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Roger Mazengarb

Interesting story of a past AA crash

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Interesting article. Thanks for the link Howard.

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The things I can't figure out:There are few times when the indicated airspeed is slower than when a plane has just taken off. If the tail can't tolerate full rudder deflection at such low speed, why is the rudder designed to deflect so far?What's the logic in using so mush rudder to counteract a roll? I thought that was the aileron's function.There's been mention that there may have been wake turbulence from a heavy at the root of this incident. Were medium weight transports being routed to avoid the wake from the heavies and was the plane traveling along that route? Was air traveler safety sacrificed for noise abatement?

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Hi RobertVAOne of the reasons the rudder has so much authority is in order to retain control if an engine fails. Twin engined aircraft with wing mounted engines always need to remain control in order to gain certification, and the more powerful the engines the bigger the rudder area.As regards correcting for turbulence, I can only speak as 40 hour PPL student. My instructor keeps reminding me that when I use the ailerons to correct for turbulence, I should use coordinated rudder input as well (and vice versa). I don`t know the details of the control movement immediately prior to the loss of the fin but there may well have been rudder + aileron input. CheersRottenlungs.

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Hey all.So many factors in this incident, really unfortunate.We have an aircraft departing without standard wake seperation behind a heavy 747. It has been suggested that conditions during the event were conducive to, not necessarily stronger, but more well-developed and long-lasting wake vortices.We have the A300 rudder limiter, which, though it may not be flawed, per se, it becomes extremely sensitive at the speeds of the incident, and is most certainly a factor, though not in itself the cause.Then, we have the combined factors of AA's upset training program, and a bit of miscommunication between AA and Airbus.Resolve just one of these issues, and there is no accident. Instead, a 6.5 second event results in tragedy. RIP

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This was a while back, but if I remember correctly there was a report that the heavy taking off before this ill-fated Airbus was cleared for takeoff, but took an abnormally long time to begin its roll. The Airbus was then cleared for takeoff, but if the tower was measuring separation from the time of clearance, then the safety window was considerably shorter than it should have been.Unfortunately, the news stories on this indicate that this problem will be "settled" by lawyers, not resolved by engineers and pilots. Of course, there will be a parallel track which will include appropriate pilot training and possibly some aircraft modifications, but I'm afraid the focus will be on the inevitable lawsuits rather than on lessons learned.

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Great point.I just watched "Fate is the Hunter" on cable last week...based on the Earnest K. Gann novel about a post-crash investigation. There really are a lot of little things that contribute to a catastrophe, any one of which can affect the outcome. Kurt

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You can find the NTSB animated accident reconstruction here:http://www.ntsb.gov/events/2001/AA587/NTSB...truction587.wmv"This three-dimensional animated accident reconstruction shows most of the flight for American Airlines Flight 587, which crashed shortly after takeoff from JFK International airport on November 12, 2001. The reconstruction exhibits information selected from the Flight Data Recorder, excerpts from the Cockpit Voice Recorder transcript, recorded radar data and aircraft performance data. This reconstruction does not depict the weather or visibility conditions at the time of the accident."(Quote from http://www.ntsb.gov/events/2001/AA587/anim_587.htm )Jozef http://pluizig.ath.cx/signature.jpg

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I posted this at fs.com as well:I think it's really ridiculous to scapegoat the first officer in this incident the way the final report did. The fact is that it should not be possible on a large passenger aircraft for the pilot to rip the vertical stab off with *any* amount of rudder input. If Airbus knew there was a potential problem with structural stability near full travel, they should have designed a system to limit the rudder input based on speed or something to that effect to ensure this couldn't happen. (with how many methods of limiting the pilot later Airbus aircraft have implemented, this shouldn't have been difficult) The FO obviously wasn't aware that this was a possibility and sadly, as the CVR transcript shows, neither pilot even figured out what had happend before they crashed. I'd be much more inclined to fault Airbus and AAL's training for this, than the pilot who was acting as he was trained to do. To blame a person who obviously can't offer a defense is pretty low IMO.

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I'd like to throw my support behind the First Officer who is now the scapegoat for the crash.How in the name of God does the FAA certify an aircraft for commerical passenger travel if it is possible to rip the entire tail off by applying too much rudder pressure! :-hmmm To make matters worse, assuming Scarebus and the FAA DID know about this issue, you'd think that they'd put a rudder travel limiter in place to prevent this for happening? :-hmmmmCould you imagine this in the automotive industry that if you turn the steering wheel to far to the left or right the front end of the car would rip off? Or if you stepped on the brake too hard the brake calipers would pop off?The outcry would be so great and the law suits would flow like the Colorado River in spring if even one mini-van full of soccer moms and kids went careening over a cliff just by turning the steering wheel too hard. Much less an Airbus A300!How bad is it to place blame on a man who is no longer here to defend himself? I'm stunned at the pure insanity in the world in which we live.Mike T.

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>>I'm stunned at the pure insanity in the world in which we>live.>>Mike T.>>>>Perhaps that is because you do not understand all of the factors that were involved. The tail was not ripped off because the first officer applied "too much rudder pressure." The A300-600, as with all large transport airplanes, does have a rudder travel limiter that limits rudder travel as a function of airspeed. The FAA's certification requirements require the airplane structure to be able to handle a maximum rudder input, followed by centering the rudder, at speeds up to the airplane's dive speed.This was not a matter of pushing on the rudder pedal to hard or for too long, so your comparisons to turning a steering wheel too far or stepping on the brake too hard are faulty. What happened is that the First Officer made repeated full rudder inputs from one side to the other in very, very rapid succession. As you can imagine, the loads generated by successive full rudder oscillatory motions become extreme, and eventually exceeded the strength of the tail.The NTSB found the first officer's rudder inputs were excessive and unnecessary. Contributing factors were the A300-600's rudder system characteristics (sensitivity) and the American Airlines training program for upset recoveries.The first officer was not picked upon as a scapegoat, nor is he treated differently or deferentially because he perished in the crash. The NTSB deliberations considered scads of evidence, testimony, etc. for over two years, including animated recreations, simulator work, etc. The amount of hard work, perseverence, and sacrifice to get to the bottom of this accident should not be dismissed too quickly. At least read the full report and ask questions before dismissing their findings.

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shortly after the accident, aviation week had an article explaining the danger of excessive loads caused by stop-to-stop rudder application. it seems to be more surprising that the tail stayed on as long as it did, rather than that it came off.one thing that came out of this is that boeing, airbus and the faa collaborated on a very good video (with supporting text) on upset recovery. some misconceptions on rudder certification requirements were also addressed.

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Trust me, Mike understands.......he was a commericial pilot for a national carrier before he changed positions to do what he is now, and I for one back his statement 10000%Clayton T. DopkeMajor, USAF (retired)"Drac"

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"Or if you stepped on the brake too hard the brake calipers would pop off" :-lolMan, it's a good thing the world series has my attention or I would still be laughing at the way that is worded and envisioning that happening. Carmine http://ftp.avsim.com/dcforum/Images/wave.gif

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I agree, First Officer not only applied oscillating force but he applied LOTS of it. 140 lbs. of force to be exact. That is equivalent to lifting a weight of an average woman with your foot!I am not sure any hard protection envelope can be implemented in an aircraft that is not fly-by-wire. In a non FBW there will always be forces that crew can impart to controls to trigger catastrophic chain of events - for example they can push very hard on the main columns and cause a dive that would exceed design limits of the aircraft. Or pull too hard to cause excessive G-forces. So folks that claim that something shouldn't have been possible to be done are totally off base. The same way you could argue that steering in a car should have limits that would vary depending on the speed of the car. Well, fine, if we have drive-by-wire cars then maybe right now we are living in the practical world. Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2, Omega 2.7.90 (4xAA 16xAF)

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Sum it up in one word, Scarebus.This FO was a son of a captain at the same airline. I find it very hard to believe he did much of anything wrong. Plenty of AA pilots came out after this and stated they will not fly Airbus and want transfers to Boeing equipment. They had also stated they'd never heard in all the years of flying many different types of aircraft that this rudder deflection was something they should be aware of. They don't believe a Boeing would've fallen apart at all.

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Scarebus,Yep that pretty much says it all. Having flown aircraft, driven racing cars and the like all I can say is that it is my not so humble opinion that regardless of what the FO, pilot, flight attendent, cook, passenger, short of disassembling the tail section, the tail, rudder, vertical stabs and such should have stayed on the aircraft and functioned. For them to do anything else is a design problem of the first nature.Personally, I don't and won't fly in anything that say's Airbus on it. That is MY choice . . . your mileage may vary.Best to all,Clayton T. DopkeMajor, USAF (Retired)"Drac"

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Sorry, but I must respectfully disagree with you. It is obvious from Mike's comments, as I pointed out, that he does not understand. And I don't care what he did before he changed positions. If he thinks that the tail came off from one input of full rudder, and furthermore believes that the A300-600 does not have a rudder limiter, he does not understand.

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I hate to burst your bubble, but rapid, full rudder inputs applied in an oscillatory manner can break the tail off of any transport category airplane, Boeing included.

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Yes, immediately after this crash ALL airline manufacturers, including Boeing, issued a safety bulletin stating that repeated stop to stop rudder movements should not be carried out while in flight. Not a single large modern airliner is designed for such action.The tail on this A300 actually exceeded its maximum design load by some way before it snapped. So yes, it is amazing the tail stayed on as long as it did.Its a miscommunication by all airliner manufacturers and airlines. Like many past cases, a problem is often only found after an accident occurs. Its happened with the Comet and its happened with the 747 cargo door locks

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Hey guys.The rudder/rudder limiter itself, again, not the cause, but a factor none the less. Now, there was obvious misunderstanding here, as to how the limiter operates, but it in and of itself was not the problem.The breakout force, the force required to move the rudder at all, and the force required to go full stop, are very close, at speed. In fact, post-accident tests that involved line pilots, and even an Airbus test pilot, showed that it is impossible to modulate, say a half-deflection only, at the speeds of the accident. At this stage, the rudder pedals become more of an on-off switch, giving all or nothing.PF encounters upset, applies what he feels is a small amount of rudder to stabilize. He gets full rudder deflection, and an obvious unwanted response from this, so he corrects the other way, and again gets full rudder deflection, in the opposite direction. PIO if there's ever been.That fin took a pounding before it departed the aircraft. I honestly believe that A300 operators have taken heed to this investigation, regardless of what the current report shows. The battle now is over who pays the bill, not what can be learned. I don't believe we will see this again.

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Oh yes, because a Boeing has never crashed due to a rudder defect, has it?:-roll

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>Sum it up in one word, Scarebus.>>This FO was a son of a captain at the same airline. I find it>very hard to believe he did much of anything wrong. Plenty of>AA pilots came out after this and stated they will not fly>Airbus and want transfers to Boeing equipment. They had also>stated they'd never heard in all the years of flying many>different types of aircraft that this rudder deflection was>something they should be aware of. They don't believe a>Boeing would've fallen apart at all.If it ain't Boeing, I ain't Going!!!

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What a frightening animation.May they Rest in Peace.

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You win the solid gold award for accuracy Brian, the A300-600 rudder limiter is a bad design compared to Boeing

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