vertical stabilizer AA 587
 

http://us.news2.yimg.com/us.yimg.com...sh_nydd101.jpg

With apologies in advance to CaptPPRune who closed the previous thread on this crash, I thought this picture of the vertical stabilizer as retrieved from Jamaica Bay will be of interest to PPrune members. Jamaica Bay is between JFK and the crash site.

[ 12 November 2001: Message edited for typos by: SaturnV ]

[ 12 November 2001: Message edited by: SaturnV ]

http://www.aviationnow.com/avnow/new...s/raa41112.xml

This is the URL to the Aviationnow.com website. Looks pretty factual.

[ 13 November 2001: Message edited by: G.Khan ]

[ 13 November 2001: Message edited by: G.Khan ]

Does anyone know if there was any debris found on the departure runway after AA 587 become airborne ?

Most unusual debris pattern. It's difficult to imagine how an apparent uncontained engine failure might cause the vertical stabilizer to separate. (One of the engines found at the Texaco station had a large hole in the side of the cowling).

Agreed glueball... that picture is pretty worrying, possibly the most telling I've seen so far today. I can't see any trace of impact, tearing, or twisting... the tail looks almost as if it had just been unbolted. Loss of stabilizer -> total loss of control -> overstress -> breakup maybe? I can't conceive of any other scenario that would leave the tail so far from the main impact, apparently cleanly removed, with no obvious sign of damage.

Hopefully we'll know pretty quickly, whatever it was it must have been an impossible situation for the crew... RIP folks.

[ 13 November 2001: Message edited by: Ranger One ]

Without wanting to contribute in any way to the theorists I have to agree with Ranger One's assesment, very strange. My deepest condolences to the family members of the Crew and Passengers, may they rest in peace.

I recall that in the Mid 1970s a C-141 crashed after straying into a thunderstorm in England. The aircraft had rolled into 30 degrees of right bank in an effort to escape the thunderstorm, adding to the stress on the airframe already induced by the storm. At the crash site, number 4 engine and the vertical stabilizer were found together in an open field, hundreds of yards away from the main wreckage. That showed a historical correlation between engine separation and either stress on the vertical stablizer, or perhaps the engine actually striking the vertical stabilizer as it separated from the wing during. Of course, weather was no factor in the AA crash.

Global One
A rather unlikely event. A power plant would not be striking the vertical stab, not even the horizontal after a separation. Looking at the picture, it does seem to be a clear "cut", as Ranger One has mentioned, "un-riveted" almost. I can't come up with any plausible scenario causing such a separation myself either. In any case the vertical stab being separated in such way, found in bay can't have anything to do with a possible uncontained blade separation.

Beg to differ on the engine failure/tail theory. When the AA DC10 that lost an engine at Chicago in 1979, the engine flew over the wing and just missed the DC10's tail. In this case the blade failure may have been so severe that it caused the engine to separate and at that angle of attack after take-off the engine would have likely ripped off and over the wing. It may have then struck the tail a glancing blow, with various results.

Golf
Would it not be more likely that the Vertical stab together with the empennage be found in the bay if the engine would have struck the tail?
If indeed the engine came loos at the pylons but be otherwise still intact the DC10 scenario seems plausible. However, in this case, first reports state that the power plant suffered an uncontained blade separation literally shredding its interior. In my opinion, this would present a different outcome of the engine trajectory.

...except, from the photo, the tail appears TOTALLY undamaged (except for the missing rudder!).

My sincere condolences to all those involved in yet another tragedy.

Question: Is the A check (performed on this a/c on Sunday) of any relevance ??

Much as I hate to speculate about the manner of a fatal accident such as this I would just like to ask any driver of a large twin the following:

Catostrophic engine failure at take-off power + no rudder (according to above photo)= what?

I accept we don't know when the rudder separated but if it was while airborne ( engine debris? ) they would'nt have a prayer.

Incidently we can't see if there is damage to the other side of the H/Stabilizer.

R.I.P

[ 14 November 2001: Message edited by: westman ]

This picture*, which is not as good a perspective as pictures shown on television, is of the fan section of one engine. This engine is located in the yard of a house on 127th St. Another picture of an engine and cowling (or part of this engine?) posted on the closed thread is that of the engine that landed at a petrol station on 129th St. The engine in the yard is slightly to the left of the flight path; the engine at the station is slightly to the right. The main portion of the aircraft impacted at 131st St. (The streets rise in number going from east to west.) The vertical stabilizer was retrieved from the water several hundred yards or more to the northeast from where these engine parts impacted.

Radar trace information is as follows:
9:14.34 takeoff
9:15.02 1300 feet, 200 mph
9:15.36 "plane begins to climb more rapidly"
9:16.01 2800 feet, 306 mph (last trace)

(The above information courtesy of the New York Times.)

http://dailynews.yahoo.com/h/p/nm/20.../mdf84430.html

* The image will not post for some reason. Here is the URL address: http://dailynews.yahoo.com/h/p/nm/20011113/ts/mdf84430. html

[ 13 November 2001: Message edited by: SaturnV ]

[ 13 November 2001: Message edited by: SaturnV ]

the mayor said that a wing was also in the water north of the main debries, wouldnt that have had to depart the aircraft in flight too?

what are the coast guard saying, they must have had a cutter in jamaica bay, seemed to have no trouble finding wing and vertical stabiliser

incidently does anyone know anything about the investigation into the cause of the A310 crash off of the ivory coast in jan 2000. we are coming up for 2 years since that incident with no word.

If the wing was found in the bay also couldn't it have been this that struck the tail , correct the photo does make the tail look undamaged but the rudder is missing , could something striking just the rudder cause the whole tail to be torn off , also we don't know what the damage was to the rear of the aircraft below the tail , apparantly it nose dived into the ground suggesting maybe the whole of the tail may have been damaged.
Deepest sympathy to all the relatives

Reports of a wing having come off are apparently in error, with the vertical stabilizer being mistaken for a wing. Jamaica Bay is relatively shallow and I'm quite sure a wing would be easily spotted and recovered by now.

There are edge-on pictures of the stabilizer, and both sides look smooth and relatively undamaged.

Sorry to ask for simple explanation - but could someone tell me in layman's terms what is the significance of the vertical stabliser being detached so cleanly - what does this suggest about the reasons for the crash. Pardon my ignorance

Latest - if the vertical stabiliser had been hit I (as non-engineer, I hasten to add) would expect there to be evidence of impact damage from whatever had struck it (such as an engine). Also, again as a non-engineer, I mught expect there to be tearing and buckling of the surface where it had ripped free. However, I do not know how the tail surface is attached to the fuselage and so it may be feasible that high enough stress could cause the fasteners (bolt, rivets etc.) to fail and if the vertical stabiliser is strong enough this may leave little or no damage on the stabiliser itself.

Bear in mind that an aeroplane that suffers catastrophic failures may display evidence of damage that simply does not look feasible to the non-engineer but which is actually quite expected as far as the accident investigators are concerned.

So, in answer to your question, I feel that there is non significance yet - the separation has to be taken as one part of a complex sequence of events which will require much more information (such as ADR and CVR info) to explain.

thank you very much - that really helps me. I'm trying to unravel all the conflicting reports and scraps of information that are floating around. Much appreciated. xx

Re the C-141 accident - actuallytwo C-141's were lost within minutes or a few hours of each other, the second in Sonderstrom. Both 'accidents' had very similiar wing separations. Both aircraft parked side-by-side on the ramp at McGuire AFB before departures. One accident investigator I spoke with swears these were not mechanicl failures. Re AA 587, I don't think I've ever heard the NTSB make any comments within the first 24 hours of an accident ruling anything out. Why this time?

When trying to work back from ground wreckage patterns to establish the order of break-up in flight, it has to be remembered that something relatively light and very aerodynamic (like a vertical stabiliser) can slow down very quickly after it leaves the aircraft and can also “fly” some distance in any direction depending on how it rotates as it falls. On the other hand a heavy small mass (like an engine) will behave very differently. Lockerbie gave several instances of this. Expert interpretation of debris fields way beyond plain common sense is required.

With so many bits being recovered I am sure the investigation will be able to establish a likely series of events more quickly than in some other tragedies.

But all of the bits of the jigsaw must fit – not just some of them – in order to get the perfect picture and patience will be required by LATEST and others. A holding piece about such investigation issues rather than an attempt at a quick answer would go down very well with the professionals and, I suspect, a lot of the public. Might not be easy to convert the news editor to such an approach though.

Could the fin have been detatched by yaw or side-slip forces? Alternativly, could the loss of the fin cause the seperation of an engine? Cause or effect?

E-cam I seriously doubt the likelihood of either of your propositions. The rudder/stabiliser is designed to be used to keep the aeroplane straight if an engine fails or separates, and should therefore be up to the job.

If the engine mountings can secure the engine at full power, then a bit of yaw is highly unlikely to cause it to separate.

As both John Farley and I have said, we will have to wait.

John - I loved that photo of you hovering a Harrier with the gear up - it looked really smooth. Did you ever work with Mike Laughlin, RAF TP on the Harrier develpoment? He flew the P1127 quite a bit and said it scared the you-know-what out of him!

If a high power engine is stopped rapidly (say by swallowing a line of migrating Snow Geese) then the resultant rapid yaw, added to the violent torque may well exceed the fuse pin design strength - and lead to a detached engine striking the vertical fin and carrying it away.

Takes a bit of imagination, but cannot think of any other chain of events that would fit.

John Farley:

Well said. The only reason I got into this was the 'obsession' in local media here in New York with the 'engine fell off and it crashed' theory (if one can dignify that with the term 'theory').

E cam:

That's what I found worrying about the image - there is no evidence whatever of damage to the stab. One might expect considerable impact damage if another part had hit it, causing the separation. If it failed from aerodynamic forces, one might expect twisting, buckling, skin damage, or midspan failure.

None of this is seen, it is *as if* the loss of the stab was *perhaps* the first stage in the accident, with the engine separation etc. occuring as a consequence of the overstress and breakup that would follow.

LATEST: *everything* you read here - my own posts NOT excluded - is worth precisely what you've paid for it. Just don't make the 'engine failed/fell off' assumption and go with it - this needs MUCH more investigation.

Ranger One - point taken - yes its all a bit rudimentary the press speculation at the moment.

Dagger Dirk - I read on the NBC and CBS websites that there were reports of very high bird activity in the area prior to the plane taking off. Maybe that fits with what you said ?

Here is another image of a piece of wreckage that fell from the plane into a parking lot, taken from a BBC article. It too looks like it came from some kind of aerodynamic failure, rather than being dislodged by impact from a stray engine, or stray engine part. What part of the plane is it?

http://news.bbc.co.uk/olmedia/165000...ar300megan.jpg

This is the most perplexing crash. At first I thought that this crash may have been a replica of the American Airlines DC10 crash at Chicago, where the engine pylon failed because of improper pylon attachment. That engine rotated over the wing and hit the top of the wing, causing all the hydraulic problems that made the plane uncontrollable.

In this case I first thought that the engine may have broken off and flipped up over the wing with sufficient force to cause the wing to fail, or to somehow subsequently hit the tail assembly.

But the problem with this kind of conjecture is that both the engines appear to be near the fuselage on the ground, while the nearly undamaged stabiliser appears to have left the aircraft at some point in flight before the subsequent trajectory of the debris found on land.

The pictures of the engine at the service station are also unusual, in that to my untrained eye the only damage to that engine is ground impact damage. Did it also come off because of aerodynamic forces rather than because of some internal failure?

I too am of the mind that there may be some some structural cause of this crash other than engine failure. Where is the rest of the rudder? It should also be out in Jamaica Bay somewhere, should it not?

I cant help feeling that things probably happened the other way round. JAL123 (1985) flew (erratically) for over half an hour without a tail fin.

I'm no big engineer, but if the engine seperated through some sort of fatigue or shock surely the drag on that wing could cause severe shock loading on the fin also, could this also be enough to rip off the rudder from the fin?

Could the loss of hydraulics and the fin under severe yaw put the aircraft in to an uncontrolable dive more quickly than normal, maybe ripping the other engine (still under heavy thrust) fom its mount?

Thoughts and prayers are with all the families involved.

McGinty.

The photograph shows one of the wingtips of the airbus. It's impossible (for a non-expert like myself!) to say whether it is from the port or starboard side, as it is more or less symmetrical about the plane of the wing. Also, the port/starboard wingtip indicator seems to be broken/missing, so unforunately no clue can be gleaned from that either.

The top of the fin (Vertical Stab.) is generally where the FDR is located on most aircraft.

Mayor Guilianni and others have stated thet CVR was recovered, but NOT the FDR, which makes no sense to me.

Can anyone tell me where the FDR on this aircraft is located?

I think you'll find the FDR is located on most modern aircraft behind the pressure bulkhead, never yet seen one on the vertical fin, but am willing to accept that some may have it there :)

Actually I'm reluctant to speculate about the possible cause. But such an inflight break-up reminds me of the Lauda Air 767, on which the thrust-reverser suddenly deployed.

Buck Rogers is probably on the right track:

a. Stbd engine swallows a number of large birds and stops very suddenly due to severe rotational imbalance.

b. Side-Torque generated by this seizure slews that engine and its fuse-pin, upon reaching its design limit, lets go. Engine departs cleanly.

c. With the other engine under high power, and now due to great weight, lift and drag disparities, aircraft commences severe yaw (and roll and pitchdown/IAS increase) - imposing side-forces beyond design limit upon the vertical fin (which separates cleanly)

d. Aircraft "winds up" in its spiral dive with rapidly increasing asymmetric g and roll-rate - causing other engine to also depart due to excessive lateral loads on remaining engine pylon.

The key here is the design strength limits of fuse pins and vertical fins, once subjected to severe out-of-axis forces. Not sure why rudder would have detached (if it did). Winglets may have been torn off due to the same lateral aerodynamic load exceedances.

Absolutely ridiculous speculation!!

Time to close this thread as well

Gentlemen: Speculation is more interesting when it is consistent with the currently-known facts. The vertical stab was in the drink, roughly along the flight path and between JFK and the spots where the engines landed. The main part of the a/c landed on 133rd st; the two engines wound up at 128th and 129th streets, respectively.

This would seem to indicate a strong likelihood that the fin separated from the craft before the engines did.

Source for engine locations: NY Daily News

As for an engine seizeure causing seperation........ I doubt it. We practice for this in the sim. The aircraft will fly. Only difference is we shut it down earlier than a "normal" engine failure. Lots of vibration.......YES. Lots of noise..YES! However I cannot see how this alone can, or will cause seperation. However I MAY be wrong!
I don't know what caused this accident, no-one does. I do not think that speculation, however well informed it may be, helps the situation!! Lets leave that to the people who are experienced in that field, and have the evidence at hand!
Eff Oh.

wideman

Good point about speculation needing to be connected with emerging facts.

The facts seem to support a lot of bits coming off the aircraft in flight, way beyond what one might expect with any simple engine failure or even an engine separation that caused other damge (as at Chicago)

JBravo is quite in accord with the facts - an inflight reverse on one side at high power would cause a much higher level of sidslip than any single engine operating case

As a first event to trigger the rest it seems top of the frame

Given that American Airlines prefer to polish their aircraft, can we assune the tailfin of the A-300 is plastic ie. carbon fibre or of some sort of aramid construction?
(in the photo it appears to be painted light grey). If this is the case perhaps it has some bearing on the possible chain of events leading up to this tragic accident. Perhaps may also explain its intact appearence as if its made of this stuff its effectively one big piece. Thoughts anyone? (apologies if its really made of aloominum!) maybe an AI employee knows.

Does anybody know how may hours/cycles were on the Airframe/Engines since the A check?