spacecadet
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AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:13 am

I think the media and a lot of people here have been looking at this the wrong way. The tail fin was found intact in Jamaica Bay - a mile *behind* the main wreckage and two engines. The NTSB just said they've found no evidence of uncontained engine failure, no evidence of birdstrike, and no sound of any kind of explosion on the cockpit tape or any talk of engine problems. In fact, what they heard was airframe shuddering and talk of wake turbulence 20 seconds before the crash.

I think the tailfin somehow ripped off the plane and initiated the breakup process. With no tailfin, the plane would go into an uncontrolled yaw that would put aerodynamic loads on the engines that they were not designed for, possibly ripping both of them off. This is the only explanation that really explains the distribution of the debris field, and it's supported by the CVR tape.

Anyone else agree? It's looking to me like, once again, initial speculation has turned out to be dead wrong in this crash. Of course, this still doesn't explain how the tail tore off, but I think that's where the crash originated, not from the engines.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
Guest

RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:18 am

I just heard on MSNBC during the NTSB news conference that on the cockpit voice recorder the pilots are talking about wake turbulence from another aircraft. A JAL 744 took off right before the A300. Maybe the wake turbulence had something to do with the accident. The FDR has also been found.
 
voodoo
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:20 am

And where have we had a tail fin separation before?
That JAL 747 that flew around afterwards barely in control before hitting a mountain.
What caused that? A crack in the pressure dome
after a faulty maintanance after a tail strike (correct me if wrong) on the runway.
But that blew out at a higher altitude due to pressurization.
So *if* this is at all similiar: what caused a rear fuselage blast?
` Yeaah! Baade 152! Trabi of the Sky! '
 
Ikarus
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:21 am

Don't forget to mention that you are just speculating, too. Based on very little information.

I disagree on your theory. Even without tailplane, there is no immediate reason why the plane should go into so powerful a yaw that the engine pylons cannot withstand the stress - a scenario I find hard to imagine anyway. True, lateral stability would be lost. But how should that cause structural damage of this degree?

You mention that there is claimed to have been "talk of wake turbulence 20 seconds before the crash". If that is correct, the real question might boil down to "What effect that can be perceived as wake turbulence by a pilot can cause a fatal accident of this nature?"

And frankly, I have no idea. Let's just wait until the investigators come up with verifiable theories, shall we?

Regards

Ikarus
 
Ikarus
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:24 am

Voodoo: The 747 in question lost its tailfin. It also lost all hydraulics and therefore all control over the control surfaces - the only means of control left was alternating thrust on the LHS and RHS engines.

In this case, if the tailfin was indeed lost before the breakup, there is still no viable explanation why it should cause the engines to separate, or structural breakup. Loss of control - yes. But loss of engines? How?

Regards

Ikarus
 
AWspicious
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:26 am

Could an aircraft of that size break apart due to aerodynamic stress from only 2800 feet?
Nevermind political correctness - Envision using your turn signals!
 
voodoo
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:34 am

Ikarus, I am not sure which is more liable to the double separation we have seen:
i.e.
a) fin, then engine or
b) engine, then fin.

But since the planes are designed to cope with the latter i.e. engine separation and not the former,
then it does seem possible that the fin came off, then the engine.
` Yeaah! Baade 152! Trabi of the Sky! '
 
mika
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:38 am

Put into the account that they were travelling at max 250 knots if they were below 10.000 feet. I find it hard to believe that any part of the plane (aside from the vertical stab. maybe) couldn't withstand such forces.

But then again, i'm no physics expert. just my 2 cent's worth.
 
TAA_Airbus
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:41 am

Maybe, and just maybe, the plane was a flying bucket of sh*t, and infact was an accident waiting to happen.

Who knows.
 
spacecadet
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:42 am

Ikarus: There's nothing wrong with informed speculation. This is a discussion board, not a "shut up and let the professionals do their work" board. My point in writing this post was to get people thinking on a possible track that I think is much more likely than the one dominating other threads here. We've got 46 messages and counting in a birdstrike thread, when there's absolutely no evidence of that whatsoever.

A wake vortex should never be severe enough to sheer off a tailfin, but it *could* be severe enough to put a following plane *without* a tailfin into a progressively worsening yaw. I also mentioned on another thread that it was a pretty windy morning yesterday (I live in Queens), so even without the wake turbulence there was plenty of wind to knock a plane missing a tail fin around.

With no means to correct such a yaw, the sideslip would only continue to get worse as airspeed increased during descent. The engines were found *close* to the main wreckage - just a couple blocks away - which suggests that they were detached just prior to the plane's crash, probably when it was traveling at a high rate of speed and at maximum sideslip. The fin, however, was found a mile behind the main wreckage, and was more than likely a separate event.

Voodoo: The JAL 747 you speak of had a rear pressure bulkhead failure that was clearly audible on the CVR tape and that blasted the entire rear end of the plane off the fuselage. It was not a clean break as was the case in this crash (about half of the fin was still on the plane, the metal torn and jagged - you can see this in pictures of the flight). It also happened at a much higher altitude where the pressure inside the fuselage was much greater. AA 587's tail fin looked like it had just come off the assembly line when they fished it out of the water - it didn't get blown off the plane or otherwise ripped off by external debris. Seems like two different kinds of failures to me.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
LuckySevens
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:01 am

I still think this looks like the Lauda Air incident.
The reverser deployed and the plane self-destructed mid-air.
 
redngold
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:12 am

I wondered if the vertical stabilizer could have been "blown away" from the plane by the impact but now see that the ensuing damage from that type of explosion did not occur. It seems the vertical stabilizer came off first.

redngold
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jfs9900
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:23 am

LuckySevens - If the reverse thrusters had been deployed wouldn't the pilots have had some indication of this and may have mentioned it in their conversations? Unless.. (and this theory is probably off completely) one or both of the pilots intentionally deployed them? This would most certainly show up on the FDR It cause of the crash seems more complex.
 
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GreenArc
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:29 am

Rudder hard over? Rudder is completely missing from vertical stabilizer. Vertical stabilizer broken off at factory join.

Just wondering aloud.

GreenArc
 
heavymetal
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:29 am

Interesting theories folks but you're ignoring the obvious....a lost tailfail wouldn't damage the engines in the slightest. And given the aircraft's speed and altitude I just can't see how an engine would have seperated based on the lateral forces that would accompany a gradual uncontrolled flight.

I'm still inclined to believe something really bad happened out on that engine, something mechanical...but I'm just as concerned at this point that if there was ANY kind of foul play involved, that it's being withheld in the interests of the airline industry and the economy.......
 
Guest

RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:34 am

The reverser deployed and the plane self-destructed mid-air

The Lauda accident the aircraft was crusing, so when the revers thrust deployed there was incredible stress on the aircraft. I highly doubt that a reverse thrust deploying at such a slow speed would cause such structual damage!
Iain
 
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GreenArc
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:35 am

>>Tuesday November 13, 6:01 pm Eastern Time<<

>>American 587 engines show no internal failure-NTSB

NEW YORK, Nov 13 (Reuters) - A preliminary inspection of the engines from doomed American Airlines(NYSE:AMR - news) Flight 587 showed no evidence of internal failure, investigators looking into what caused the airliner to crash, killing up to 265 people, said on Tuesday.

``Initial inspection shows no evidence of any sort of internal failure of engines. They all appear to be in one piece,'' said NTSB member George Black at a news conference.<<

>>At the news conference, Black said initial analysis of the cockpit voice recorder revealed that the plane rattled loudly twice before pilots lost control.<<
 
TWA717_200
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:45 am

The Lauda accident the aircraft was crusing, so when the revers thrust deployed there was incredible stress on the aircraft. I highly doubt that a reverse thrust deploying at such a slow speed would cause such structual damage! Exactly what I was thinking. For once, Iain and I agree on someting.  Smile

As for Spacecadet's theory, it's certainly as plausible as any. Especially for the amount of information that has been released.
 
Guest

RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:52 am

Correct me if I'm wrong, but the Lauda incident was during climb, not cruising!!! If memeory serves me correct it crashed against a mountain.
 
woodsboy
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:55 am

Sounds very likely to be related to wake-turbulance and a failure or upset of the tail.

Too bad the media are already holding funeral services for the GE CF6 engine, they are "flying death pods" dont ya know.

If anybody wants a good laugh, go see what the Yahoo message board looks like regarding the news of the Cockpit Voice Recorder. People are soooooo retarted, its embarrasing.
 
Guest

RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 8:55 am

"Shortly after takeoff, a REV ISLN message appeared on the aircraft's EICAS system alerting the crew that there was a malfunction with the thrust reverser isolation valves. The crew opted to continue the flight, and as the aircraft approached FL310, the no.1 engine thrust reverser engaged. The incredible force on the aircraft caused the airframe to break apart within several seconds."

Sorry, my bad...
 
Klaus
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GreenArc

Wed Nov 14, 2001 9:01 am

GreenArc: ``Initial inspection shows no evidence of any sort of internal failure of engines. They all appear to be in one piece,'' said NTSB member George Black at a news conference. [...] At the news conference, Black said initial analysis of the cockpit voice recorder revealed that the plane rattled loudly twice before pilots lost control.

That would still leave the engine pylon fatigue issue in the game.

By the way, one eyewitness explicitly said she saw the plane go down "in one piece, fuselage, wings and tail". She didn´t mention the engines, if I remember correctly, but she might be right in what she said.

I could imagine the tailfin being tossed a few meters into the water on impact.

But with the flight data recorder recovered (and hopefully intact), I´m pretty sure we´ll know much more very soon. An engine separation would be very noticeable. Especially if it came with no previous vibration or other irregularity.
 
TWA717_200
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:10 am

By the way, one eyewitness explicitly said she saw the plane go down "in one piece, fuselage, wings and tail". She didn´t mention the engines, if I remember correctly, but she might be right in what she said.

Another witness said that he saw the entire wing fall off before impact. One saw this, one saw that.
 
Pilot1113
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:18 am

The tail is bolted on to the rest of the plane. It's quite possible that the bots didn't get torqued properly during the last maintenance check.

That JAL 744 was 8 miles ahead of the A300, so wake turbulance couldn't have been a problem.

It's very possible that the tail came off shortly after takeoff leading to unstable flight. During the wild yaws, the copilot called for max thrust and increased the loads on the engines causing them to come off.

The Wall Street Journal is saying there is evidence of FOD, which I think can be attributed to other parts coming off and getting ingested, thereby increasing the loads even more.

It really doesn't take much for an engine to come off. Anyone remember that NWA 727 that lost an engine after getting repeadily hit by ice chunks from the leaky lavatory?

- Neil Harrison
 
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RayChuang
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:33 am

It's beginning to sound like that the structural design of the A300B4-600R could be at fault.  Sad

Remember, these planes were built in time when structural parts being bonded together with adhesives were still a relatively new idea. There has been quite a lot of concerns from mechanics about the quality of the adhesive joins in the long run. It's small wonder why Boeing has not really used adhesive joins until the 777 program, more or less.

I think there's a possibility that structural failure of the vertical tail--which ripped it off the plane--caused the plane to undergo severe aerodynamic yawing and structural stress, which eventually broke up the plane.

It appears that Airbus may have to issue an immediate directive to all A300/A310 operators start inspecting all structural joins very closely.
 
spacecadet
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:41 am

We know the engines came off; that's not an issue. The point is that they both came off 2 blocks from the crash site. The fin came off a mile from the crash site, intact. There's no way the fin gets thrown that far from the crash site if it's still attached at impact (this was not a "few meters" - this was a mile away), especially not in that condition.

I'll agree with whoever said you can't go by eyewitness accounts. The NTSB doesn't rely on them either; they're a piece of information but about the least reliable piece of information. I saw one guy yesterday who said the whole tail came off first; I discounted it at that point because they hadn't even found the tail yet in the water, but that just proves that it's the physical evidence that matters most. Plane crashes are by nature surprising events that defy what we expect to see when we look at an airplane; our memories are not reliable when trying to recall exactly what we saw.

Starting to see the media come around to the fin theory now. CBS mentioned it as being possibly the key to the puzzle tonight; MSNBC and FoxNews are still stuck on the death-pod engines, though, despite the NTSB briefing today where they basically said the engines looked perfectly fine so far. I'll be surprised if the engines had anything whatsoever to do with this crash.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
Treg
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:51 am

But hey, look at the picture. The tail is virtually cut off. Pure and clean cut. No damage what-so-ever. It is impossible that there was some foreign object (an engine, big bird if you like) colliding with the tail. It has to be either structural or due to the heavy aerodynamic load. The rest was just a chain reaction. I can not imagine anything else. Correct me if I am talking nonsense (and don't blame me about speculations - it is a discussion forum).
 
voodoo
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:52 am

Differing from the earlier A300B4,
the A300-600R has the tail structures of the A310.
Do these have a fuel tank in the fin and or stabs?
Did the stabs end up in the bay, or were they with the main fuselage?
` Yeaah! Baade 152! Trabi of the Sky! '
 
Guest

RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:07 am

I haven't seen any info on regarding the condition/location of 587's horizontal stabs, and I've been looking everywhere. The video of that pristine vert stab is really troubling, though.
 
houstondallas
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:11 am

I'm guessing that the tail section seperated from the aircraft. The rattling that was heard on the CVR was probably the fuse shaking like crazy due to the fact that there wasn't a tail attached to the aircraft to give it stability. All of that shaking may have hit a resonant frequency that caused the engine pylons to fail. This explains why both engines seemed to seperate before impact. That's my 2 cents.
 
heavymetal
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:12 am

"It's very possible that the tail came off shortly after takeoff leading to unstable flight. During the wild yaws, the copilot called for max thrust and increased the loads on the engines causing them to come off."
---
Can you achieve thrust loads on the engines with the throttles that would cause the engines to come off? I'm fairly certain you can't.

Here's another thing that intrigues me....SOMEWHERE surrounding JFK there HAS to be a video camera pointed at the airport....a traffic camera, a web cam, a security camera, even a camera at an ATM....I just find it hard to believe that some if not all of this event isn't on videotape somewhere.

It's ironic that if this aircraft had made it a few more yards, the main fuselage would have impacted in the ocean....saving the Rockaway neighborhood grief but also multiplying the investigators chores a hundred fold.
 
ewr757
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:15 am

>>The video of that pristine vert stab is really troubling, though.<<

That is very interesting as well Dauphine. I cannot help but notice the small amount of damage to the bottom of the vertical stabilizer where it attaches to the fuselage.

And the rudder, gone. Looked like the attachment brackets still in place.
 
Guest

RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:18 am

I'm not an expert, but I did notice that immediatley as well. Talk about cold shivers.
 
prebennorholm
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:18 am

I don't think that the A300/A310 have a wet fin.

But the clean cut: The A300-600 (and A310) fin is mostly made of carbon fibre, while the fuselage is metal. That may explain the seemingly clean cut.

The investigators must look at the bolts or main spar of the fin and such.

It is also hard to believe that adhesive bonding in general should be at fault. The A300 has flown with that for 27 years now, and it would show up at inspections of old planes first. This one wasn't that old.

Also adhesive bonding is no new technique. It has been used on some military planes for 45 years. I think the SAAB J35 Draken was one of the first planes to use it. A Mach 2 fighter of 1955 vintage.

Regards, Preben Norholm
Always keep your number of landings equal to your number of take-offs
 
Gregg
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 10:35 am

One thing many people are missing... The forces on a plane going 250 knots at sea level are probably higher then one cruising at 40,000 feet at cruise. I think something happend, then plane got a slightly sideways. The forces caused the tail to come off.

 
aa737
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 11:06 am

If the tailfin fell off, for what ever reason, could the wake turbulence of the JAL 744 ahead been the cause of the AA plane nose diving into the ground? Could the wake turbulence of a 744 be strong enough to flip a widebody A300?
 
spacecadet
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 12:40 pm

In the NTSB briefing tonight, they commented that two pilots on other airplanes saw the crash and said it went into a spin before hitting the ground. I could imagine a spin under max power with no tail fin could put some pretty high loads on the aircraft structure. Potentially could sheer some parts off, including the engines.

EWR757: I believe they found the rudder in the bay as well. I heard this on the news and I did see pictures yesterday which at the time were described as "wing parts" but looked to me like the rudder. It was in two pieces from what I saw and was laying on the deck of a boat in the pictures. I don't know if the break happened at impact with the water or before.

Another snippet of info for those wondering about video - the NTSB said tonight that they had a tape of the plane taking off, but that once the landing gear is retracted the plane goes out of view. They said all appeared normal up to that point. I am a little surprised there's no home video of the crash myself, given that most people seemed to have some audible warning of the impending crash and there's a huge population in the area. As for an airport-cam, it would have had to be at just the right angle, and maybe there just isn't one looking in that direction.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
Notar520AC
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 12:58 pm

I heard something about an engine failure...?
BMW - The Ultimate Driving Machine
 
Guillermo
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 1:27 pm

This aircraft (N14053 if I am not wrong) suffered severe clear air turbulence (passengers injured) near PR on 11/28/94 (FAA 19941128043499C incident report). Can this fact be related with tail separation due to excessive fatigue or weakness of the joint?
Regards,
 
POSITIVE RATE
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 1:38 pm

What if one of the thrust reversers deployed on one engine only??? This would certainly produce enough force to rip an engine off, rip the tailplane off and rip the vertical stabiliser off. That is how the Lauda 767 broke up in sequence within about 4-5 seconds of deployment. At such a low altitude the pilot would have had slim chance of recovering from this situation and the plane would break up!
 
spacecadet
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 4:30 pm

Positive rate: That's not how the Lauda Air crash happened. What happened was the reverser deployed, causing increased drag on that wing, which stalled and initiated a high-speed, spinning dive. The breakup occured not 4-5 seconds after deployment, but in fact something like a minute afterwards when the plane came close to breaking the sound barrier on its way down. The NTSB concluded that the initial reverser deployment was recoverable if the pilot had initiated immediate corrective measures, but they were not trained for that. Now, pilots are trained for that.

The accident report is available online, if you want to read it. I read it at aviation-safety.net, but I can't get in to their site the last few days.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
T prop
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 6:46 pm

I think Space cadets is theory is the most plausible here so far.
By the pictures shown on the news, it appears that the fasteners securing the vertical stabiliser to the fuselage may have failed. What could cause the vertical to depart the aircraft, flutter maybe? That may explain the 'rattle' sound, but if so what started it? One thing I noticed in the pictures of the vertical is that the rudder is completely gone.

Here's an interesting article on flutter. http://www.airspacemag.com/asm/mag/supp/fm01/Hammer.html

T prop.
 
mika
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 6:56 pm

I'm guessing that the tail section seperated from the aircraft. The rattling that was heard on the CVR was probably the fuse shaking like crazy due to the fact that there wasn't a tail attached to the aircraft to give it stability. All of that shaking may have hit a resonant frequency that caused the engine pylons to fail. This explains why both engines seemed to seperate before impact.


i believe in this one.
 
chiawei
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 7:36 pm

I also believe that it has to be similar to lauda air accident.

1. Assume that AA587 was flying close to its max 250knots below 10,000 feet. This is similar to be flying at 0.85 mach cruise at 41,000 feet. As the speed of Airflow relative to the plane is similar. Hence the force that the air exert on the plane is similar.

2. NTSB did say that engine appears to have no failure, but did not say if the reverse thrust was deployed.

3. Given that the CVR reported rattles at 120 sec. And the flight time was 160 seconds (right??). It would be very possible that following happened.
Turbulence of somekind->upset of the engine--> somehow triger the reverse thrust --> complete loss of control
 
Pilot1113
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 9:00 pm

>>Can you achieve thrust loads on the engines with
>>the throttles that would cause the engines to come
>>off? I'm fairly certain you can't.

In normal, everyday, flight I'd agree with you. However, when you increase to maximum thrust you're adding to the load of pylons and they're designed to take it.

Now, throw in the fact that the plane was yawing about wildly (basically snapping from left to right repeadily) it's not too difficult to see how maximum could be a causal factor in the engines breaking loose.

- Neil Harrison
 
Cyberflyer
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RE: AA587 - Tail Separation Initiated Breakup?

Wed Nov 14, 2001 11:53 pm

I think it was sabotage. None of this makes sense. The tail of the plane is too pristine-leading me to believe that somone got "to it". You never, ever see a clean break such as it is.

While wake turbulence is a possibility you would need much different weather conditions in terms of vortices. Rotar winds can be eliminetd becuase they roll off mountains and no mountains in sight.
 
VS744
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RE: AA587 - Tail Separation Initiated Breakup?

Thu Nov 15, 2001 12:00 am

How would someone "get to it"

wouldnt you require access behind the rear toilets on the -300 to do this?
 
XXXX10
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RE: AA587 - Engine Indication

Thu Nov 15, 2001 12:03 am

I read an ntsb report about an AA A300 that suffered an engine fire (I think out of MIA) and for some reason the warning failed so the pilots didn't realise that it was still on fire

Could an uniagnosed engine fire cause the engine to fall off

Just a theory
 
Rhino4ever
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RE: AA587 - Tail Separation Initiated Breakup?

Thu Nov 15, 2001 12:28 am

Has anyone found out why this flight had an hour and 15 minute maintenance delay at JFK?
 
Braniff727
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RE: AA587 - Tail Separation Initiated Breakup?

Thu Nov 15, 2001 12:35 am

One thing that I thinkis interesting is on the CVR the NTSB reported hearing the First Officer asking for "full power" seconds before the crash.

That, to me (not a pilot) that the engines were still operating. I would think the crew would know if they had lost an engine. I think that also could discount the reverse thrust theory as well.

Someone pointed out that this particular aircraft was involved in heavy turbulence in '94 and this could be an effect from that. I would say that is probably not the case as this aircraft went through a D check in '99.

The only other thing I can think of besides the tail coming off on it's own would be some sort of explosive decompression in the aft cabin, but I would think that would be audible on the CVR.
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