Posted on 06/01/2004 1:18:12 PM PDT by Boot Hill
Edited on 07/12/2004 3:42:14 PM PDT by Jim Robinson. [history]
WASHINGTON, DC, May. 29 (UPI) -- An investigation into the November 2001 crash of an Airbus A-300-600 in New York has found an unrelated potentially lethal design flaw, the New York Times reports.
The newspaper says the National Transportation Safety Board does not believe that problems with the rudder control system caused the crash of American Airlines Flight 287 [should be: 587]. The plane came down shortly after taking off from Kennedy International Airport en route to the Dominican Republic, killing all 260 people on the plane and five on the ground.
(Excerpt) Read more at washingtontimes.com ...
Crash probe uncovers flaw in Airbus jet
--Boot Hill
That's one tall plane.
Yes, the rudder tends to stick when in proximity to a shoe bomb.
I was at LaGuardia waiting to fly home to AZ when I saw that crash on the TV... Went right to the bar and ordered a drink.
Only problem with that theory is that there is ZERO post-crash forensics that supports that possibility.
--Boot Hill
That's one tall plane.
Not nearly as tall as it *used* to be, apparently...
Someone smack this reporter and editor until they learn the difference between "altitude" and "height".
He and others believe that Airbus cannot correct the flaw without a major redesign. Planes already in service cannot be retrofitted with the correction.
ROFL
Shh, don't interrupt a conspiracy theorist with facts, it just confuses them.
Since the A-300 is a fly-by-wire, i.e. a computer translates an input from the yoke and pedals to an electrical signal to an actuator, this would simply be a programming change.
Just like with every crash of an Airbus built aircraft, Airbus will not accept blame and will turn around and blame the pilots and airline.
Oh, I don't really think that's what brought it down. But I enjoy suggesting it, because of how officials always downplay or reject the possibility of terrorism before the fires are even out.
See #13.
The vertical stabalizer came off.
After loss of rudder control, it went into a spin, the spin made it shed parts all over the streets below, and crash.
Rudder control is what keeps an airplane from spinning. (invented by the Wright Brothers to keep their airplane from spinning.)
Composite/carbon fiber delamination?
Not quite. Part of the equation is the rate of response of the actuator and this could be related to air pressure on the airfoil as well as it's structural requirments.
There may not be a solution that meets NTSB requirements as well as the stability and structural requirements of the rudder.
Exactly
Actually the A300 and its smaller sister the A310 are not fly-by-wire. The A320 family (A318/319/320/321), A330-200/300, 340-200/300/500/600, and the new A380-800 are FBW.
I don't think the delamination was the primary cause -- it was a result of the design defect, and resulted in the failure of the vertical tail and subsequent loss of the aircraft.
Reading between the lines, I think this is what happened during the flight: the aircraft flew through a wind gust or wind shift that quickly increased the airspeed (relative to the wind) to a level above that allowed for the low speed rudder setting.
For example (and I don't know the exact numbers here), at airspeeds below say 180 KIAS, the allowable rudder deflection might be 30 degrees. Above say 180 KIAS, the allowable rudder deflection might be 15 degrees. At higher airspeeds, say 250 KIAS, the allowable rudder deflection might be 10 degrees. Since rudder force is proportional to the square of the velocity, the maximum allowable deflection at a given airspeed is set so as to provide sufficient yawing moment but not allow excessive yawing moment.
If the airplane was flying at say 175 KIAS and the pilot moved to maximum deflection of 30 degrees, the flight control system would command 30 degrees and the vertical tail and rudder would be below the maximum allowable loads. If a wind shift occurred during or after this rudder deflection, and the airspeed increased to say 250 knots, the rudder, which is still deflected at 30 degrees, would cause a high yawing moment and the load on the vertical tail might be above the allowable maximum load. The pilot might try to compensate by turning the rudder in the opposite direction which might exacerbate the flight upset. This might cause failure of the rudder and departure of the rudder from the aircraft and subsequent aircraft crash.
I postulated this theory at work (an aircraft component manufacturer - I'm an aerodynamics engineer) and on one of the crash boards after the crash. It's good to see it proven out.
The A-300 I worked on 15 years ago was (former Easter Airlines plane). The only cables on the whole aircraft were to either the fire bottles or the fuel shut off (maybe both, can't remember).
http://www.airbus.com/media/fly_by.asp
Fly-by-wire is an electronically managed flight control system, which uses computers to make aircraft easier to handle while further enhancing safety. First introduced on a commercial jetliner on the Airbus A320 in 1988, it has become an industry standard.
Next you'll be telling us that TWA 800 wasn't brought down by a shoulder fired SAM from a speedboat out in Long Island Sound.
Or was it an Aegis training round (inert warhead)?
For some reason, that strikes me as a very funny phrase to describe the event. Is this standard aerodynamics jargon that I'm just not used to seeing?
I just got off an A300 from San Juan about 3 hours ago. I am glad I read this now and not before leaving. I would have ordered a whole bottle of booze.
A B-52 lost 80% of its vertical stabilizer in flight due to turbulence -- and the pilot flew it to a safe landing. I've seen the pics.
As I recall, the problem seemed to be that the rudder controls required a lot of force on the ground or at very low speeds. In flight, they were much more responsive. The co-pilot was not familar with the Airbus. It was his responsibility to operate the rudder foot pedals and to perform pre-flight checks on them. One theory was that when performing the pre-flight check-out he came to believe that the rudder required a lot of force. In flight, when he needed to operate the rudder he literally stepped on the control pedal and when the rudder over responded he jammed them in the opposite direction. It was classic example of an underdamped control system "hunting". The loop gain was too high and the time delay too long. After reading about the Gimli Glider, I sure wouldn't want to be in an Airbus when someone is attempting a dead stick landing.
And I am telling you that what I know ans daw (in my previous career, I was an aviation electrician and electronics tech). There are no mechanical connections between the yoke and the flight controls on an A-300. The A-300 has triple redundant flight control computers.
I suspect that we have a slight terminology problem here. The A-300 had flight control computers, but they were large and heavy and primitive by today's standards and, if I am not mistaken, analog computers vs. the digital computers of the A-320.
As I have implied, I have helped disassemble, inspect and rebuild several A-300's and dozens of 707's and DC-8's and 737's and 727's. There are only about 4 cables on an A-300.
How much of the plane is still in the bay?
Not the A310. It was conventional controls. A320s are FBW. However, if you think it was a shoe bomb, or a baggage bomb, an FBW plane would be much harder to take out, since the fiber optics and multiply redundant and the redundant links are run physically far apart.
Yes, in a nutshell. A very stupid location for composite materials.
Yes, losing the vert stab by itself should not have caused immediate loss of control.
More likely, the very stab and engines left for a common reason: High aerodynamic load on surfaces that never meant to fly sideways at 300+ kts. I.e.: loss of control first, then loss of large surfaces. Bomb or bad design, who knows?
Since Flight 800, since OKC and Waco, since Clinton was exonerated, who can trust the beltway and judges from of the beltway? Big black holes in every case they associate with. No "fully informed juries" after they lacebug the truth.
No dispute with any of this, but I would suggest (as I often do) that it was not at all smart to depend on composite materials to bear that load. Tests or no tests, that piece should have been metal all around. If weight was the issue, toss a hunk of titanium in there, but don't bet the farm on fabric and glue, right?
When and where?
And, as someone has already pointed out, there are no forensics indicating explosive material.
The bay is murky, muddy and black and full of trash. How much of the plane was recovered?
Because conspiracists are everywhere, especially on conservative websites.
Many of these people are disciples of Michael Rivero, formerly of this website, and head-conspiracist-in-chief.
--Boot Hill
You said that Al Qaeda claimed the hit.
When and where did they do this?
Circumstances provide the honest suspicions -- just as they do at any murder scene. Many a man is on the death row, due only to circumstances -- is that too part of the conspriracy mindset you speak of?
It was in last weeks news, or are you coy?
I noticed that about FR, especially whenever someone has to drag up TWA 800 and start new conspiracy theory threads. I think my first or second post here was debunking much of the TWA 800 conspiracy and several people tried to have me banned for being a troll. Needless to say I'm still here.
I didn't see it. At all.
There's no evidence that al-Qaeda had anything to do with this crash, regardless of what some operative says.
And the tail of your 777 is made out of...??? J
"You can tell it's swell, it's Matel!"
--Boot Hill
I think there's a collective delusional mania that has affected otherwise sane posters when it comes to TWA 800. I stopped posting or reading those threads because they were pure fantasy.
Someone will dredge up one, every once in a while, with another bizarre theory to add to the already bizarre theories posted five years ago.
Things were a lot worse before Jim banned Michael Rivero four years ago.
Did you know that JFK Jr's plane was blown up by a bomb under the wing?
Yes I did. It was planted by the same person who shot down TWA 800 with a Stinger missile.
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