Flutter in Plane's Tail Eyed as Cause of Crash

New York Daily News ^ | 11/15/01 | RUSS BUETTNER

[KQQL]

"Flutter is the demon of all aviation,"

No , terrorism is the true evil of all aviation.
By the way the tail just doesn't fall off a 12 year old plane. (Flutter was probably casued by someone leaving the bolts loose on the tail )

[NoControllingLegalAuthority]

"He's got no rear-view mirror," Goelz said. "All he knows is that he has lost control of his aircraft."

This is an interesting point. Why not wire key surfaces with sensor wires so that any rupture or separation would be recorded on the Flight Data Recorder and displayed instantly in the cockpit?

[KQQL]

:)

[onyx]

Tin foil alert?

[John W]

OK,who had "flutter" in the pool?

[NY.SS-Bar9]

Flutter ! of course - FLUTTER.

How could I have been so blind. The answer was right there in front of me.

Silly me. I thought it was terrorism, then the engines, then birds, then wake turbulence, then old damage....

Of course flutter always causes an explosion visible from the ground too.....

[rambo316]

Hear this, Bullsh!t. Again, this is Bullsh!t. Like I just wrote to Joe Farah, over at WND, 9-11..., what about 11-12?This is just like Flight 800 in that the government doesn't want to report the truth because if they do, the masses would get hysterical. From hour one, almost 1/2 hour one, we heard that this is most likeky an accident and most likely not a terrorist act. C'mon, give me a break. The governor of NY, George Pataki, said that the pilot dropped the fuel over the water which turned out to be false, then we hear that there was a mechanical problem, or engine problem, they, NTSB, said that maybe some doves or birds flew in the engines and that made the tail and the engines fall off. Then they said that the engines were fine, now, it happened because the rudder flew off because of loose bolts or something like that, but it was most likely an accident and most likely not a terrorist act. BullTicky!!

[eno_]

Hey, I got some flutter in my sneakers, and now I can jam like Michael Jordan. Pretty good for a white guy. Damn that's good flutter. Personally, I was hoping someone would be dumb enough to try "exploding center fuel tank" to explain the loud bang and bright flash reported by eyewitnesses.

[dawn53]

Flutter could be the element that connects those two phenomena — though it would be the first time in aviation history, experts said.

And who's accusing whom of stretching to find an explanation?

[SC DOC]

I deal with atrial flutter, but have never heard of a tail flutter.

[DB]

"Flutter" is an oscillation in the system. An electronic feedback control problem for example could over correct back and forth increasing the oscillation to the point of structural failure. Resonances in structures with feedback systems are always difficult engineering problems. If one of the loop feedback design characteristics changes beyond what the system was designed for it can oscillate in a very severe destructive way. A severe oscillation could literally rip the engines from the plane causing what looked like an explosion from the ground. This is a fly by wire plane. A malfunctioning sensor in a critical feedback loop could cause destructive "flutter". The computer responds to bad information making the problem worse until the structure fails.

This is not nearly as far fetched as it may seem.

Just MHO...

[pops88]

My husband and I are both pilots. He has thousands of hours in jets. This just keeps getting funnier and funnier. Next it'll be a dinner service cart that got loose, rolled to the back and took the tail out. Oopps, maybe I shouldn't give them ideas.

[chainsaw]

This is a bunch of BS. Stall warnings are produced on some airplanes and are referred to as "stick shakers". They produce a flutter to warn the pilot his air speed is too low.

A Flutter. ??????????

[tarpon_bill]

Or get some of those popup add cameras. Then the pilot could see these control surfaces.

And best of all ... Maybe the popup ads would go away.

snooker

[mewzilla]

Well, at least this is a little more sophisticated that the flying frozen Butterball hypothesis. Gotta give'em points for trying. And, while they're at it, maybe they can explain why the 8 mi distance between the planes that was first reported has suddenly decreased to less than five? Or why the flight controllers would violate the time allowed between planes for take off (if in fact they did. Betcha the flight controllers get the blame now. Especially since, as federal workers, they CAN'T be sued.)

[Lion's Cub]

Of course, flutter doesn't explain this: Air Authorities Monitored Terrorist Threats After Downing Of Flight 587

[unending thunder]

Just did a Google "Flutter aircraft", big library on this, conferences, there are flutter engineers, who specialise in Aeroelasticity, even low cost PC Finite Element analysis programs.

Here's a definition ; Aerospace Magazine

Flutter is a phenomena which can lead to the catastrophic loss of an aircraft in flight. It needs to be addressed from initial design through flight test and certification. The earlier on in an aircraft program that a potential problem can be discovered, understood, and prevented ("fixed") the less money it will cost to implement the "fix". Fixes can include additional structure (weight penalty), and/or aerodynamic modifications (could result in lower aircraft performance which may lead to more fuel required to perform a mission, etc.).

Presumably, since they have been making these things for nearly 20 years, the appropriate analysis has been done and refined. If an object the size of the rudder "fluttered" sufficently to be ripped offf it would show internal /external damage?

I think it's the paint, probably to cut costs they got it at WalMart and Sam didn't tell them about it's special flutter properties. Maybe all the passengers were followers of Maharishi and doing some Yogic flying casuing synchronised flutter, bad Karma could do this to one of the strongest structures man makes.

[billorites]

Flutter is a high speed phenomena. Flight 587 was in a climb at relatively low airspeed.

[Movemout]

Composite structures are well understood but not as well understood as metal structures. I was involved in a project building a hypersonic airframe with all composite primary and secondary structures. Additionally, one of the propellant tanks (kerosene) was composite. We had several failures during the devlopment process resulting from design deficiencies and suffered from unanticipated failures during loads testing. This was state of the art application of what is known about composites. I can very easily envision techs applying a coating to a composite-metallic interface that was never intended, or positively prohibited, by design engineers and inadvertently causing a weakening of the the interface. There are other processes that maintenance techs might execute that could cause such a failure given the relative immaturity of working with composite materials. I do not discount any possibility in the shearing of the vertical stabilizer, especially given that the attach points were intact. The derision expressed by some respondents to this thread are unwarranted.