Malaysian Airlines MH370 contact lost

[500N]

Walnut

I think we are a long way from a Comet type scenario.

[portmanteau]

lonewolf 50. you are the KL radar controller watching 370 on the screen in front of you. you instruct it to contact HCM then watch it continue NE. the moment you see its label vanish ( when the aircraft transponder stops), you reach for the phone to ask HCM atcc fellow controller on a direct line, whether he has ok contact with 370. he says no and may even tell you then that he can see it has turned back. you and he there and then initiate standard search and rescue procedures. atcos do not have to refer to anyone else first, their responsibility is to get the procedure under way without delay because time is of the essence. adjoining atccs are informed at the same time.

[Andy_S]

Originally Posted by Walnut

However historically as only about 10% or less of air crashes are caused by high jack or suicide then it has to be assumed that an aircraft malfunction has occurred. As such the travelling public are going to be very unhappy climbing aboard a B777 with a mechanical flaw.

In the absence of anything new to report and the re-emergence of silly conspiracy theories, I’ve been avoiding any discussion of MH370. But I can’t let nonsense like this go unchallenged.

No, it does not have to be assumed that an ‘aircraft malfunction’ took place. There’s not one, tiny, shred of evidence to support such an absurd statement.

How long has the 777 been in service? How many 777’s are currently flying? And how many 777 hull losses have there been? You don’t have to be a mathematician to work out that the aircraft has an excellent safety record.

It’s been over three weeks now since the disappearance of MH370. I have seen no evidence, anecdotal or otherwise, that in that time the ‘travelling public’ have been ‘very unhappy’ about ‘climbing aboard’ a 777. If you have such evidence, perhaps you could present it to back up your assertion.

[DaveReidUK]

However historically as only about 10% or less of air crashes are caused by high jack or suicide then it has to be assumed that an aircraft malfunction has occurred.

Why is there a requirement that any assumptions should be made ?

[MPN11]

Originally Posted by portmanteau

lonewolf 50. you are the KL radar controller watching 370 on the screen in front of you. you instruct it to contact HCM then watch it continue NE. the moment you see its label vanish ( when the aircraft transponder stops), you reach for the phone to ask HCM atcc fellow controller on a direct line, whether he has ok contact with 370. he says no and may even tell you then that he can see it has turned back. you and he there and then initiate standard search and rescue procedures.

Having instructed many, many, thousands of aircraft to contact the next control agency in my career, I can assure you that from an ATCO's perspective that's it. He's gone, flight strip in bin, screen wiped, Endex.

If we went around calling colleagues saying "Have you got him yet?" There would be no time left to control the remaining aircraft on frequency.

It doesn't happen.

[pax2908]

Sorry, simple question, maybe already answered (blacksheep ?)

Does the Doppler analysis / projected track, depend, OR does not depend, on the accuracy
of the local clock (the clock of the SATCOM terminal on the aircraft) ?

[BusyB]

I may have missed it but I have seen no consideration given to the "Divert to ----" key on the FMC. If that was selected surely the a/c would turn to fly there and continue on if no further selections made

[WillFlyForCheese]

Re: Inmarsat data

Having read Duncan Steel's writings on Inmarsat data not ruling out a northerly route, and the apparent high confidence in government officials that the Inmarsat data confirm a southerly route . . .

I would like to see some type of confirmation that the folks that undertook the analysis of the data can reproduce accurate findings with aircraft that were not lost.

In other words - provide them the raw data from completed flights. Only the data that would be similar to that data sent by MH370. Have them calculate the position of that aircraft along the flight route and compare it to what actually happened. Possible? Was it done?

Basic scientific method - right?

[flash8]

Prof. Duncan Steel's CV is extremely impressive, to the extent that he is likely one of the few people on earth with the credentials to be taken seriously in disputing the data, having arguably comparable if not greater experience than the Inmarsat team members.

With no flotsam found to date I for one remain somewhat skeptical the a/c ended up in the Indian Ocean.

Additionally I just don't feel confident that we have been told the entire story.

[mm_flynn]

Originally Posted by pax2908

Sorry, simple question, maybe already answered (blacksheep ?)

Does the Doppler analysis / projected track, depend, OR does not depend, on the accuracy
of the local clock (the clock of the SATCOM terminal on the aircraft) ?

My understanding of the two measurements is
1 Doppler - which is a measure of the frequency shift of the Aircraft signal when received at this earth station and is dependent on the accuracy of the 'transmitting frequency' probably more accurately the precise bit rate. For the system to work, this needs to be very very accurate but is not a 'clock' in the sense of having a specific time, just a very accurate period between each bit. This measure tells if the plane was generally North or South of the satellite. I believe based on Inmarsat knowing the satellite's movement. But doesn't tell us much about the aircraft's speed or direction of flight.

2 The Ping - which is a time delay and tells us on which arc on the Earth the aircraft is located. The general conversation implies that it is a round trip delay of a message packet, however, it appears there is also is a calculation the satellite does to tell the Aircraft station what delay it needs to use from the satellite's reference clock in order to fit into the assigned TDM slot. This would be a pretty accurate number I order for the system to work effectively (because the more accurate each station is in hitting its time slot, the less buffer is needed between slots and the more data that can be transmitted). So if the arc is determined using this piece of data, it should be pretty accurate and pretty much independent of the condition of the Aircraft station.

I am sure a real expert will correct any errors. But from my perspective it seems very unlikely that Inmarsat will have gotten the Doppler direction wrong or the arc wrong. However, where the aircraft actually was on the arc depends on the assumptions of how fast it was going, and how steady that velocity was.

[Biggles1957]

Re: Inmarsat data

@WillFlyForCheese

I would like to see some type of confirmation that the folks that undertook the analysis of the data can reproduce accurate findings with aircraft that were not lost.

Inmarsat have said that they have indeed validated their findings by running the same analysis against their data from other scheduled MAH B777 flights where the flight path is known.

[Chronus]

Blacksheep`s commentary makes a lot of sense in setting out the limitations of satcom data analaysis carried out by INMARSAT.
INMARSAT announced that after six complete handshakes recorded at the ground station following ACARS, the a/c`s operational comms sytem stopped sending messages. INMARSAT was then able to calculate range of a/c from sat and time taken for signal to be sent and received. They then generated the well published Northern and Southern Corridors. Which seemed to cover a large chunk of mother earth and water. So got their heads back down and developed a second innovative technique which took into account the Doppler effect, which we all know from watching ambulances, police cars and for train spotters, locos. They analysed the frequency that the ground station expected to recieve and the one actually measured, which they told all is called the Burst Frequency Offset. They then checked this prediction with six other B777 a/c flying on the same day in various directions which resulted in a good match with the Southern Corridor. So off went all the troops in that direction.
So it would seem to me at least, that the whole thing is built on much theory and little hard fact. Until such time when some debris is washed on someone`s shores nothing will be known.

[jmmilner]

Nuclear Sub Added to Search

Now that HMS Tireless, the oldest active member of the Trafalgar class, has been added to the search, do we need to reconsider the usefulness of such an asset in light of lessons learned with AF447? In the AF case, the open literature suggests the on-board acoustic sensors were unable to locate the black boxes but we now know that the pinger on the CVR was defective when finally recovered. Perhaps some of the bright boys have added functionality, within the limits imposed by the physics of the actual sensors, to detect relevant frequencies. Sadly, Tireless, once scheduled to be retired last year, is also the only Trafalgar class not to retrofitted with the Sonar 2076 system, which the RN claims is the most advanced in the world. Seems like an odd choice on the surface (pun?) but perhaps in this case older is better while avoiding revealing just how good the new kit is.

[YYZjim]

Preliminary incident report within 30 days

Under the terms of the IATA/ICAO treaties, the authorities in charge of investigating an aircraft incident involving death are required to publish a preliminary report within thirty (30) days of the incident. Recent experience with the Malaysian government suggests we should set the bar for details and truthfulness pretty low. Perhaps April 7th will come and go with no report at all. After all, there is no evidence of casualties. Nor, to be precise about it, is anything definitive known about the incident/accident. It would be nice to know the assumptions, science and conclusions which underpin the search and investigation so far, but they would not necessarily be described in an accident report. It is disheartening to imagine that we may never know what happened to MH370. Even worse: we may never find out why the search took the turns it did.

[Biggles1957]

Re: Inmarsat data

@WillFlyForCheese

I agree; as the UK AAIB have reviewed Inmarsat's work, presumably they have reviewed these tests as well. That the source data has not been made public has caused much debate here on PPRuNe.

I don't understand what Inmarsat are showing on their "Burst Frequency Offset Analysis" chart for the time-period, from take-off up to the time we are led to believe last primary radar contact was lost at approx 18:20UTC i.e. what the "Predicted Track" represents for this time period - the measured track here appears wayward but after this point it follows their Predicted Southern Track.

It is disappointing the Malaysians have not made public a definitive track from the last known position in the South China Sea at 17:20UTC, when the transponder stopped, to the position of last primary radar contact in the Strait of Malacca at 18:20UTC. (The Chinese media have released an alleged, incomplete, trace for the Strait of Malacca, but the Malaysians refused to comment on this.) I suspect that events including route/speed/altitude etc in that missing hour are key to this mystery.

[Datayq1]

Chinese radar track

@biggles:

The Chinese media have released an alleged, incomplete, trace for the Strait of Malacca,

The only radar track that I've seen from the Chinese (families) is in the South China Sea/Gulf of Thailand.

Is there another (Chinese version) for the Malaccan Straits?

[dicksorchard]

Anwar Ibrahim talks of Malaysian Government cover up ?

Do not know how reliable this report is but it makes interesting reading - Anyone got anything to add to the details on radar Capture .

MH370 Malaysia Airlines: Anwar Ibrahim says government purposefully concealing information - Telegraph

[Lonewolf_50]

@dicksorchard. Nothing like some political noise to keep people stirred up. Does BFA to help find the missing aircraft, however ... comments on the criticisms from the political opposition.

He indicated that it was even possible that there was complicity by authorities on the ground in what happened to the plane and the 239 people on board.

Gee, political opposition indulges in speculation about the evil in current party in power. Straight out of Politics 101 playbook. Not original.

It was “not only unacceptable but not possible, not feasible” that the plane had not been sighted by the Marconi radar system immediately after it changed course.

I'll suggest the man has never served a day in uniform, nor ever sat at a radar console on the mid watch.

The radar, he said, would have instantly detected the Boeing 777 as it travelled east to west across “at least four” Malaysian provinces.

Indeed, if it was on, operating as advertised, and manned.

Mr Anwar said it was “baffling” that the country’s air force had “remained silent”, and claimed that it “should take three minutes under SOP (standard operating procedure) for the air force planes to go. And there was no response.”

Maybe nobody told the Air Force Planes to go. Maybe they were not in the Alert 5 status at midnight-ish on a Friday night.

He added: “We don’t have the sophistication of the United States or Britain but still we have the capacity to protect our borders.”

Fair statement.

It was “clearly baffling”, he said, to suggest that radar operators had been unable to observe the plane’s progress.

Maybe they saw it and it didn't register that something was well out of order. See above: midnight to dawn shift, your A side is probably not on watch.

@mickjoebill: why would they leave the navlights on if it's a human up to no good? If it was a "something's wrong" scenario, interesting idea there.

[WillowRun 6-3]

Regarding the 30-day prelim report requirement

Poster "YYZjim" recently noted the standard requirement of a preliminary report at the 30-day mark. Also noted was that one could argue as to whether the triggering event is known to have occurred - there's obviously no physical investigation site yet, etc.

In my legal view, there is unequivocally and literally zero basis to regard the incident as in abeyance. True, no wreckage (or other confirmatory physical evidence). But certainly the 30-day clock began to wind at the point in time no later than scheduled arrival plus 24 hours. I'd not want to advocate for any entity with any degree of involvement in the Mystery of MH370 that the fact of said Mystery bars the 30-day clock from starting to wind.

But that timing point is merely procedural. The substantive stuff is hinted at by YYZjim's noticing that Malaysian authorities seem not prepared to add generation of such a report to their already-overwhelmed capacities. One realizes the ICAO legal system does not presently contemplate, and perhaps does not even allow, a kind of mobilization of investigatory, legal, and technical expertise on a multi-national level. But this incident dramatically breaks the mold - and it's a fair bet that when the facts ultimately do become known, that breakage will extend far more deeply. So it is time to innovate, on the legal and administrative agency front. (I won't repeat earlier posts advocating broad outlines of such new approach.)

[olasek]

But certainly the 30-day clock began to wind at the point in time no later than scheduled arrival plus 24 hours.

I think this a bit humorous, who cares about 30 days, 60 days, etc.
Cameroon didn't bother to release any preliminary report when KQ507 crashed and the final report was released like 3 years after the crash.