odoberon
Maybe I'm confused, and my second interview was with Bloomberg. I had about seven interview windows open at one point.
Anyway, the link is there. Thats my source.

I'm confident he said it…and twice.
And I find it pretty significant.

This is exactly NOT what I was attempting to explain. Firstly, as a bit of context, one of the most powerful computers you will ever come close to is in your mobile phone. The digital signal processors in these cheap phones pack astonishing punch, and run "fast". They are pretty well dedicated hardware only good for running phone comms, so not as general purpose as an Intel i7 for example, but by some measures much more powerful. Don't underestimate the power in relatively cheap comms kit. Inmarsat C may not support high data rates, but remember it is serving many many planes and many many ships all at the same time.

The key point here is that I am NOT requiring a response in a nanosecond. The response could be half a second later - 500,000,000 nanoseconds later. The terminal just counts ticks while a far more pedestrian processor prepares the response and sets it up ready to be sent, and it is then sent at the right "tick". The satellite knows the defined protocol and so can eliminate the delay, giving it access to the actual "flight" time of the message.

But I also said these are communication systems, not navigation systems. The overall system is designed to maximise the data they can handle as it is data that makes money. They could at one extreme simply say we have no idea where each user station is, we will provide in the protocol a "window" wide enough to accommodate the user being anywhere over the 1/3 of the globe. That would mean the satellite had wasted potential fee earning capacity waiting for the full potential window for each and every communication exchange, when in fact it can reduce, though not eliminate the window.

My explanation was, as I had said, simplified. In practice there are a whole load of other complications, spreading data bits over many carrier cycles and error handling codes etc etc all of which will introduce more variability, but at the heart the system is operating at 1600 MHz, giving an inherent timing capability irrespective of GPS time stamps etc, with the potential of measuremment to quite high levels of accuracy. In practice the level will not approach this - but talk of "miliseconds" and hundreds of Km is not appropriate. The underlying principles may be designed in the 1980s - as was GPS - but we are not talking valves and clockwork here!

I say again, I can go to my hardware shop and buy for a few £/$/Eu a handheld laser tape measure that can fire and time a pulse of light sufficient to measure distance to a few mm. Give it a more stable clock - which the satellite will have, and using the same principle of counting ticks you can time to great accuracy over very long periods, eliminate the "processing" time at the receiver by specifying how many ticks later the reply is sent, and there you have a system with the potential of astonishing accuracy - just as GPS has.

But one last repeat - Inmarsat is a comms system designed to support comms. It is talked of as a bent pipe, but that is a great simplification. The content of the data being exchanged may appear to pass through a bent pipe, but there is a lot going on over and above passing the data to keep the pipe itself working.

Center of gravity theory.
 

if yours and all other theory's about flying further is correct without electrical or any control who will take care about trimming,we also have to know the c.g. of the aircraft, because the c.g. will shift and there will be no trimming so the aircraft will climb or descend during fuel burn.

"I am an ATC and the transcript also surprised me.
I guess the problem is that it is a translation from English to Chinese and then to English. However, the lack of read back is not explained by incorrect translation."


I lived in China (next door to the Air China Airbus rep - thereby hung a few tales...) for a few years. Believe you me, a translation into and then out of Chinese, a language very different to English, can very easily explain the lack of read back!

Medan airport ATC did they pick anything up? If it came back there way as suggested they should.
There is also a fair size Base close to there with a fair few fighter jets. Again not heard anything from them?

The north path would be very embarrassing for many people.
The south path hypothesis (fire - decompression - zombie a/c), however unlikely, is the only one that allows to save face for all countries (eastern and western) affected in some way by this 'event'. Any other explanation would point to incompetence or worse, misbehaviour by some governments.

So I guess we'll have to buy that one.

Castleford Tiger,
Still a lot of unanswered questions. They must have something that area of airspace very busy. The investigators and search coordinators in Malaysia who are running this SAR op may need to keep checking all reports and sightings they have be given. Of course we don't know what they have been given, only snippets and releases from the so called Us officials and Chinese news conferences etc have been leaked to the media.
Maybe something they were given days ago and discounted previously may be more relevant now, and needs further investigation. I just hope the foreign investigators who have volunteered their services from different bureaus are being utilized to their fullest. The search window is so large now. No stone should be left unturned.

I noticed the wording at the time of interview and wondered about the "steadily away from the satellite". At last military radar fix the plane was two ping hours north of the equator so would need one hour (maybe two) coming towards the satellite to cross the equator on the journey south. Was he referring to the last few pings or the continuous set?

Nigel OsborneFrom personal experience signal from a transponder may not necessarily be turned off deliberately. I am well aware that the vintage transponder in the C152 which I was flying was likely to be far less refined than that on MH370, however, in my particular case was asked by D&D to squawk 7700 and promptly complied - or so I thought. The transponder was certainly set correctly and should have been squawking but in fact was not. The request to squawk 7700 was the last transmission from D&D which I was able to hear for quite some time. D&D could hear me, but I couldn't hear D&D (or at least all transmissions from D&D were almost inaudible and muffled with no identifiable words). Communication was eventually restored via an Emirates Airbus and following a request to turn up the volume on the radio (it was already at maximum) I was asked to squawk 7700. My reply was that I was already doing that but would recycle, did so, and the problem was resolved. It is entirely possible that the crew of MH370 did squawk 7700 but was completely unaware that the transponder was not functioning.

@felix505


Several posters have stated that ATC is only available for sectors west and north of KL.

Edited to add: I meant listening in to ATC, not actual control. obviously!

Nigel Osborne

Perhaps you should have a think about the reasons why we need to be able to turn it off.

facts
 

Have I got this right?
The secondary response disappeared, then primary return disappeared. R/T shut down.....

Did somebody continuously track the a/c after that..who...verified?

So, the a/ may have disintegrated, it may have dropped below radar cover.
Maybe Blind Velocity Speed (unlikely at cruising speed and altitude) or Tangential Fading. (Radar Type in use ?)

So who continuously tracked the primary return?

If it was not continuously tracked it becomes unidentified. Who then re-identified it and how ? A primary return way off the flight planned track ??

I don`t think so.

McLaughlin might not have meant that all (eight?) distances (0111-0811) to the satellite were monotonically increasing - perhaps just the final few.

If he did mean that all eight distances were steadily increasing, then to accord with the timings, the number of possible routes likely isn't very large.

I just find it difficult to comprehend, that after 2 weeks, still no sure on where it is.
Surely if they can spot the plate numbers on cars from satellites, then surely they can figure out 370 and it's location, if intact.
Also, once it disappeared, I would like to really know, what and whom the Malaysian ATC, contact immediately.
I think, there is a lot that we are not been told, for some odd conspiracy.

One of the many puzzles I have lies in the (by now basic) assumption that the a/c for some reason 'tracked' along the 40degree Inmarsat arc. Do we not think that would be a remarkable co-incidence?

Good point. Pressure altitude is NOT the actual altitude.

BOAC, either "track" is an area of best probability X nm wide. Depending upon the angular precision, and the number of "degree circles" it may have crossed, the thickness of that band looks to me to get into a few hundred miles either side of the theoretical center. I don't like thinking of those arcs as a "track" but as "areas of probability" that have variation between estimated points/times.

I did a little back of the napkin math. One degree of error or imprecision is in the range of 600 nm.

I am on board with your raised eyebrow regarding such a coincidence.

I understand why the pilots need to be able to switch off the transponder in case of malfunction. However, would it be possible to have a secondary transponder on board which would be automatically activated in the event that the primary was switched off? Perhaps the backup could even be battery powered, and could be set to squawk a particular "warning" code. (A warning code indicating there -could- be a problem, rather than an emergency code indicating hijack, etc.) Is there a reason that wouldn't work? It would be unlikely that two different transponders with two different power supplies would both have electrical malfunctions at the same time, so there would be no reason to shut both off.

jug: some pages back, a 777 operator indicated 777's have two transponders. Switching from one to the other pretty easy.

This makes sense, having two transponders as a measure of redundancy. Large airliners travel in dense traffic control areas in the departure and arrival phases of flight. Having the transponder working so that ATC knows who you are, and where you are, is to me a critical requirement, both for safety and for timely arrivals and sequencing.

Source of Chinese Image
 

From the Daily Telegraph online


"11.53 Here's the latest information from SASTIND, China's State Administration of Science, Technology and Industry for National Defence, via state news agency Xinhua:
Captured by the high-definition earth observation satellite "Gaofen-1" at around 12 a.m. on March 18 Beijing Time, the imagery spotted the object at 44 degrees, 57 minutes south latitude, and 90 degrees, 13 minutes east longitude, in the southern Indian Ocean, the SASTIND said"