Was there not some question on the 'turn around'? What was the reason for this not being clear? I'm a bit lost on this.

I agree completely, and I can offer no clue as to the event or events. That is the only thing that makes me still lean toward a human intervention. I can't offer any insights to a cause of the failures but there are some possible insights as to where the plane may be and why it may be there.

They found the guy that bought the tickets. He's Iranian. But he contacted authorities when he heard the story. It doesn't sound like he's exactly trying to hide.

Why this route? I just don't see who stands to gain from attacking such a diverse route. I certainly don't see how an Iranian terror group would benefit.

To get the three Americans.

Trying to figure out the logic of terrorists is impossible.

Okay, new information (to me.)

After some deeper investigating, I found that the time the plane disappeared from radar (ATC) was actually ~1:22 a.m. but that the Airline wasn't informed, officially, until 2:41 a.m. That accounts for the hour and nineteen minute gap. With that information, I would dismiss my scenario, above, as a possibility. It appears that the course change and disappearance all occurred at about the same time.

I'm back on board with those who see a sudden, catastrophic event but I'm open to ideas as to high altitude disintegration or crash into the sea. It's still quite a mystery.

There are some interesting theories coming up. The best ones are supported by hard facts and aviation knowledge. And there has been a little overlap of those sources in the discussion.
Now - I THINK - that the passport issue might be overestimated by the public based on the other information brought up here. The passport problem is scary. But an explanation for the lack of communication while in the air still had me thinking of a hijacking. The pilots might be forced to stay off the comms or hijackers took control while directing the flight on new vectors once it is past ground radar - with simulated position data giving false vectors. Sophisticated and far fetched - but I had to throw my theory in the ring. I read too much Tom Clancy. I would be searching an area determined by last ground radar position and remaining fuel - a huge swath. Perhaps there are clues in the dis/continuity and background data (GPS type - satellites used) in the Avionics feed. I read this discussion expecting our aviation experts to have some answers - I think the smartest ones are holding their tongues.

FYI:

Input from my neighbor - a US Air pilot.

Asked him if there was a consensus amongst his peers and he said "No one knows anything other than what has thus far been reported. It's truly a mystery."

Then I asked for his opinion.

He said he's leaning toward some human related intervention. He also said the radar systems in that part of the world are a bit sketchy.....so the searchers may not even be searching in the right area(s).

He also said the planes have both homing devices which are activated when triggered by a certain G force level or hit by water. Also the black box gives off a beacon. But if those are down past a certain depth - they are not detectable.

He said we may never know what happened or we may find out soon...really no way of knowing how it will play out.

For how long can a plane be flown at "sea level" and would that show up on radar. If set into water at a low angle/height would it break up or just sink? In a steep angle dunk, the plane would break up...wouldn't it?

Sea level is very inefficient fuel-wise. It can be done but range will suffer a lot versus "at altitude" (iirc jet engines are usually optimized for FL360).

If an aircraft is slowed enough and proper techniques employed it's possible to ditch in water (Sullenburger, Hudson River). A steep descent into water at cruise or cruise-descent speed would be a guaranteed fatal outcome for everyone on board.

The theory that makes the most sense to me is the lane was hijacked, and landed somewhere in the jungle. Here is my "supporting evidence":

1. The stolen passports, of course.
2. The fact that the location beacons were not activated, means there was not crash impact to activate them.
3. The fact that no crash debris have been found yet says there was no crash.
4. The fact that some familly members have been able to call the cell phones but get no answers, means the cell phones are not deep under the ocean.

I hope we find the truth about this soon enough...

On a radio program today I heard from a probability specialist how the Air France plane wreck was finally located on the bottom of the Atlantic. The specialist discussed both the Malaysia Air and the Air France plane losses and the method by which they finally located the Air France plane. I understand That the theory was developed in WW2 by the British to find locations of U-Boats. Basically it uses all unsuccessful search attempts, ocean currents, and all available data to finally pin point a likely location of the crashed Air France plane. It is a long process. The specialist also pointed out that it took 6 days before the first pieces of the Air France wreck were located floating on the Atlantic. And it took two years to finally locate the plane wreck after the probability theory was applied. Then it was found within one week!

From Wikipedia:

http://en.wikipedia.org/wiki/Air_France_Flight_447

"2011 search and recovery[edit]In July 2010, the US-based search consultancy Metron had been engaged to draw up a probability map of where to focus the search, based on prior probabilities from flight data and local condition reports, combined with the results from the previous searches. The Metron team used what it described as "classic" Bayesian search methods, an approach that had previously been successful in the search for the submarine USS Scorpion. Phase 4 of the search operation started in the area identified by the Metron study as being the most likely resting place of flight 447.[119]


Cable ship Île de Sein was assigned to assist in the recovery of materials from the ocean floor.Within a week of resuming of the search operation, on 3 April 2011, a team led by the Woods Hole Oceanographic Institution operating full ocean depth autonomous underwater vehicles (AUVs) owned by the Waitt Institute discovered, by means of sidescan sonar, a large portion of debris field from flight AF447.[119] Further debris and bodies, still trapped in the partly intact remains of the aircraft's fuselage, were located in water depths of between 3,800 to 4,000 metres (2,100 to 2,200 fathoms; 12,500 to 13,100 ft). The debris was found to be lying in a relatively flat and silty area of the ocean floor (as opposed to the extremely mountainous topography that was originally believed to be AF447's final resting place).[citation needed] Other items found were engines, wing parts and the landing gear.[120]

"

Anybody hear from DB Cooper lately?

Keep it simple. Plane had a catastrophic event, comms systems cut off, from crusing speed and altitude it plunged into ocean, beacons all underwater thus not detectable. Not found debris yet - but its a big ocean.

But the Gulf of Thailand is not deep at all. Compared to where Air France ended up, it's like wading.

Black boxes are supposed to ping for up to a month, I understand. That signal could be picked up by sensitive Navy audio locator equipment. right?

This.

Once active, the Dukane DK120 emits a pulse once a second that can be detected by sonar equipment up to two nautical miles away. The beacon works at a depth of 20,000 feet — far deeper than the waters where officials believe the Malaysian plane went down.

Read more: Malaysia Airlines Black Boxes - Business Insider

But could it also fly "under the radar" and land somewhere else?

I discount the cellphone thing. That makes no sense. What are people expecting to get? A busy signal? Call any cell phone that's off.

A Viet. Air Controller thinks he' saw that on his console. Nobody knows for sure. No good pilot would turn around without getting on the radio. I also heard the plane has 5 electrical systems and 3-5 radios.

Then why was there an abrupt loss of contact on radar?

Everything that I've read indicates that the ATC in that part of the world has sparse radar coverage and relies instead on the aircraft transponder signal and location reporting from the crew. Unlike the USA, this is apparently pretty common in less developed nations. Were that the case, loss of contact could have been as easy as switching off the transponder.

Different world, but in the USA if you switched off the transponder and quit responding to radio calls you would have some F16 escorts pretty quickly.