearly crashed, but they did not realize how close it came to breaking apart in midair. Then last year, a closer examination of the tail revealed that it had cracked during the incident. If federal regulators had known this information, they say, they could have warned pilots to avoid the nearly identical maneuvers that caused the crash two years ago."

I read "federal investigators" and "federal regulators" here, "federal investigators" who knew about this problem within days and who didn´t bother to do some deeper research into this problem - and who apparently didn´t inform the regulators about this either. I don´t see where Airbus is supposed to be at fault, it is a mere fault of the Federal Authorities in this case IMO.

Regards
Flying-Tiger
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STT757
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 4:28 am

What's worse, the Feds not finding the problem or Airbus knowing about it and not saying anything.

"Airbus officials deny withholding data or hindering the probe of Flight 903. ''I am convinced that my company made a good faith effort to raise these concerns,'' says McConnell, Airbus' spokesman.

Officials also say they did not realize that the tail fin on the jet had nearly broken loose. In part, that's because Airbus built the tail fin 25% stronger than regulations required. By insisting on an additional inspection of the tail, Airbus felt confident that it had not been damaged, McConnell says.

Furthermore, he says, the 1997 assessments were imprecise and Airbus did not calculate the actual stress on the tail until last year. The NTSB and American had access to the same data and failed to raise concerns, he says.

At the NTSB hearing in October on Flight 587, an American Airlines official was permitted to put questions to Airbus officials With the two firms feuding over who is at fault in the 2001 crash, the questioning quickly grew tense. Airbus' Michel Curbillon said the company had shared its concerns about Flight 903 with federal investigators and others. ''This has been known within the company and was also informed to everybody,'' Curbillon said.

His questioner, American's Tim Ahern, who had worked on the Flight 903 investigation, disputed him. ''Frankly, as a party to that event, sir, this information was just (released) this year,'' Ahern said.

Curbillon pointed to a report submitted to the NTSB in August 1998, on the Flight 903 investigation. Airbus' flight safety director, Yves Benoist, wrote that pilots needed to be trained better on how to use the rudder. ''Using too much rudder in a recovery attempt can lead to structural loads that exceed the design strength of the fin,'' the report said.

Airbus officials say they underscored their concerns in 1997 by raising repeatedly the broader issue of pilot training on rudder use. For example, an August 1997 letter sent to American and written by Airbus, Boeing and the FAA warned that pilots could damage a jet with too much rudder.

But the NTSB has no record that Airbus disclosed what it had learned about the stress put on Flight 903's tail fin. The submission to the NTSB contained only a general warning about rudder use. The letter to American did not mention Flight 903 and was not sent to the NTSB until last year.

NTSB and American officials say the Airbus warnings were so vague that they did not attract attention in the Flight 903 probe.

When Loeb, who has retired from the NTSB, learned in October that Airbus knew in 1997 about the high stress on Flight 903, he was dumbstruck.

He had overseen the earlier investigation and never heard a word about the high stress on the tail fin, he says. Even if the calculations were preliminary, Airbus had a duty to share them, he says.

''That's a significant, significant issue,'' Loeb says. The jet involved in the incident should have been grounded until regulators were certain it was not damaged by the extreme forces, he says.

Officials who were part of the probe in 1997 say if they had known of Airbus' findings and the damage to the fin, it would have changed the focus of the investigation. Rather than focusing on the pilots' actions, the NTSB would have looked more closely at the rudder itself, they say. ''I think the answer is most assuredly we would have done something more on 903 if we had known this, if we had heard this from Airbus,'' the NTSB's Carmody says."




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EGGD
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 5:01 am

why is it Airbus at fault here? Shouldn't American be at fault as surely they carry out their own maintenence and noticed a crack in the tailfin of one of their aircraft that their pilots had caused?
 
Going64
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 5:08 am

and here we go again B757300; always and always the anti Airbus blablabla without any facts but 'personal 'I hate Airbus so let's spit it out whenever possible'; is it so difficult to provide facts on this forum based on publications etc.? Look at the others in this topic, they come up with proper information!

This topic took quite some time to read and I wanna say I'm very pleased with the level of detail provided. Very interesting and I guess to be continued .....

Peter
 
tekelberry
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 6:58 am

Another reason to never fly Airbus jets unless necessary. They just aren't built the way Boeing jets are.

I am disappointed that AA hasn't planned the A300's retirement yet.

"why is it Airbus at fault here? Shouldn't American be at fault as surely they carry out their own maintenence and noticed a crack in the tailfin of one of their aircraft that their pilots had caused?"

They followed the procedures Airbus had provided them.
 
Staffan
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:02 am

"Another reason to never fly Airbus jets unless necessary. They just aren't built the way Boeing jets are."

What major differences are there in the way the two are constructed?

Staffan
 
tekelberry
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:04 am

"What major differences are there in the way the two are constructed?"

Obviously they are doing something wrong, at least with the A300 since the A300's tail has a hard time staying attached to the airplane.

[Edited 2003-05-28 00:04:29]
 
Staffan
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:07 am

How many times has it happened? Was it due to construction or because inspections weren't what they should have been after the first incident?

Staffan
 
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STT757
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:13 am

"What major differences are there in the way the two are constructed?"

The use of carbon fibers in place of good ole' aluminum, it's much much tougher to detect cracks in the carbon fibers than aluminum.

You have to X-ray (for lack of a better term) the heck out of the carbon fibers to find the cracks.

Eastern had similar problems with the A-300s, finding cracks.
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Staffan
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:22 am

Different materials is going to need to have inspections carried out in different ways, it scares me if people think they are all done the same.

In many cases even aluminium can't be inspected visually, so what's the deal here?

If it's done properly, there should be no problem!

Staffan


[Edited 2003-05-28 00:23:06]
 
Ikarus
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:23 am

Carbon fibres are the way of the future. They're used in ever-increasing amounts in more and more important structural parts, by all manufacturers. Indeed, the 7E7 will, if it is built, probably be more plastic than aluminium. There's nothing wrong with using composites instead of aluminium. What's wrong is if inspection guidelines are insufficient. Or, if in the spirit of pioneering materials, certain things get used before all qualities and all pitfalls are known (eg if they used the carbon fibres and wrote inspection guidelines without being aware of the potential for visually invisible internal damages - note I said IF because I am not aware of enough details to form an opinion)

Regards

Ikarus
 
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STT757
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:25 am

The manufacturers are the ones who set the inspection guidelines, lack of communication from a manufacturer is the basis of the discussion/ argument with regards to AA flight 587 (and 903).
Eastern Air lines flt # 701, EWR-MCO Boeing 757
 
Staffan
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:28 am

Yeah, I was just answering the crackdown on airbus.
I think the article is good food for thought, but none of us here is in much of a position to comment on who is right or who is wrong, based on an article. At least that's what I think.

Staffan
 
m717
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 7:44 am

"I read "federal investigators" and "federal regulators" here, "federal investigators" who knew about this problem within days and who didn't bother to do some deeper research into this problem - and who apparently didn't inform the regulators about this either. I don't see where Airbus is supposed to be at fault, it is a mere fault of the Federal Authorities in this case IMO."

While at first glance, it appears simple to fault the "federal investigators" for not "digging deeper", and assign them the fault here, the facts are that the NTSB is chronically and severely under funded and under staffed. One of the most telling bits of information in that article I'm sure goes virtually unnoticed by anyone (including the readers on this forum) reading that article.

There are only 60 investigators and engineers to work these cases, and these investigators typically work 60-70 hour weeks while getting paid for 45-50. During this time period of this incident, the Safety Board investigators were also busy with TWA 800 and the ValuJet crash. I wouldn't exactly categorize the investigators as "not bothering to dig deeper".

It's all too easy to sit here and criticize and assign fault in hindsight. Try handling 50 cases at one time, attempting to prioritize, getting called out in the middle of the night to who knows where for who knows how long, and still doing a remarkable job of accident investigation and fostering aviation safety with no regulatory powers to mandate changes, only the duty to recommend them. These handful of investigators work endlessly, handicapped by too few trying to do too much with a woefully inadequate budget. The work they do is nothing short of remarkable. As an aviation professional, I am deeply indebted to them for their continuing and tireless dedication to aviation safety.
 
magyar
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 8:05 am


IMHO, there are two important questions to answer:

1. How come that AA had two nearly identical incidents, one near miss
and one fatal, but we do not know (not yet at least) any other airlines
experiencing similar problems? If the AA pilots following standard
procedures then why no similar incident has been yet documented
since many other airlines fly A300 around the world?

2. If the AA pilots fly an abusive way why no other airliners were
the subject of similar incident. What would have happend if Flight
903 was not an A300 but let's say a B757. How that plane would have
behaved under similar circumstances? Is the A300 particularly vulnarable
for an abusive piloting?
 
AussiePete
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 9:06 am

Any accident or incident is like looking at Swiss cheese. You can have any number of holes but the incident only happens when the holes line up in all parts of the cheese.

So, you have to consider the situation that AAL were in, how they operated the airplanes, how the airplane is constructed and the way things work etc. I find that airlines like AAL are amazing for their ability to fly over 5000 flights per day (including Eagle) yet have such a good safety record. This is despite flying in some of the trickiest weather areas in the world (from hot stormy windy to cold frozen).

As for why Airbus is different from Boeing it is generally accepted that Boeing airplanes are designed with a higher factor of safety in its structures than Airbus. This becomes evident when you put the two airplanes into heavy checks - the Airbus parts can't always be repaired.....
 
gigneil
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 10:09 am

They followed the procedures Airbus had provided them.

No, they didn't, and that's the point. Flight 903 didn't crash, and there was no problem, despite reaching the ultimate limits of the fin 3 times. That sounds like an amazingly well built airplane, one that flew many years after. Focusing on the rudder, which stayed attached, and not the pilots, which clearly were in error according to the investigation, would have been possibly even further detrimental, as I analyze below.

Obviously they are doing something wrong, at least with the A300 since the A300's tail has a hard time staying attached to the airplane.

That's a stupid statement. Only one fin has ever detached from one... and it wasn't the fin itself that failed, it was the connection point - the weakest part of any structure.

Further, its like saying "Obviously, Douglas is doing something wrong, since the DC-10's engine nacelles have a hard time staying attached to the airplane." You want to make the same statement? Probably not.

That was a case where the manufacturer recommended a specific maintenance program, and American disregarded it, and many people died.

The use of carbon fibers in place of good ole' aluminum, it's much much tougher to detect cracks in the carbon fibers than aluminum.

Boeing uses composite fins too... Even the 757 and 767 have mostly composite fins, and the 777 has an entirely composite one, as well as lots of other composite components. Many composites exibit strength MANY TIMES that of regular alloys...

other inane rambling

Its clear that there was nothing Airbus could have done to prevent 587 based on the first incident. They assumed that the fin stayed on during a little heavy action... what they didn't know was that it really stayed on during FAR MORE HEAVY action. If they had learned that, they might have been even more lax with their recommendations.

I don't know how you can equate parts survivability to safety. It can't be done. If the part needs to be replaced or repaired, they do it. Its a cost issue not a safety one... and saying that means Airbus is unsafe is retarded.


There are some members here with rampant anti-Airbus rhetoric that also make valid assessments most times. They're well respected by me and others. There are others with analysis like "obviously they're doing something wrong", and I certainly hope they are incapable of reproduction.

N
 
tekelberry
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 12:04 pm

No, they didn't, and that's the point. Flight 903 didn't crash, and there was no problem, despite reaching the ultimate limits of the fin 3 times. That sounds like an amazingly well built airplane, one that flew many years after. Focusing on the rudder, which stayed attached, and not the pilots, which clearly were in error according to the investigation, would have been possibly even further detrimental, as I analyze below.

The article made it clear that an airplane like that shouldn't have had a problem with the fin.

That's a stupid statement. Only one fin has ever detached from one... and it wasn't the fin itself that failed, it was the connection point - the weakest part of any structure.

But that doesn't count, of course? :rolleyes:
 
gigneil
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 12:12 pm

The article made it clear that an airplane like that shouldn't have had a problem with the fin.

It didn't. The article made that clear as well. That flight landed safely and flew for many many years after with no trouble. Do you need everything dictated in an article, or can you make an assessment yourself?

But that doesn't count, of course? :rolleyes:

Of course not, just like the DC-10 that toppled out of the sky over O'Hare after an engine fell off didn't count, or the 737 that had just left Peterson Field near Colorado Springs that went down due to its many fun rudder problems doesn't count either. :sticks out tongue:

You can't say the plane has problems with keeping its fin on when only one has ever come detached... that's hardly a sufficient sample size given the many millions of hours the A300 has accumulated. If it did have problems keeping its fin on, flight 903 would have crashed as well.

Keep on responding to lengthy posts with mature one liners. Its fun for everyone. Not.

N
 
AussiePete
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 12:40 pm

I fail to identify with statements such as "only one has ever fallen off". Using statistics to justify such events is not what the aviation industry is about. If it was, Boeing would not be modifying rudder systems on the 737 because, frankly, the stats will show that 2 or 3 events over the lifetime and hours/cycles flown by the 737 makes it a small issue.

The fact is that everyone here is neglecting the fact that the investigation into the New York crash uncovered a factory rework which was traced as the initial failure of the structure. The fact is that the vertical stabilizer is more or less primary structure and it seems that the Airbus A300 in the accident was a victim of a one off series of events as opposed to any design flaws. It also represents an early use of composite and aluminum structures used in tandem that would almost certainly not be designed in the same way today - however that doesn't mean it is necessarily wrong.

The issue in this story is not the airplane, it's the handling of information and the disclosures or non-disclosures by stakeholders in the matter. Perhaps discussion should concentrate on that?
 
gigneil
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 1:08 pm

I'm not at all trying to justify the event with statistics. From a moral/ethical perspective, no event that causes the loss of life can be justified.

I'm trying to say that one line statements saying "they must be doing something wrong since the plane has trouble keeping its fin on" is based on an improper induction - a hasty generalization.

I am neither defending nor indicting Airbus in the matters of the investigation - I'm hardly in the position to do so intelligently. I'm indicting inflammatory comments with vapid groundings.

N
 
T prop
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 3:34 pm

They followed the procedures Airbus had provided them.

No, they didn't, and that's the point.

In June 1997, Airbus requested that American Airlines perform another inspection of the jet to ensure it was not damaged. American inspectors, following Airbus' instructions, examined the tail fin. But they did not use methods that would have allowed them to see inside the tail fin. They saw no damage from their visual inspection, and the jet continued to fly for nearly five years.
--------------------

If Airbus requested American inspect the tail per thier instructions, then the personel doing the inspection would have done just that. If Airbus says perform a detailed visual, someone has to sign off on this. If Airbus said that the inspection MUST include ultrasound or x-ray, then American would have done it and signed off on it. If they didn't do ultrasound or x-ray that's because Airbus didn't require it.

Why would anyone not follow exactly what the manufacturer instructs? By not following thier instructions exactly you release them from liability. Americans inspectors did exactly what Airbus required.

T prop.






 
Staffan
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RE: Near-crash Uncovers Crack In Air Safety System

Wed May 28, 2003 4:24 pm

"Why would anyone not follow exactly what the manufacturer instructs? By not following thier instructions exactly you release them from liability. Americans inspectors did exactly what Airbus required."

Put in another way: Why wouldn't Airbus instruct AA to do the inspections in a sufficient way if they knew there might be a problem.

Rules and regulations are easy to set up, but it's harder to make sure people follow them.

Staffan
 
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PW100
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RE: Near-crash Uncovers Crack In Air Safety System

Thu May 29, 2003 3:04 am

People fail to understand that the problem here is not the structure of the airplane. The JFK A300 crashed because the vertical tail sustained forces exceeding the max load of the tail. In other words, the tail was not designed to sustain these forces. Or more boldly: the tail was supposed to break off at these loads! It did exactly what the designers [and regulators including JAA and FAA] certified this plane for.

The Miami A300 [903] incident resulted in the tail being overstressed beyond the max design limit [including the 1.5 safety factor] for three consecutive times! Who needs further proof that that tail is damn strong and even better than what it was designed and certified for! It was stressed not only over its ultimate design load, it was not only stressed three times over its ultimate load, it even kept on flying for another 5 years after suffering these extreme forces!! Nobody can claim that that tail wasn't/isn’t strong enough. I seem to have read somewhere that when the Miami A300 had its tail replaced, that although it was damaged, it still had sufficient strength to be safely loaded up to it's design load.

The question here off course is WHY did these aircraft end up in a situation where it was bound to exceed the max design load of the tail? Off course it has something to do with AA training. And off course it has something to do with the pilot/aircraft control interface [ie rudder movement vs. pedal travel/pedal force, force feedback on pedal etc.].
Most likely the crash and near-crash were a result of these factors COMBINED [*AA training, *A300 rudder control interface]. Factors which each on their own will not bring an aircraft down, but combined proved to be lethal.

So who is to blame?
AA basically says that if the rudder control interface had been better it would not have happened, Point for AA: it never happened to any other aircraft within the thousands of aircraft that flew/fly in AA colours so it can not be AA training related.
Airbus quite rightfully says that without the AA training of excessive rudder use it would not have crashed. Point for Airbus: It never happened to any other airline on the A300/310 or any other airbus at any airline so it can not be A300 related. Airbus apparently even warned or questioned AA training on excessive rudder use.

So who is to blame? I don't know. The truth usually is somewhere in the middle...
However just shouting blindly that Airbus is unsafe, Airbus tails tend to fall off etc. is just blatantly ignorant. I would expect this from uninformed media, but not from aviation insiders on this forum.
Every Boeing "fan" using this opportunity to once again flame Airbus, I kindly remind you that Boeing doesn't exactly have a clean sheet themselves either. Remember the JAL 747 that crashed due to the rear bulkhead damaged in a tail strike. The China Airlines 742 which crashed last year is now also strongly suspected to have been caused by rear bulkhead damage due to a tail strike previously. I'm sure there are more events like this between both Airbus [A300-600R stalls, A320 CFIT] and Boeing [737 rudder, 747 engine break aways].


PW100

PS. Ironic thing is that this is the very reason Airbus went for fly-by-wire. A flight control computer will not accept these types of rudder inputs that would result in overstressing the airframe.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
gigneil
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RE: Near-crash Uncovers Crack In Air Safety System

Thu May 29, 2003 3:18 am

T Prop-

We're talking about different instructions. The original poster was talking about pilot training.

N
 
redngold
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RE: Near-crash Uncovers Crack In Air Safety System

Thu May 29, 2003 4:25 am

Link to story (USA Today, 27 May 2003):
http://www.usatoday.com/news/nation/2003-05-26-a-cover_x.htm

I hope that before you post that this is a "sensationalized" article, try watching the animation of what happened. Then you can come back and post your views, once you've "seen it first-hand." I know it made me sick.
http://www.usatoday.com/news/graphics/g903/flash.htm


redngold
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Bruce
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RE: Near-crash Uncovers Crack In Air Safety System

Thu May 29, 2003 5:18 am

Quote,

"Only last March, as part of the Flight 587 investigation, did Airbus conduct an ultrasound inspection of the tail fin on the jet involved in the 1997 incident. The inspection found two crescent-shaped cracks at one of the points where the tail fin attaches to the fuselage. The fin was replaced"

I dont understand something. This is saying the fin was replaced?? On the jet that crashed? Or was the 1997 incident a different aircraft than flt 587.


bruce
Bruce Leibowitz - Jackson, MS (KJAN) - Canon 50D/100-400L IS lens
 
redngold
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RE: Near-crash Uncovers Crack In Air Safety System

Thu May 29, 2003 5:22 am

The 1997 incident involved a different A300. The cracks were found in the tail of that plane, not in the Flt. 587 aircraft (at least not prior to the accident invesigation.) The tail was subsequently replaced on the 1997 incident aircraft.

Why Airbus wouldn't recommend, or American require, a boroscope inspection after such incredible stress is beyond me.


redngold
Up, up and away!
 
Ikarus
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RE: Near-crash Uncovers Crack In Air Safety System

Thu May 29, 2003 7:49 am

I watched the animation. Sickeningly sensationalized.

Regards

Ikarus
 
magyar
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To PW100

Thu May 29, 2003 8:04 am

Nicely said, these were my thoughts exactly.

One thing you should know though! This is not a responsible forum,
so you should not expect any objectivity. The crowd here is a mixture
of reasonable people and idiots. The good thing is that sometimes you
can run into useful and interesting information/thoughts in the midst of
the background shit.
 
Scorpio
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RE: Near-crash Uncovers Crack In Air Safety System

Fri May 30, 2003 2:09 am

STT757,

I've noticed on various occasions that you say things which are blatantly false, and which you fail to back up in any way. When corrected, you ignore the corrections and repeat your incorrect statements. Let's see what you do with this one:

Eastern had similar problems with the A-300s, finding cracks.

Did you know that Eastern's A300s were A300B4-200s, an earlier model than the A300-600R used by AA? Well now, the A300B4-200 DOES NOT HAVE A COMPOSITE TAIL.

Aussiepete,

As for why Airbus is different from Boeing it is generally accepted that Boeing airplanes are designed with a higher factor of safety in its structures than Airbus.

Do you have any numbers or statistics to back that statement up?
 
Guest

RE: Near-crash Uncovers Crack In Air Safety System

Fri May 30, 2003 4:51 am

That animation was incredible!

Stephen
 
747-451
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RE: Near-crash Uncovers Crack In Air Safety System

Fri May 30, 2003 7:46 am

"Although overcontrolling an airplane is generally not a good thing, I think it is peculiar that pilots can actually snap off the tail through rudder use in an otherwise normal flight profile"

What exactly is "over controlling", since in this case managing wake turbulence from a much larger heavier aircraft shouldn't be considered out of the ordinary. Secondly, I would hope that greter tolerances like this would be considered.
 
AussiePete
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RE: Near-crash Uncovers Crack In Air Safety System

Fri May 30, 2003 8:31 am

QUOTE from SCORPIO:

Aussiepete,

As for why Airbus is different from Boeing it is generally accepted that Boeing airplanes are designed with a higher factor of safety in its structures than Airbus.

Do you have any numbers or statistics to back that statement up?
---------------------------------------------------------------------

No, but having previously worked as a structural engineer including reviews of new model airplanes I think I have seen the data to know what I say is true. Short of copying proprietary data onto this forum I see no other way to back it up. It is an observation of two different ways of doing business - both have their advantages and disadvantages. Neither is inherently wrong however those who decide which aircraft to purchase need to prioritise which way is going to work best in their operational environment.
 
AJ
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RE: Near-crash Uncovers Crack In Air Safety System

Fri May 30, 2003 8:33 am

The aviation industry continues to run on a 'tombstone imperative', or to expand nothing changes until someone dies.
Generally after an accident the media goes crazy, with the industry forced to deny everything to ensure survival.
Then the first stage of learning starts. The airlines issue crews memos that basically say 'do not crash the aeroplane'. The investigators release initial findings that can be interpreted many ways (especially on a.net!).
Then it goes quiet for a while.
Then this sort of reporting starts. The investigators release findings that vary from specific (most times) to vague (737 findings), and make recommendations to the regulator to fix the cause. Manufacturers, airlines and everyone else involved scramble to avoid possible legal action by adding disclaimers to any response, such as the reactions we've read above.
It is during and after this stage that some good is found. Crews are trained to avoid potential accidents with the new findings (ie. aquaplaning after QF1/Little Rock, jet upset recovery after AA587 etc). Engineering/manufacturers receive training and information on how to improve the safety of aircraft components. Regulators learn what to target on audits of particular airlines and aircraft (ie Valujet and Air Florida) and so on.
In the end the same aircraft of the same airline at the same location should depart a safer operation for the fare paying passenger.
In the case of the A300-600R the 'new' composite fin held a flaw. In line with the tombstone imperative the aircraft will now be made safer after an accident. I would imagine that a rudder limiter will be installed that simply will not let the crew overstress the fin.
The same learning curve has been followed by the many types by most manufacturers, for example the A320 (FBW/Human interface), B737 (Rudders), B737/747/757/767 (CWT Pumps), DC-10 (Cargo doors and maintenance procedures), the Comet (Fatigue, crew training) and the MD-11 (wiring).
It is hard to predict the next cause of an accident as we go through stages of emphasis, such as CFIT and fuel pumps. The threat is significantly reduced by the use of the Reason model mentioned by AussiePete, and airliners are generally flown conservatively and safely with very few deliberate accidents in normal operations (unlawful activity aside).
Nobody of sound mind should be blaming anyone as the lessons learned are invaluable, in this case about composite construction.
Any coverup of known problems should be persued and prosecuted as that is unlawful knowledge, but Airbus would not be the first. The classic example is the DC-10. Continental knew of DC-10 pylon problems caused during non-approved engine changes but this information never made it to American Airlines via the FAA, resulting in the O'Hare accident. The manufacturer and the FAA were both aware of the cargo door problem after the 'Windsor' incident, but stopgap repairs to protect the DC-10s image did not prevent the tragic loss of THY's aircraft at Ermonville. This sort of deception is unforgivable, and those involved should be forcibly distanced from the industry.

That's my thoughts on the issue, not Airbus vs Boeing, not AA vs FAA, just the way a technologically advanced industry learns.