I don't think you can rule out a professional hijack yet

For those of you looking for more satellite protocol information. This appears to contain quite a lot of the frequency, channel, packet info etc
Report of the seventh meeting

I doubt it's really going to get us any closer than the perfectly understandable inmarsat ping arc map, plus the measured and apparently tested against 777 airframes with same electronics suite doppler shifts...

Let's get it right -

Radios etc were not 'switched off', they stopped working.

Earlier posts referred to the effects of 'neurotoxic particulates' on flight crew performance.

We still haven't seen a radar plot.

Or the cargo manifest, I think?

And finally, how did they 'positively identify' an 'unidentified primary target' without taking a look at it?

Looks like any investigation might be held here in Aus ?

Australia to represent Malaysia in MH370 investigation

Australia has agreed to be an “accredited representative” of Malaysia in the investigation into missing Malaysian Airlines Flight MH370, a development that could lead to the lengthy probe into the jet's disappearance being based here. The announcement was made by Malaysia’s Prime Minister Najib Razak on his visit to Perth on Thursday and came as the search zone was “further refined” and shifted north as aircraft, ships and a nuclear submarine continued the hunt for remnants of the passenger plane.
As revealed by Fairfax Media, a group of nations have been pressing Malaysia to allow the investigation into MH370 to be based in Australia amid concerns about the chaotic handling in Kuala Lumpur of its disappearance.
While Malaysia will formally head the investigation as required by international convention, Mr Najib told media on Thursday that Australia was now “an accredited representative”.

Or, perhaps better, nothing was received from the aircraft except SATCOM communication?

I agree with Martynemh All his questions must be answered. The industry can not less this incident go unresolved, with circa 1100 777s still flying. Remember the Comet disappearance. The radar plot must be published in full, along with the cargo manifest.
Whatever the political pressure the Malaysian PM should take the lead here.

That's not how I read it.

Australia is not representing Malaysia, poor choice of words on the journalist's part. Australia is an accredited representative to the investigation, which is only to be expected per ICAO Annex 13, 5.23:

"Any State that provides an operational base for field investigations, or is involved in search and rescue or wreckage recovery operations ... may also be invited to appoint an accredited representative to participate in the investigation".

Walnut

Sadly as in life we cannot always get what we want. Personally I think we are as likely to get a definitive answer to this tragic event as you are likely to be the next man to set foot on the moon.
In a week the blackboxes will run out of charge and then what? How much has it cost already for all the searches to date?
The chances of even getting an answer as to where the wreckage lies is probably almost zero.
so barring a miracle this will end up as one of lifes unsolved mysteries

Pace

Age Related Drift and "On Conditrion" Maintenance
 

I admit that Inmarsat and academic scientists know their systems inside out, but my question on the accuracy of their prediction is based on my own knowledge of aircraft systems and equipment that interface with the outside world [40+ years as an avionics specialist on Boeing 707, 737, 747, 757, 767 and currently on 787].

The MOPS for a Mode S Transponder (which includes Modes A and C functions) requires a very precise 8 microsecond interval to identify an interrogation, and trigger the response. The response is then either a 56 microsecond or a 112 microsecond burst of data. The 120 microsecond reply is very finely calibrated. A recent Airworthiness Directive (2014-05-07 for those who are interested) directed at a particular manufacturer's Mode S transponder requires them to be sent for bench testing and re-alignment every 4 years to detect and correct age related alignment drift in the electronic components. Such drift cannot be noted by crew or maintenance monitoring. DME Interrogators require similar calibration accuracy, but DME indications are directly monitored by the aircew and drift is quickly noted.

Now, compared to the precision calibration of ATC transponders and DME interrogators, there are no such requirements for Satcom systems. A one microsecond variation within the airborne equipment's processing circuits could easily result in a 2,000 km error in the position calculation. There is nothing in the equipment specifications that makes that unlikely - the equipment is just as likely to suffer age related drift as any other avionics equipment. Unlike transponders, Satcom equipment is maintained purely "On Condition" and there is absolutely no way that the scientists producing their range predictions, based on analysis of "handshake" responses that were never intended for range determination, could know the internal condition of the airborne components of the Satcom system. I have been sceptical of the predicted range arcs since they were first promulgated and nothing I have seen or heard since has changed my opinion - these Satcom range arcs are of questionable accuracy.

Sadly, they are the only thing the search coordinators have to go on.

AMSS protocols
 

Well spotted JoBloggs2.

That material made it into ICAO Annex 10, Volume III in more-or-less that form. Now I think it has been moved into an ICAO manual which forms and appendix or some-such to Annex 10. It is based on the Inmarsat specification as outlined in their System Definition Manual for their aeronautical service. It should be mandatory bedtime reading for those commenting on satcom matters on this site.

Interestingly, the so-called "pings" will probably contain information pertinent to the investigation, such as class of log-on (high gain, low gain etc.) which will indicate whether the aircraft antenna was pointing at the satellite and which in turn will indicate the status of the FMS.

All good stuff.

They don't really need to know the exact condition: they could use the "pings" on ground, when the satcom gear is in a known location, to calibrate from. Barring extreme drift during flight, this should be very accurate.

Blacksheep
 

Light (and radio waves) moves quickly. I cannot keep up with it.

But. The speed of light is approx 3 x 10^8 metres per second. One microsecond is 1 x 10^-6 seconds.
So, in one microsecond light (and radio) will travel approx 3 x 10^2 metres.
At an "altitude" of 40 degrees - lets change that to 45 degrees to keep it simpe - a 300 metre variation in the hypotenuse would mean, roughly, a 200 metre variation in the horizontal position.

Is my maths wrong? If not, hardly 2,000Km.

And as has already been posted, while the equipment may not be bench calibrated , Inmarsat are very likely to have had similar "ping" data from when the plane's postion was known with considerable precision - as when on the ground - to calibrate their analysis.

There will, of course, be variances between different pieces of equipment. An individual piece of equipment will also have variations over time. But do not underestimate the sophistication of the equipment, particularly of the complete end to end comms system including the plane mounted equipment, the orbiter and the ground station. Or the capabilities, experience, and intelligence of the people that have carried out the analysis.

Has there been any discussion regarding the background checks of the flight attendants? Certainly they would be somewhat familiar with the cockpit layout from sitting in there while the pilots go on bathroom breaks. If one of them had ill intentions and a modicum of flight-simulator experience they could easily have murdered the remaining pilot (using the axe or any other heavy object) while the other was outside, and initiate a sequence of events leading to this aircraft's disappearance. An FA with a long-stewing intention of accomplishing something like this could gain all the information they would need to shut off various systems (communication, dump cabin pressure, etc) simply by asking questions while seated in the cockpit over various flights. Not to mention studying any number of websites and messing around with X-Plane or whatever.

Let's face it it's not rocket science here. Pull a couple of circuit breakers, put on an O2 mask, manipulate some cabin pressure controls to dump the cabin, turn the altitude knob and pull, type a few keystrokes into the FMS, and that's it. A little homework is all it would take.

If according to the latest (CNN so take it with a grain of salt) all passengers and the pilots have been cleared of suspicion yet they are STILL viewing the aircraft's maneuvers as a "criminal act", then that basically just leaves the cabin crew, correct?

That might make sense until :
Then, that could fit with information publicly available :
Flies around Indonesian airspace
Turns the heading knob to 180 and drops O2 mask ...

DH call:
No, they are not obliged to. The countries who have contributed to the search will foot their own bills initially I would think. So China will be paying for any of its aircraft that it is using. Whether any bills would end up being charged to the airliner's insurers, I don't know. Australia will pay for all of its S&R efforts, eg those inside its S&R zone.

Don't suppose you have any kind of PROOF or INDICATION to support this?

BTW I am keeping a very open mind on this sad event, but really..........:suspect:

To simplify it even further. Light travels roughly one foot per nanosecond.

One microsecond is 1000 nanoseconds.

One microsecond is ~ 1000 feet not 6,561,679 feet 9 31⁄64 inches (2000 km)

I haven't seen any or much criticism of Australia's efforts, or for that matter Vietnam, India who although the last two got tardy with Malaysia, who could blame them.

Apart from the number of Chinese being involved, the other MAJOR reason for China's huge response is because they got whipped badly a few years back for the tardy Chinese response to helping out a neighbour when every other country in the world put all hands to the grind stone !

They (the Chinese) didn't like it and were determined to make sure that type of criticism didn't happen again.

Re costs, remember the military costs are incurred whether they are searching for the aircraft or doing normal flying duties or sitting on the flight line.

It would take sometime for the news to be shared with other civil units, sharing with the military would take longer if at all. Remember, the immediate thoughts were that the aircraft had dissappeared somewhere en-route to Vietnam at the extreme edge of Malaysian radar cover. Why contact internal military units to look for an aircraft that was assumed to be either en-route more than 200 miles away with some complex comms failure? After half an hour or so it was assumed that the aircraft was in the South China Sea again, why contact military? It was only when the news got out after seveal hours that the military said we think that one flew back overland out into the Malacca Straights. This was reported but then Iwould think the question was "are you absolutely sure?" - so while it was being checked the 'civilian loss of radar' contact was given as the time of last radar. Only when the military had time to pull the tapes and recheck did the time go back to 2:40 loss of primary radar over the Malacca Straights.

I see nothing suspicious in this although the management of information to the baying media could have been better handled.

@9151 martynemh

Let's get it right -

Radios etc were not 'switched off', they stopped working.

Can I ask for clarification? If you are saying that no-one knows if the radios were switched off then I agree. However, your post could be read that the radios were not switched off because they broke down...then I disagree as how can anyone on the ground know that?