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Am I the only one who wants to know exactly who serviced and had access on the ground crew to that plane/engine on 11-11

Nope. You can bet the NTSB will look into it -- and if it smells funny, the FBI too.

and was the flight that crashed the first time it had been in the air since the ground crew worked on it ? No.

It is also unlikely that it was hit by a missile (a Stinger or Strela/Grail makes a very distinctive plume). Unlike most worried FReepers, I've seen 'em, and in New York City at 9:12 in the morning you are not going to miss 'em.

It is also unlikely that, as one concerned fellow suggested, a Muslim worker in the European Airbus plant sabotaged the plane in manufacture. It was built in 1988 and has been flying ever since, until yesterday's tragedy. I don't pretend to understand these Jihadis but he would have to be hell for patience. And... I dunno how you sabotage a plane to crack up 13 years down the road.

I suspected sabatoge on the ground from the first time I heard yesterday it had been serviced day before.

A mechanical error is also possible. It has happened before. So far all NTSB is trying to do is gather all the facts they can. The wreckage tells a story, the maintenance logs tell a story. Autopsies of the victims ensure that their last story will be told, if only in the privacy of the NTSB offices. Experts from Airbus, American Airlines, the engine designers and builders, the APA (pilot's union) and the government will be called in as needed. Crack aerodynamicists and metallurgists are on call, too.

NTSB will release many facts as quickly as possible, but they will take their time drawing conclusions. An accident like this usually takes a year to be a complete report available to the public. There are some facts that NTSB normally never releases, but these are ones that would not help the public understand the accident but instead merely invade the privacy of the victims and their families. Those things include autopsy photos, accident scene photos that show human remains, some parts of the autopsy reports, and the actual CVR tape (a transcript is prepared. In recent years, the transcripts have been censored under pressure from crew unions and Christian fundamentalists who are offended by salty language, but only non-pertinent information is edited out).

NTSB also controls the accident site with the help of local police. People aren't permitted to wander in, and journalists and lawyers (and their minions) are particularly guarded against, as both of these types have a record of mishandling evidence and disrespecting the deceased.

Finally, when the NTSB has all the evidence from the scene, they will release it to local authorities for clean-up. Meanwhile they will be reconstructing as much of the plane as necessary in a hangar somewhere. They build an armature and hang airplane parts on them. Engineers can tell by examining the parts which order they break up in. (Contrary to other statements, inflight breakups are not unknown. They are actually fairly common among small planes when the pilots fly them into really bad weather. There have also been a number of jetliner breakups, triggered sometimes by weather, loss of control, or malfunction).

When the NTSB has a large tranche of facts they will release it to the public and post it on the website (www.ntsb.gov). A number of groups of experts will look at the engines, the maintenance, the performance of the pilots (this is the "human factors group") and any other specialty factors in the disaster. When all the facts are in, all the reports are posted, and the IIC (Investigator In Charge) is ready to propose a probable cause for the investigation, NTSB will hold a public hearing in a city near the accident. The experts will be heard from (and disagreements can be aired. You too can attend this hearing and speak).

Finally the hearing will result in a Statement of Probable Cause. Not the cautious name for what is essentially a scientific, not a judicial, process. If they can't figure it out they don't issue a probable cause. Yeah, this really happens. Sometimes they come back and revisit an old accident in the light of new evidence, too.

The purpose of the investigation is to examine causative factors in an accident (usually there is a chain of unfortunate circumstances leading to the disaster) and to make recommendations that may prevent a repeat. The NTSB report may not be used in litigation or in criminal proceedings, which is why when crime is suspected the FBI takes charge of the scene. Right now, FBI agents are shadowing NTSB and NTSB is willing to chop the investigation to FBI if evidence of crime is found. Honestly, they are keeping an open mind.

FBI and NTSB have worked hard at working together since the TWA 800 disaster. FBI led that investigation because there was no obvious way the plane could have exploded like that... when the fuel tank explosion was found to be theoretically possible, and no credible evidence of crime was found, NTSB got the investigation back, in front of a public that was now unready to believe anything but the FBI's discredited bomb and missile theories! So you have the ongoing ravings about bombs and missiles in that case.

There are times I find myself disagreeing with NTSB, usually in lesser-known accidents involving small planes, or airline accidents that did not have many casualties. (These accidents usually get a lot fewer resources than a headline-grabbing disaster). But I have never been able to fault their methods or their integrity.

Please remember that the first time a bomb was ever used to down an aircraft, it was the NTSB's forerunner's investigation that determined this fact and provided the evidence vital to the FBI's case. If there was a bomb, or a missile, it will be found.

What else could it be? This is absolutely speculation at this point, but I would say in order:

some maintenance error. Several FReepers have already mentioned American's loss of a DC-10 in Chicago in 1989 when an engine came off because mechanics had damaged an engine pylon. JAL 46E, a 747 freighter from Anchorage, suffered a similar pylon failure when the engine went paws-up, but was able to land safely, in 1993. (JAL 46E's engine failure was caused by a flaw in a part of the engine. Before the government was done, all engine parts cast from that batch of metal -- and yes, the paper trail on airline parts goes all the way back to raw materials -- had to be tested and/or scrapped).
uncontained engine failure interfering with flight controls (in the A300, fly-by-wire). This is of course the cause of the "impossible" United 232 accident in Sioux City, IA.
uncommanded reverser deployment. (This happened on a Lauda Air 767 and the cause has never been 100% certain -- it could have been one of three things and all three were ordered to be changed)
Flight control failure. Some failures could theoretically cause control surfaces to move quickly enough to fail the structure.
sabotage. No evidence for or against yet, so we can't rule it out. But sabotaging a jet is not easy.

Common accident causes it probably isn't, and why not:

Primary pilot error. It is hard to think of a way the crew could have caused this. They might have done something to make it worse, I dunno, but for now let's give them the benefit of the doubt.
Weather. While I know of a 707 and a DC-9 that were returned to kit form by bad weather, one flew into a mountain wave and one flew into a thunderstorm. I was in New York and it was a great day to fly -- no such bad weather was present.
A fuel problem. Whatever they had on board sure did burn, and where they were coming from all it could have been is jet fuel.
Cargo door or pressurisation failure. The airplane got to 2,800 feet above sea level, max. There would not have been any pressure differential between the plane and the outside yet. (This has caused a number of tragic earth-plane encounters).
A missile. Again, someone would have seen it. If it was, though, it will be unmistakeable. Weapons and bombs damage things differently than crashes do.
Bird strike. This initially popular idea seems to be contraindicated by lack of bird remains in the tail and engine wreckage. Once again, further evidence could cause this position to change.

But all this is speculation. Let's let the pros gather the facts and then see what they do with them. Let's not be flustered by journalists, who know absolute squatto about aviation, and conspiracy theorists, who know only those facts that advance their theory (whether real or not) and discard the ones that don't fit. Compare the approach of the FBI, who were willing to let their TWA 800 theories go when the evidence did not support them, and the conspiracy crowd, who massage "evidence" to support more and more farfetched ideas.

Sorry for this long post. Hope that FReepers find it helpful. I know a bit about this stuff, and am not taking a position on the cause of this tragedy until I know more facts.

d.o.l.

Criminal Number 18F

You didn't list "bomb" and you forgot to take uncontained engine failure off the list of possibles.

I thought sabotage was last on the list, and bomb was #1, due to the witness who said she saw a bright flash. Now that it appears certain the fash was NOT caused by the engine blowing up... ? But then why did the vertical stabilizer come off so cleanly?

Good informative post. Between sabotage or mechanical failure or some other cause, it could go either way with me.

But sabotaging a jet is not easy.

Without going into too much detail, could you please elaborate?

That was a well written post as to what the NTSB does during an accident investigation. Having been a private pilot for many years I was very grateful that Clinton was never able to put the FAA in charge of avation crash investigation like he wanted too. I guess he felt he had to do this because of soo many of his friends passing on by way of aircraft accidents. If in the end the NTSB is unable to conclusivly determine the cause of the crash, I'm with everyone here, we blame it on the Taliban.