Malaysian Airlines MH370 contact lost

[Kooljack]

AAIB and Inmarsat has confirm through further data analysis, that MH370 had followed the Southern corridor path and ended up in the South Indian Ocean.

[oldoberon]

At this point everyone really has to accept the immense efforts and accuracy of the results by Inmarsat, they are owed a huge vote of thanks by all.

Be interesting to see how they were finally able to distinguish north from south.

Prof on BBC just said they & AAIB have basically crammed 12 months R&D into 2 weeks

[Killaroo]

Yes, this means the tracking information is confirmed officially (new and positive analysis by Inmarsat).
They haven't given up looking. They seem to know now where to look with more certainty.

So is there any remaining doubt that this was an intentional act?

[nupogodi]

And the award for most useless press conference goes to.........


I mean, really? Was that worth the razzmatazz with the prime minister flying in?

The way he sounded, it was almost like a closure to the investigation. Shouldn't this confirmation be the start? He didn't even answer questions.....

You would not expect the prime minister to answer questions on a highly technical investigation. The technical questions will be answered at tomorrow's presser by people close to the investigation, I imagine.

[skytrax]

@opendoor

Sliderafts dont have elts. The plane has 2, one in the fron at L1 and one at the aft. They are to be removed by the crew in emergency. They do start transmitting when hit t he water but for only 50hrs.

[slats11]

I am curious about the technical details of this further INMARSAT ping analysis.


As are we all. I doubt the true explanation has anything to do with Inmarsat.

Most likely (to me) is that another satellite also received the pings, and this allowed them to eliminate the north and to dramatically narrow the southern search area.

The posturing has been very positive for quite a few days. A fairly significant announcement from Aust PM to Malaysian PM based on a couple of grainy images? I don't think so.

They diverted that Norwegian car carrier several days before they announced the first satellite images of debris. And then a large multinational effort with aircraft from 5-6 countries focussed on this (relatively) small area.

They also confirmed that the initial debris had been subject to corroboration by other satellites.

[slayerdude]

Important step by pm. It's a declaration that rescue phase is over and now recovery phase is in effect. In economic terms, during the recovery phase the Malaysian government/ MAS picks up the tab in cost.... All the fuel for those planes and ships plus operating cost. So malasian tax payers paying for this I guess

[atr-drivr]

Anyone know if the Norwegian car carrier is still on station? Or is it out of the new search area?

[Taildragger67]

So what is this really based on? Seems circumstantial at best. There has to be more concrete evidence than this. If I was a family member, I'd be unimpressed.

It's new news. They'd been pilloried for possibly keeping info to themselves, now they're copping it for relaying new information.

By definition, unless / until the airframe / parts thereof / recorders (ie. "concrete evidence") are found, any conclusion will be circumstantial. :ugh:

Is it too much to expect that British satellite company Inmarsat and/or the UK's Air Accident Investigation Branch (AAIB) now make themselves available for a news conference to explain exactly what data they have, how they analyzed it and what conclusions they reached?

So far we only have third-hand reports of what Inmarsat has or doesn't have.

AAIB and Inmarsat are not running the investigation. News should be released by those who are. What you're saying is, for example, that any metallurgist who concludes something after looking at a bit of twisted metal, should jump on Twitbook and start babbling about it, possibly confusing everyone in the process. Quite frankly AMSA and Tony Abbott should arguably keep quiet (although their comments have been guarded).

[McRotor96]

And the award for most useless press conference goes to.........


I mean, really? Was that worth the razzmatazz with the prime minister flying in?

The way he sounded, it was almost like a closure to the investigation. Shouldn't this confirmation be the start? He didn't even answer questions.....

FFS. Can you even hear yourself? The man just told 239 families that their loved ones are dead. All hope is gone. The PM delivered this dreadful message with sensitivity and emotion. Of course there were no questions.

This is not some kind of online puzzle. This is real. And for the husbands, wives, children, mothers and fathers of those lost - their life has just been ruined.

[slats11]

Anyone know if the Norwegian car carrier is still on station? Or is it out of the new search area?

Guessing out of the area by now given other (and more capable) assets on scene. But someone a few days back posted very persuasive data that it sped up and changed course 3 (I think) days before they announced the search off Perth.

Anyway lets hope some debris is found soon. Concrete evidence will be more persuasive for to distressed relatives than will mathematical discussions about satellites.

[bono]

Hoegh St Petersburg was relieved yesterday from search duties at the request of the ship according to the briefing by AMSA.

[Cows getting bigger]

GreenOnGo, perhaps it is based upon 200+ families wanting/needing some closure. :mad:

What does it matter to the rest of us?

[Hempy]

The release of information to the public has NOT been in real time. Australian Naval assets were on their way to the search area 26 hours before it was announced, satellite information has been screened and kept secure.

[vfenext]

200kg of Lithium Batteries on board!MH370 transporting 200kg of lithium batteries: chief - 3/24/2014 - Flight Global (http://www.flightglobal.com/news/articles/mh370-transporting-200kg-of-lithium-batteries-chief-397333/)

[slats11]

The release of information to the public has NOT been in real time. Australian Naval assets were on their way to the search area 26 hours before it was announced, satellite information has been screened and kept secure.

All of which is quite appropriate and quite understandable.

I suspect the original Inmarsat 40 degree arc is true. But everyone was very dogmatic that was all the information available. As far as the satellite was concerned, the plane could have been anywhere on that arc at the time of the final ping.

If the Inmarsat data had been refined by other means, and if the US needed a cover explanation, who else would they turn to other than the UK?

[IanWorthington]

Interim report?
Is it too much to expect that British satellite company Inmarsat and/or the UK's Air Accident Investigation Branch (AAIB) now make themselves available for a news conference to explain exactly what data they have, how they analyzed it and what conclusions they reached?

So far we only have third-hand reports of what Inmarsat has or doesn't have.

Not really. The Beeb, at the least, have carried interviews with Inmarsat. Not that they added anything.

[Evey_Hammond]

Heartbreaking! :{

"Sydney Morning Herald's Philip Wen tweets: Relatives have learnt the news and are wailing openly at the Lido Hotel, some unable to walk. Medical staff still bringing in stretchers"

[Bobman84]

Nothing has been found, even as recent as 3 hours ago by local Australian statements.

Very suspicious to make assumptions based on no hard evidence (data is not necessarily credible here).

[bono]

"As a precautionary measure in case a debris field is located, U.S. Pacific Command has ordered U.S. Pacific Fleet to move a black box locator into the region, March 24.
If a debris field is confirmed, The Navy's Towed Pinger Locator 25 will add a significant advantage in locating the missing Malaysian aircraft's black box."


Read more: Navy Prepares Black Box Locator for MH370 Search (http://www.asdnews.com/news-54115/Navy_Prepares_Black_Box_Locator_for_MH370_Search.htm#ixzz2wt L1ZS3S)

[awblain]

That's all very well and good, but it doesn't do anything for finding the wreckage and the recorders. Unless someone has some radar data or intercepted Inmarsat broadcasts, then the mystery is probably going to
remain unsolved.

Perhaps it's time to try stacking weather satellite data for a contrail along the route after sunrise, and IR early warning data to try to pick out the engines?

[wiggy]

McRotor

This is not some kind of online puzzle

A plus one from me, well said.

There will be no prize for the best analysis or closest guess. Inmarsat, the AAIB, NTSB have got enough on their plate right now without pandering to the " I demand to know" brigade..guess what - right now we don't need to know. I, and I suspect others here will be strapping a strapping a T7 to my backside tomorrow, I want the investgators focused on the job, not on PR.

The PM did the decent and IMHO the right thing.

Maybe time for a little quiet reflection by some in this place as to what has gone on here and the suffering some people are going through?

[500N]

Interesting that the US dispatched a ship with towed array to the search area in the last few days.

Re information NOT being released in real time, not surprising and if you think of the criticisms the Malaysians endured by releasing info and then retracting it, I would say that the US, UK, Aust etc are being very careful. The only people who need to know are the families and the searchers, everyone else - especially the media - can wait.

At least Aust has lots of activity to keep the media busy and occupied.

[AirJing]

Indeed, very bad, although expected news.

But I am really flabbergasted that Malaysian Airlines chose to tell the relatives by text message. I mean seriously, what were they thinking? I've heard of people dumping their boyfriend or girlfriend by text message, but telling someone their loved one died in a remote part of the ocean in a plane crash by text message?

I think I'm going to ban Malaysian Airlines for my personal travel - not because of the crash, that could happen to any airline but they have not had that good a level of contact with the families for the last two weeks and then this text message is really unbelievable.

Banned.

"The following SMS message has been sent to relatives: "Malaysia Airlines deeply regrets that we have to assume beyond any reasonable doubt that MH370 has been lost and that none of those on board survived. As you will hear in the next hour from Malaysia's prime minister, we must now accept all evidence suggests the plane went down in the southern Indian Ocean.""

[max nightstop]

Inmarsat saying they have used Doppler effect to isolate the southern corridor and tested the theory on known flights. Hence their latest conclusion. Can only give a general location.

[Above The Clouds]

Wiggy
Maybe time for a little quiet reflection by some in this place as to what has gone on here and the suffering some people are going through?


Well said.

[paultr]

a bbc reporter has just been told by Inmarsat that their investigations were completed yesterday and involved the movements of other aircraft (some kind of more accurate calibration ?)

[Hornbill88]

There will be no prize for the best analysis or closest guess. Inmarsat, the AAIB, NTSB have got enough on thier plate right now without pandering to the " I demand to know" brigade..guess what - we don't need to know.

Wiggy I think we do need to know. We need to be confident that we can fly on 777s, that we can fly on Malaysia Airlines flights, that we can fly out of Malaysian airports. I agree with you that breathless speculation from fruitcakes on this site or from the press won' t get those questions answered, but the Malaysian government does need to get something out from its apparently interminable police investigation to start giving some assurance to all of us who fly in and out of Malaysia or on 777s.

[VinRouge]

http://www.pprune.org/8380536-post4502.html

Posted that Doppler could solve the rough track of the aircraft back on the 16th. Looks as if thats how they managed to go firm on the southern route.

Unless they have a truly tremendous receiver on the satellite, Doppler is only by a Hz or so, and would still not split North and South. The only way for Inmarsat to decide between tracks is on the possible routes highlighted by the series of eight pings. Indicated doppler effect pops up on our FMS, typically depending on sat geometry, you are looking at between 10 and 50 Hz difference, so not insignificant I believe. With multiple sats and a few complex equations, you can get a rough derived relative track and velocity which it loos as if Inmarsat have done in this case.

Whether any other agencies have been involved in locating potential wreckage is irrelevant. All that matters is the families can get closure and a rough search area is established to determine what why and possibly who was responsible.

[500N]

ORAC

"a super-secret installation just outside Alice Springs -- remains cloaked in secrecy."

Pine Gap is NOT super secret anymore. A fair bit of what goes on was disclosed in a book written by a person who works inside and all of it was fully approved before release with more detail than people thought. The media however like to blow it up as "super secret".

As to whether JOHR was working, we don't need to be told, as long as the relevant information is passed on which it would have been.

[slats11]

the " I demand to know" brigade..guess what - right now we don't need to know.

True.

I don't believe anyone here is demanding to know the details of "other means." We all surely accept that we won't be told - perhaps ever.

What I (and I think most people share) is a hope and conviction there is more information that will lead to the wreckage, lead to answers, and lead to closure for the relatives. Because the official information that has been released does not create very much hope of this.

I really don't give a damn exactly what this data is. I just hope it is there.

I believe this is the focus of most people here.

[AviatorDave]

While the media report that Najib Razak has now officially declared the plane as crashed with no survivors, based on satellite data analysis, I still feel uneasy about the whole case.

As far as I understand, actual debris from MH370 has not yet been found and positively identified. In that light, I consider Razak's statement as the most probable outcome, but in no way confirmed.

To me, it appears that due to public pressure and because of the upcoming car racing event, the Malaysian government wants to put a quick end to the story.

A lot of loose ends still need to be tied up.

[JamesGV]

MAS statement

"On behalf of all of us at Malaysia Airlines and all Malaysians, our prayers go out to all the loved ones of the 226 passengers and of our 13 friends and colleagues at this enormously painful time".

226 ? or 227 ? souls onboard

[cockpitvisit]

I can't believe some are still believing in their conspiracy theories and not accept that it could just be the result of a catastrophic decompression

In the past 15 years, the majority of fatal crashes during cruise flight were due to terrorism and pilot suicide.

I think there were only 2 passenger airliner crashes caused by mechanical reasons in the past 15 years (China Airlines disintegrating in flight, and Helios Airways loss of cabin pressure). Compare this to 3 pilot suicides during the same time period alone.

[JamesGV]

Pax manifest

http://www.malaysiaairlines.com/content/dam/mas/master/en/pdf/Malaysia%20Airlines%20Flight%20MH%20370%20Passenger%20Manife st_Nationality.pdf

227

[slats11]

Pax manifest

http://www.malaysiaairlines.com/cont...ationality.pdf

227

Thats very interesting. Why then did he say 226?

[wiggy]

Wiggy I think we do need to know.

I accept that from a customer and crew confidence point of view we need to know what happened to cause the accident as quickly as possible. My issue is with those who seem to need to know the source of every piece of information...if the AAIB want to claim that they worked out the possible position all by themselves without the help of the NSA or even GCHQ, I personally have no problem with that, and if the authorities want to keep any presumed liason secret so be it - that's the sort of thing we don't need to know, all IMHO of course.

[JakartaDean]

I have been thinking of this. There were hourly pings which can be used to calculate the arcs. Distance between the arcs gives the average hourly speed towards the satellite. Doppler data would give the momentary speed towards the satellite at the moment of the ping. Doppler data would not give too much additional information, but would curtail the set of possible tracks.

I have always been sceptical that the logs would contain detailed enough data to estimate speed. Why would a desperate-for-storage-space engineer add logs for such extraneous information? (If she did, hats off as it may have made a difference to this investigation.)

Another possibility could be, that inmarsat had ping data from previous flights in their logs. If this data contains signal strength it could be feasible to calculate the radiation pattern of the a/c antenna. If there was a significant asymmetry in the a/c antenna it could be deduced whether the starboard or port side of the antenna pointed to the satellite.

Again, I doubt they would give scarce log space for signal strength data, unless it serves other purposes. I wonder if they haven't been using the slight variations above / below the equator that the satellite travels, with an assumption of constant speed and bearing, to eliminate the northern arc.

[413X3]

As if all the various governments and their militaries don't already know what capabilities there are out there? During this time of tragedy and confusion, classifying everything as a state secret, not sharing data with other agencies/governments or the media, and worst of all the families who are being dragged through emotional roller coaster after emotional roller coaster is all quite ridiculous. We are not living in the cold war where everyone is a spy and every country is trying to destroy you. This emotional scaring of the people who lived through those times is still quite apparent unfortunately. But the past decades it has been to the detriment of the rest of society than some people refuse to drop the us vs them belief.

[Nik4Me]

Originally was 227 pax and 12 crew, later they mention flight engineer as being there- standby travel? So it comes as 13 from MAS, 226 remaining as Pax

[sky9]

"Inmarsat saying they have used Doppler effect to isolate the southern corridor and tested the theory on known flights. Hence their latest conclusion. Can only give a general location."

Some of us on PPRuNe were discussing the probability of that a couple of days ago.

[OleOle]

JakartaDean,

I have always been sceptical that the logs would contain detailed enough data to estimate speed. Why would a desperate-for-storage-space engineer add logs for such extraneous information? (If she did, hats off as it may have made a difference to this investigation.)

That was my first thought too. But on second thought the single downlink sat -> ground station probably needs as much resources as one link between a/c and sat. To communicate with the a/c the sat has to "illuminate" the whole hemisphere to be receivable by a tiny a/c antenna. In contrast to that the downlink to the ground station can be one concentrated beam and the antenna on the ground can be huge.

Thus the resources spend for the one beamed downlink to the ground station are negligible in comparison to the thousands of unbeamed links to the a/c and ships. So why not use the "cheap" bandwith in the downlink to relay all data available to the ground.

BTW: Newer Aero-C Terminals have automatic doppler comensation. Aero-C - Products - Aero - - Thrane & Thrane (http://www.ttvms.com/sitecore/content/www,-d-,thrane,-d-,com/Aero/Products/Aero-C.aspx)
Maybe older terminals required assistance from the satellite for that compensation, which would explain, why the sat "knows" the speed of the terminal.

[sterion75]

The fire scenario has been mentioned before but if you think about the radar data indicating a climb to 4x000 feet then a sudden dive(Not sure if this information was validated or not)

Is that the move of a pilot trying to extinguish a fire? Has this happened and knocked out a lot of key systems

[lilkim]

No, the flight engineer doesn't work for MAS. He works for a private jet firm.

So the numbers still don't tally. :sad:

[JamesGV]

Nik4Me

I didn't know that.

There was mention of a "flight engineer" in the early stages.
He was Mohd Khairul working in private aviation as a Flight Mechanic.

The "13th" MAS employee onboard was a "Flight Engineer" ?

[Andy_S]

....the radar data indicating a climb to 4x000 feet ......

4x000 feet?????

Is that the move of a pilot trying to extinguish a fire?

This was speculated on several days ago, and an actual 777 pilot dismissed the notion as implausible.

[aviator1970]

Inmarsat uses 121.5/406.25 MHz tx to find out approximate position using Doppler shift... so why not any other frequency? Accuracy provided by the 406 fx is higher due to the higher frequency and hence more Doppler shift.... I make sense hopefully... or maybe Not...

[zamim]

One of the passengers was MAS staff based in Beijing.

[baba99]

Regarding the INMARSAT contribution, this is on their website:

Washington Post tracks Inmarsat role in hunt for MH370
[...]
The report added that the handshakes from the satellite – along with assumptions about the plane’s speed – helped Australia and the US National Transportation Safety Board to narrow down the search area to just 3 per cent of the southern corridor on 18 March.
(emphasis added)

It's not clear that what was announced today was anything beyond this?

[RichardC10]

A few days ago Capt Kremin pointed out that if the autopilot was in a mode that maintained a constant magnetic heading, there would be a significant turn to the East at the latitudes of Australia due to the large change in magnetic deviation. I looked at this in the context of the modelling that AAIB, NTSB and others are doing, to understand if the differences could be seen in the INMARSAT ping data that it is believed the authorities have. The answer seems to be not, as the two model tracks in the diagram (great circle in grey and constant magnetic heading in yellow) have very similar ping signatures with average differences of less than 15km (r.m.s. error) in the distances for each ping from the sub-satellite point. This may be less than the noise in the INMARSAT data. The two final southerly points of the tracks are 640km apart (one hour South of the last ping arc). Since a single search area was used by AMSA at the start of their activity, some method must have been used to decide between the track options.

Note: The only publically released data point on the map is the red final arc. The other ping arcs (only two shown) are just modelled results showing they match both tracks. The track direction is just an example that roughly matches the data in the AMSA maps.

http://i60.tinypic.com/2lwobo3.jpg

[JamesGV]

CodyBlade....

In these unprecedented circumstances when an official statement mentions pax as 226 and "colleagues" as 13, it would not be beyond reason to "query" the situation with regard crew ?

Especially when "openness" appears less than ...... "open" !

[oldoberon]

BABA99

Regarding the INMARSAT contribution, this is on their website:

Quote:
Washington Post tracks Inmarsat role in hunt for MH370
[...]
The report added that the handshakes from the satellite – along with assumptions about the plane’s speed – helped Australia and the US National Transportation Safety Board to narrow down the search area to just 3 per cent of the southern corridor on 18 March.
(emphasis added)

It's not clear that what was announced today was anything beyond this?

Of course it does it totally rules out the Northern arc' so they can say with a high degree of certainty all on board are now dead

[OleOle]

RichardC10

thanks for that work and the grasp it gives on the required error margin of the arcs. I would expect the great circle solution to turn to the right (west) when getting closer to the pole. Am i wrong or is the turn just too slight to see?

When going west over Malacca Strait in the first part of the track the a/c was heading always directly towards the satellite. Maybe from this part of the track inmarsat could put more constraints on speed.

Wind drift would also play a significant role.

----
Edit: Richards answer was, on southerly tracks and in lower latitudes great circles and rhumb (constant heading) lines are very similar. Wind drift for both solutions is similar too, and would not help to distinguish.

[awblain]

Richard,

Under similar assumptions does that rule out the Northern route? I assume that must require a weird combination of speed and track changes to remain consistent with the timings.

Neither the distance change away from the satellite between the hourly pings nor any potential Doppler information would by itself rule out a Northern location, any better than reasonable assumptions about the aircraft being spotted enroute ruled it out a week ago.

It's also not really clear why today's news, if the better Inmarsat analysis is all there's been, merits the appearance of the Malaysian PM or the move of the victims' families to Perth.

[DespairingTraveller]

@LLuCCiFeRp.s. how can the Malaysians now claim that the aircraft crashed into the Indian Ocean, when the aircraft disappeared off the radar and no wreckage has been officially found?

The Malaysians are not "claiming" anything. They are reporting the inescapable consequence of what they have been told by the UK AAIB and Inmarsat - both of them highly professional and competent organisations with no axe to grind in the matter. :ugh:

[Pontius Navigator]

I would expect the great circle solution to turn to the right (west) when getting closer to the pole. Am i wrong . . .

A line of longitude is a great circle. The yellow track, if I read it right is not a small circle.

The grey track is a rhumb line, ie a line of constant heading that cuts all lines of longitude at a constant angle.

[sterion75]

I just read that inmarsat said the altitude didnt change and it was 30,000+ constant(bbc)

[cockpitvisit]

Neither the distance change away from the satellite between the hourly pings nor any potential Doppler information would by itself rule out a Northern location,

From what I understood, the Doppler shift of interest was caused not by the aircraft movement, but by the slight movement of the satellite itself. So if the frequency increases when the satellite is moving "south", it means the airplane is in the Southern hemisphere.

But it could as well be a cover for a leak from spysats.

[RiSq]

I think a lot more info will come out over the next few days. It seems odd to me that they would announce it at this hour, if they didn't have additional info to back it up.

My hunch is that the crews went out with this "New info" today (local time) and found the wreckage, but details not released until they have a ship on the scene.

We know for certain that there has been a delay with all info, so the fact they announced it at this hour has me believe they have wreckage located that could only be from MH370.

Anyone else of same opinion?

Ps. Regards to fire, have they not confirmed the previously reported irratic altitude changes which had everyone assuming "fire" were incorrect and it held and maintained FL30?

[OleOle]

Pontius Navigator

A line of longitude is a great circle. The yellow track, if I read it right is not a small circle.
The grey track is a rhumb line, ie a line of constant heading that cuts all lines of longitude at a constant angle.

I understand that the grey line in Richards map represents the great circle. In the Mercator projection lines of constant heading are are straight lines. This case is special because we are getting close to the magnetic south pole where magnetic deviation rises to >30W. That is why the constant magnetic heading line (yellow in Richards map) turns to the east. Without deviation it would be a straight line in this projection.

[RichardC10]

OleOle
thanks for that work and the grasp it gives on the required error margin of the arcs. I would expect the great circle solution to turn to the right (west) when getting closer to the pole. Am i wrong or is the turn just too slight to see?

When going west over Malacca Strait in the first part of the track the a/c was heading always directly towards the satellite. Maybe from this part of the track inmarsat could put more constraints on speed.

Wind drift would also play a significant role.
The differences between a great circle and rhumb line are small for a track that is largely South and at these latitudes, and are hard to see at this scale. I looked at great circle, rhumb line and the constant magnetic bearing courses.

As you say, the final turning point to the Southly heading is not known and it might come out from analysis of the early ping data. Wind drift would be significant but would be the same for all tracks in roughly the same area so would not be a differentiator between the options, I think. Winds would be different on the possible North and South routes and could be one of the things that was used to rule out the Northly route.

[Dumbo Jet]

Thanks for the insight there. Couldn't work out how the doppler effect would help - but of course the satellite is also moving. Makes perfect sense now!

[RatherBeFlying]

If it hadn't been for Inmarsat, we'd still be looking from Somalia to Siberia.

And a very well done to the partnership with AAIB for resolving the ambiguity between arcs. There was some seriously caffeinated data crunching going on:ok:

Hopefully GPS location will be added to the ping ID. It won't stop suicides, but will give pause to those who thinking they can sneak off. With GPS data, any diverters will not be able to hide.

While in too many cases survivors will be unlikely, at least families will not be left in limbo -- to say nothing of the massive expenditures in search effort.

[Golf-Mike-Mike]

Richard, Under similar assumptions does that rule out the Northern route? I assume that must require a weird combination of speed and track changes to remain consistent with the timings.
Neither the distance change away from the satellite between the hourly pings nor any potential Doppler information would by itself rule out a Northern location, any better than reasonable assumptions about the aircraft being spotted enroute ruled it out a week ago. It's also not really clear why today's news, if the better Inmarsat analysis is all there's been, merits the appearance of the Malaysian PM or the move of the victims' families to Perth.

Because INMARSAT have also reviewed the pings from other Malaysian 777s that flew northerly routes and their doppler signature was different to that received from MH370. As that rules out a northerly track it places the missing aircraft in the southern Indian Ocean, without a landing site anywhere near, and hence the need to tell the families that there is now no hope of survival.

[ edit to add this, from BBC - Engineers spent all weekend looking back at previous Malaysian Airlines Boeing 777 flights, going back several weeks.
They compared the satellite data from those flights with flight MH370 and were able to work out it went south.
This is cutting-edge modelling, never tried before. It uses the Doppler effect - which is what makes a police siren sound different from different points.
They had it reviewed by other scientists before handing it over.
As far as they can tell, the plane was flying at cruising height, above 30,000ft. They found no evidence of fluctuating heights being reported.
This is it now - they cannot pinpoint the position any further. They handed this data over on Sunday morning. ]

[AndyJS]

The latest estimates seem to indicate that the plane may have flown over Indonesian airspace. But they didn't notice?

[NigelOnDraft]

Hopefully GPS location will be added to the ping ID. It won't stop suicides, but will give pause to those who thinking they can sneak off. With GPS data, any diverters will not be able to hide.

While in too many cases survivors will be unlikely, at least families will not be left in limbo -- to say nothing of the massive expenditures in search effortNot too sure about this I'm afraid. This accident has ensured any future plan will involve isolating the Satcom units themselves as well, not just the protocols that use it.

[G0ULI]

Excellent work by the AAIB. So we now know the aircraft flew at steady speed and altitude until the fuel ran out in the Southern Indian Ocean. That should at least put paid to all the posts relating to Lithium battery fires, flying under the radar and deliberate attempts to kill everyone by hypoxia/anoxia. The most obvious conclusion is that someone was in control of the plane until it crashed. Clearly the anti hijack door functioned exactly as advertised and prevented anyone from entering the cockpit once the course to the Southern Indian Ocean had been set. A tribute to the cockpit security system installed on this aircraft.

[Dumbo Jet]

I'm sorry but how do you KNOW that? Would be interested to know your factual evidence for that!

[DAL208]

From memory, the southern 'arc' started to the south of the last known position of the aircraft. Is it not possible the aircraft didn't turn left over malaysia at all and just went South from its last known position? Could the primary RADAR contact be completely different aircraft? How certain are we it turned left and went over straits of malacca?

[funfly]

BBC reported said (1830) that he asked the spokesman if there was any more information on the cause and the reply was that they had some additional information but were not ready to announce it.

[Captain_Bolt]

The sheer ingenuity required for this level of work has amazed me beyond belief.

Fantastic work by Inmarsat and the AAIB.

[G0ULI]

Dumbo Jet
I know that the INMARSAT and AAIB boffins have the technical and mathematical skills to carry out the signal analysis to determine the details published. That being the case, the obvious conclusion is that the aircraft was deliberately flown until the fuel was exhausted. If it had been possible for someone to enter the flight deck, then surely some attempt at communication would have been made and the aircraft would not have crashed into the sea.

[DAL208]

Just because it doesn't make sense doesn't mean it didn't happen. How many times have we seen unusual things happen in accidents as a result of the situation?

Surely AFR447 shows this? !

[funfly]

INMARSAT stated on the BBC news that remote monitoring was already mandatory on seagoing vessels and was totally practical for aircraft, he claimed it could be introduced for 1$ per flying hour.

[nippysweetie]

Well, while all the guesswork goes on amongst PPRuners, in Beijing, victims' relatives are quite clear who is to blame for this set of events... 'executioners', if you will. Statement as follows:

"At 10pm on March 25, the Malaysian prime minister sent a statement to the families of MH370 passengers without any direct evidence that MH370 crashed in the south Indian ocean and no people survived.
"From March 8 when they announced that MH370 lost contact to today, 18 days have passed during which the Malaysian government and military constantly tried to delay, deceive the passengers' families and cheat the whole world.
"This shameless behaviour not only fooled and hurt the families of the 154 passengers but also misguided and delayed rescue actions, wasting a large quantity of human resources and materials and lost valuable time for the rescue effort.
"If the 154 passengers did lose their lives, Malaysia Airlines, the Malaysian government and military are the real executioners who killed them. We the families of those on board submit our strongest protest against them.
"We will take every possible means to pursue the unforgivable crimes and responsibility of all three."

[atakacs]

If (and at this stage it still is a big IF) the plan was to crash the plane in the most remote part of the world could a flight east towards the Pacific have been possibly even more appropriate ?

[Golf-Mike-Mike]

Dumbo Jet
I know that the INMARSAT and AAIB boffins have the technical and mathematical skills to carry out the signal analysis to determine the details published. That being the case, the obvious conclusion is that the aircraft was deliberately flown until the fuel was exhausted. If it had been possible for someone to enter the flight deck, then surely some attempt at communication would have been made and the aircraft would not have crashed into the sea.

Yes that may be one obvious conclusion but hopefully the NTSB / AAIB / Malaysian / French investigators retain open minds; for example that all comms and pilots could have been wiped out by an event as yet unknown and it flew itself to its final resting point.

[MG23]

How certain are we it turned left and went over straits of malacca?

If that turn was inconsistent with the earliy satellite data, someone would have pointed it out by now. Obviously, merely being consistent doesn't mean it did make that turn, but tends to support that theory.

[offa]

Nightingale said: Maybe some of us are doing the captain an injustice. The cargo information is hazy. (Latest reports say the Malaysians are declining to provide the manifest to the Australians without a formal written request.) Let us not forget the plane was flying to Beijing. Maybe there was something "sensitive" on board for the Chinese government and the Malaysians need to clear this with China before releasing the information. Maybe one or more passengers had got wind of this cargo and tried to hijack the plane to make demands against release of the cargo. The captain and FO were forced to turn off the signals but managed to turn south before they were killed. Then there was no-one left to fly the plane so it continued on auto pilot until it crashed into the Indian Ocean. Well it is no crazier than any of the other theories being put forward here"

I think you are spot-on ..... in response to a catastrophic fire caused by e.g. the Li-Ion batteries being carried as cargo. If these were in the forward cargo they could have affected electrical busses in close proximity resulting in loss of ACARS and transponder as well as radios.
It would be perfectly normal under such circumstances to don O2 masks and select heading back towards the nearest suitable airport (KUL or Phuket?) then FLCH to descend the aircraft to FL120 while trying to communicate (unsuccessfully) and avoid breathing acrid fumes. Oxygen bottles could have overheated from a fire and blown out so no O2 supply for the crew.
The aircraft turns onto the selected heading and descends to FL120 at the selected speed. It levels off and continues flying on the same heading at FL120 and maintaining e.g 280 knots until it runs out of fuel and glides at 280 knots into the ocean.
Do the maths using the FPM at FL120 and 280 knots or thereabouts but I wish these so-called "experts" would leave the crew and their poor families out of it unless they have any concrete evidence otherwise.
(Remember LI-Ion batteries carried as cargo brought down a brand new 747-400 in Dubai in 2010. The crew were completely incapacitated and unable to fly the aircraft in daylight and in contact with ATC)

[olasek]

The aircraft turns onto the selected heading and descends to FL120 It has been reported that the alleged descent to FL120 never occurred.

The crew were completely incapacitated and unable to fly the aircraft in daylight and in contact with ATC)Vastly different circumstances, the pilots were able to talk to ATC and flight ended very quickly (minutes), not flying for 7 hrs across oceans and making funny turns avoiding airspaces.

[olasek]

No proof of fuel exhaustion. well, there is almost a proof.
They had fuel for 7:30 hrs and the flight lasted over 7 hrs.
In view of the above it is you who has to prove there was no fuel exhaustion.

[James7]

Gouli ... . That should at least put paid to all the posts relating to Lithium battery fires, flying under the radar and deliberate attempts to kill everyone by hypoxia/anoxia

If someone was alive in the cabin then the portable ELT's would have been activated.

[airsupport]

RAAF confirming here this morning that they have now found debris from the aircraft, sadly no survivors.

[olasek]

RAAF confirming here this morning that they have now found debris from the aircraft
And your sources are ...??

[MPN11]

If someone was alive in the cabin then the portable ELT's would have been activated. By whom? Someone who knew they were there, and how to operate them? A random passenger, perhaps?
"If the 154 passengers did lose their lives, Malaysia Airlines, the Malaysian government and military are the real executioners who killed them. We the families of those on board submit our strongest protest against them.
"We will take every possible means to pursue the unforgivable crimes and responsibility of all three.""Someone doth protest too much, methinks"

Now back to credible News.

[Lonewolf_50]

RAAF confirming here this morning that they have now found debris from the aircraft, sadly no survivors.
Has it hit the media yet?

[DCrefugee]

The following conclusions reached by the BEA after its search for AFR447 may be of interest:

- Above all, more frequent position reporting by aircraft is required (flight AF 447 transmitted its position every 10 min). This is the subject of a recommendation made by the BEA in its Interim Report n° 2 on 17 December 2009.
- Drift buoys must be released as soon as possible after any accident, in order to follow the drift currents, which can be highly unpredictable beyond a few days.
- Calling on a submarine to listen for acoustic beacon signals at 37.5 kHz is not appropriate.
- The transmission times of acoustic beacons must be increased from 30 to 90 days: despite this, it is noted that there is some doubt as to whether they functioned. The recommendation made by the BEA to install an additional beacon, transmitting on a lower frequency and thus with longer range, should enable the risk of non-detection to be decreased.
- The Remus AUV, equipped with sonar and camera, proved themselves to be highly effective.
- Exploring undersea areas with rough terrain at great depths and so far from the coast is a technological and organisational challenge. It takes a long time to organise such operations, which call on resources in material and the few world specialists, and need significant financial resources (from 5 to 15 M€).

[hamster3null]

This latest announcement makes zero sense to me physically. The talk about Doppler effect looks like techno-gibberish that makes me wonder what exactly they are hiding and why.

We have a radially symmetric configuration. One satellite in geosynchronous orbit, approximately round Earth, and an aircraft somewhere above the Earth. We can measure the distance from the satellite to the aircraft via time-of-flight, and we can measure the radial speed of the aircraft via Doppler effect, but nothing here breaks either the rotational symmetry or mirror symmetry.

[Seabreeze]

RAAF cannot confirm debris is from MH370 by visual means alone. Need debris in hand to confirm.

[Golf-Mike-Mike]

This latest announcement makes zero sense to me physically. The talk about Doppler effect looks like techno-gibberish that makes me wonder what exactly they are hiding and why.

Already posted that they said they went back through weeks of other Malaysian 777 flights they had data for and examined the signal for those going northbound compared to the southbound ones and saw a Doppler shift (I guess?). So they're making a comparison not looking at MH370 alone.

similarly no talk of "jitters" I read in another thread.

[Doc Savage]

:cool:

FWIW, here is a little more detail on what the RAAF saw as reported be the pilot (per Xinhua):


RAAF says mutiple objects "verified", mission deemed "successful" - Xinhua | English.news.cn (http://news.xinhuanet.com/english/world/2014-03/24/c_133210588.htm)

[Chronus]

Lonewolf 50

According to latest on our side of the pond is the Malaysian PM`s announcement, compassionate and commiserating in nature rather than hard facts. The RAAF P3 crew have reported floating objects which appear to be a crate and belts. So nothing concrete as yet.
Good chance by early tomorrow the reported debris may be recovered by vessels in the area and promptly identified.

[hamster3null]

Already posted that they said they went back through weeks of other Malaysian 777 flights they had data for and examined the signal for those going northbound compared to the southbound ones and saw a Doppler shift (I guess?). So they're making a comparison not looking at MH370 alone.

similarly no talk of "jitters" I read in another thread.

Satellite sees a Doppler shift when the aircraft is on a trajectory that brings it closer or further away from it. E.g., if the satellite is 45 degrees above the horizon from the point of view of the aircraft and the aircraft flies at 490 knots and steady altitude directly towards the satellite, and communications between the satellite and the aircraft occur at the frequency of 1.6 GHz, Doppler shift is 1.6e9*cos(45)*(490*1.852/3600)/299792=1903 Hz.

If the same aircraft were to turn either X degrees left or X degrees right, radial speed (the component directed towards the satellite) would decrease, transverse speed would increase, and Doppler shift would decrease. But, since the system has mirror symmetry, the satellite has no way of knowing whether the aircraft turned left or right.

Like I said, we have a highly symmetric configuration (one satellite) and nothing evident to break the symmetry.

[Ornis]

hamster3null The talk about Doppler effect looks like techno-gibberish ... We have a radially symmetric configuration.

Different surfaces north and south: land and ocean?

[Sober Lark]

I thought Chris McLaughlin of INMARSAT certainly had a dig at MAS this evening for being one of the airlines who choose not to follow the AF447 BEA recommendation 4.2.4 relating to transmission of flight data and who are now suffering the consequences of such inaction.

[Machinbird]

This latest announcement makes zero sense to me physically. The talk about Doppler effect looks like techno-gibberish that makes me wonder what exactly they are hiding and why.Hamster,
Supposing the orbit of the satellite were ever so slightly inclined to the equator. Then the satellite would appear to nutate North and South of the equator as viewed from earth and would create slight doppler effects at certain times of the day for stations essentially North and South of the satellite. Gotta be something like that.

[daikilo]

I have just listened to the BBC interview of a person from INMARSAT. If I understood correctly
1) they did create and provide a model of the likely "disappearance" zone about a week ago i.e. over a week after the event, based on analysis of pings and modelling of typical MH flights. Congratulations for the initiative to what is in principle a data-transmission organisation.
2) as search organisations did then go to the area, it is also logical that the Malaysians would want to also remain focussed on other scenarios until they had been rendered impossible. Had they not done so and had the Inmarsat model have subsequently been proved wrong would have been unfortunate.
If I add to that
3) as far as I have been able to ascertain, there is no firm evidence of what happened inside the plane after the last voice exchange
4) likewise there is little evidence of where it actually then flew and even less on how it got onto the track it seems to have followed, or for that matter any other possible tracks
I find the statement emanating from the Beijing family group very unfortunate and possibly due to a lack of counselling and understanding of the bigger picture. It is imperative that the industry works to communicate on why it takes time and thus avoid such happenings. That said, I have to admit that the comment of the Inmarsat responsible that, by obligation, ships are tracked every 6 hours and that a similar tracking could be instituted for aircraft blew me over, not by its simplicity, but by the fact that say ICAO has not mandated it. I hope they will see the value. We don't need another one like this.

[catch21]

Perhaps there's an air temperature or humidity difference between the N & S arcs that would make differentiation possible? Land & sea and all that? I appreciate the altitude involved here.

[Golf-Mike-Mike]

Satellite sees a Doppler shift when the aircraft is on a trajectory that brings it closer or further away from it. E.g., if the satellite is 45 degrees above the horizon from the point of view of the aircraft and the aircraft flies at 490 knots and steady altitude directly towards the satellite, and communications between the satellite and the aircraft occur at the frequency of 1.6 GHz, Doppler shift is 1.6e9*cos(45)*(490*1.852/3600)/299792=1903 Hz.
If the same aircraft were to turn either X degrees left or X degrees right, radial speed (the component directed towards the satellite) would decrease, transverse speed would increase, and Doppler shift would decrease. But, since the system has mirror symmetry, the satellite has no way of knowing whether the aircraft turned left or right.
Like I said, we have a highly symmetric configuration (one satellite) and nothing evident to break the symmetry.

So are you saying if you compare the Doppler shift in MH370's pings, over a 7hr flight on a SSW track, with flights flying in some opposite direction, would there be no difference whatsoever ?

[UnreliableSource]

I was one of those who questioned the Inmarsat ping results. The constant 40deg angle running near KL seemed questionable.

Now that the techniques have been validated against multiple aircraft, my hypothesis (terminal tracked not aboard aircraft) is clearly disproved.

Full marks to those who crunched the data. Your work has helped bring closure to this tragic matter.

[albatross]

After what has gone on in the last weeks I think that the RAAF would not say they had wreckage identified until they had it in hand and positively identified - even if it was a large chunk.
Just imagine the reaction if they this based only on a sighting and then were proven to be mistaken or couldn't recover it.

[TelcoAg]

To those questioning the Doppler shift analysis, and trying to rationalize how you could determine a north vs south heading, it's pretty simple. You are analyzing this as if the pings started on the equator, which we know they didn't. If part of the readings indicated the plane was getting closer before it was going away from the satellite, then it was heading south west. If all of the readings indicated the plane was getting father away, then it would be going north.

The fact that the plane didn't start on the equator is what breaks symmetry.

[G0ULI]

TelCoAg
Exactly the case. Also the satellite moves slightly around an average orbital position which also contributes additive and subtractive doppler effects which break the directional symmetry if sensitive enough measurements can be made.

[mm43]

The INMARSAT 3-F1 is in a geostationary orbit above the earth at a nominal 35786km distance. At that nominal height its orbital speed enables it to remain stationary over the Equator and at 64.5°E. However, as the satellite is geosynchronous with a small offset to allow it to remain geostationary, causes its position both in distance above the earth and its nominal position, to change over a period of 1 siderial day (23.934 hours). This positional change is a small ellipse with a 1.6580° inclination that extends 1.59° north and south of the Equator in a very skinny figure of 8 shape.

The fact the eccentricity is predominately N and S has presented the possibility of determining the values of small doppler shifts in a signal being received from an aircraft that is either traveling N or S below it.

http://oi57.tinypic.com/11vpauf.jpg

The above was extracted from http://www.n2yo.com/?s=23839 as the satellite had just started moving south in its eccentric ellipse.

The satellites eccentric speed (in relation to its Earth position) as it passes over the Equator every 11.97 hours is approximately 90m/s. This provides no Doppler shift effect to an observer directly below it, but the Doppler shift will become more evident the further N or S the earth observer is located.

[brika]

.hurt the families of the 154 passengers...

..now where did you get 154 passengers from?

The official count is 129 passengers and crew!

If you cannot get your facts right please do no post.:=

Correction - 239, not 139. pointed out by Lonewolf 50. Thank you.

Every one of the 239 passengers had family and everyone of those families are hurt, not just the Chinese. Let's not bring a racial tone into this please.

[Lonewolf_50]

..now where did you get 154 passengers from?

The official count is 129 passengers and crew!

If you cannot get your facts right please do no post.:=
239 total, from most reports. ;)

The 154 figure is how many people on that aircraft were from China (http://www.pprune.org/rumours-news/535538-malaysian-airlines-mh370-contact-lost-395.html#post8398644).

"This shameless behaviour not only fooled and hurt the families of the 154 passengers but also misguided and delayed rescue actions, wasting a large quantity of human resources and materials and lost valuable time for the rescue effort.

"If the 154 passengers did lose their lives, Malaysia Airlines, the Malaysian government and military are the real executioners who killed them. We the families of those on board submit our strongest protest against them. "We will take every possible means to pursue the unforgivable crimes and responsibility of all three." The lawyers have arrived on scene, needless to say, but I don't know the exact head count. :p

[MPN11]

154 Chinese, perhaps? Which adds a certain dimension to the whole event.

[brika]

Quote:No proof of fuel exhaustion.

No converse proof either.

However, point of fuel exhaustion calculated by estimated fuel load has been calculated....search areas appear to coincide as well.

[hamster3null]

The fact that the plane didn't start on the equator is what breaks symmetry.

There's still symmetry about the line connecting the starting point and the "epicenter" of the satellite (0N 64.5E).

The fact the eccentricity is predominately N and S has presented the possibility of determining the values of small doppler shifts in a signal being received from an aircraft that is either traveling N or S below it.

OK, this is more interesting. Satellite drift by itself does not break the symmetry, but speed of the satellite wrt surface of the Earth would either subtract from speed of the aircraft if it moves in the same direction, or add to it if it moves the other way. I suppose this could work.

[DX Wombat]

MPN11 "Someone doth protest too much, methinks"That remark is unreasonable, these are deeply traumatised people who have just had their worst fears confirmed beyond any doubt and are trying to make some sense of it all.

Hamster3nul
The talk about Doppler effect looks like techno-gibberish that makes me wonder what exactly they are hiding and why.
Do not be so insulting about the AAIB, the best aircraft accident investigation service anywhere. The AAIB does not publish rubbish or write its conclusions to satisfy somebody's whims, it reports facts and you can be absolutely certain that, to quote G0ULII know that the INMARSAT and AAIB boffins have the technical and mathematical skills to carry out the signal analysis to determine the details published. and if they came to the conclusion which they published then that IS the conclusion. If you know better than the AAIB the you should let them know. However, I'm not that sure they would believe you after all, you didn't find the aircraft's track and position. The AAIB might just have a quiet giggle.

[TelcoAg]

There's still symmetry about the line connecting the starting point and the "epicenter" of the satellite (0N 64.5E).

While true in a 2 dimensional analysis, you ignore the curve of the earth, which makes the line of symmetry follow along the equator.

[Robin Clark]

........nice info on the satellite from MM43 and the others . .........can I just add that the system is not nearly as symmetrical as you might think..the earth is not a sphere and has an equatorial bulge due to spin .....the earth and moon act as a binary system in orbit around each other , so the actual centre of gravity of the "system" is some 4000km away from the centre of the earth in the direction of the moon , it causes a slight bulge on the surface of the earth , and the tides too........so any item in orbit around the earth has a bit of a balancing act to perform.....

[Tarq57]

Anybody know how good (re sensitivity and attention-getting) the carbon monoxide detector/s on this a/c are?

Done a thread and forum search. The word "monoxide" doesn't appear in this thread, according to the search result.

[VinRouge]

Robin, the local gravitational effects you mention don't affect geostationary sats.

[Flymach8]

As with the SilkAir incident, I'm convinced that this will be found to be pilot murder/suicide.

ACARS, Transponder turned off and I'm sure the DFDR and CVR will be found turned off in due course.

[VinRouge]

Assuming the FDR hadn't been disabled at he same time as the comms.

Is there an sfdr cb?

Telegraph reporting flight investigators considering 'suicide mission' and jet was deliberately crashed. :(

If I was the co, there is no fekking way that door would be standing after 7 hours, even if I had to use a fire axe to chop my way through the forward bulkhead.

[barit1]

Several years back in another thread, there was a reference to an optional FMS feature addressing the emergency descent case. IIRC it was autonomous - rapid decompression would cause a 90 degree turn and max rate descent.

I've not been successful in tracking this down via PPRUNE search. Any ideas?

[500N]

" Telegraph reporting flight investigators considering 'suicide mission' and jet was deliberately crashed. :("


Media speculation, trying to hype a story.
EVERYTHING will be on the table as to cause.

[tangolimasierra]

Ok, like everyone else I feel for the families of those who have lost their lives. But I do have to say something about the attitude of the relatives, if the reports of the behaviour is true. No matter what happened on that airplane, the behaviour of the Chinese relatives and their disrespect to the Malaysian authorities is disturbing. I am willing to wager that they would not have acted this way towards their own government if it had been a Chinese aircraft. The Malaysian government may have made some mistakes in the presentation of information, but I do feel that they were trying to do they best in very difficult circumstances. I have been very impressed by the Defence Minister and Acting Minister of Transport and I have never previously been one to praise members of that particular government.

[oldoberon]

I was one of those who questioned the Inmarsat ping results. The constant 40deg angle running near KL seemed questionable.

Now that the techniques have been validated against multiple aircraft, my hypothesis (terminal tracked not aboard aircraft) is clearly disproved.

Full marks to those who crunched the data. Your work has helped bring closure to this tragic matter.

that is good of you to say so, hope others follow.

[offa]

Source: Flight 370's altitude dropped after sharp turn Kuala Lumpur, Malaysia (CNN) -- As a growing number of airplanes scoured the southern Indian Ocean in the search for Malaysia Airlines Flight 370, authorities released new details that paint a different picture of what may have happened in the plane's cockpit.
Military radar tracking shows that the aircraft changed altitude after making a sharp turn over the South China Sea as it headed toward the Strait of Malacca, a source close to the investigation into the missing flight told CNN. The plane flew as low as 12,000 feet at some point before it disappeared from radar, according to the source.
The sharp turn seemed to be intentional, the source said, because executing it would have taken the Boeing 777 two minutes -- a time period during which the pilot or co-pilot could have sent an emergency signal if there had been a fire or other emergency onboard.
Authorities say the plane didn't send any emergency signals, though some analysts say it's still unclear whether the pilots tried but weren't able to communicate because of a catastrophic failure.

[Unixman]

Could someone just run the following bit of physics past them to see if I have got the important point about the Doppler shift right?

If the satellite was absolutely fixed then the Doppler shift would be the same irrespective of whether the plane was heading north or south BUT the sun and moon cause a slight - but predictable - wobble in the orbit of the satellite and since that wobble is also N/S that will add a very small but measurable extra value in the existing Doppler shift. If the satellite was heading south at the same time as the plane then the Doppler effect would be squeezed by a tiny bit and the wavelength decreased - ie very slightly blue-shifted. If the satellite was moving north whilst the plane was heading south then the radio wavelength would be stretched - very slightly red shifted.

Have I got that correct ?

[LegallyBlonde]

Confirmation of pax and crew numbers -

On behalf of all of us at Malaysia Airlines and all Malaysians, our prayers go out to all the loved ones of the 226 passengers and of our 13 friends and colleagues at this enormously painful time.

MH370 Flight Incident | Malaysia Airlines (http://www.malaysiaairlines.com/my/en/site/dark-site.html)

Passenger manifest -
http://www.malaysiaairlines.com/content/dam/mas/master/en/pdf/Malaysia%20Airlines%20Flight%20MH%20370%20Passenger%20Manife st_Nationality.pdf

[mm43]

If the satellite was heading south at the same time as the plane then the Doppler effect would be squeezed by a tiny bit and the wavelength decreased - ie very slightly blue-shifted. If the satellite was moving north then the radio wavelength would be stretched - very slightly red shifted.

Have I got that correct ?That is correct.:ok:

[VinRouge]

Doppler was mentioned 10 days ago on here, was discounted as a location technique, together with the South Indian Ocean location they have probably found the jet in as tin foil hat conspiracist theory.

It wa postulated that the jet would be found either close in or at max range.

[VinRouge]

Would the 406 ELT work inside a faraday cage, with no ability for gps signal reception or comms with sarsat?

[Pontius Navigator]

Would the 406 ELT work inside a faraday cage, with no ability for gps signal reception or comms with sarsat?

If a cell phone works . . .

We have once been alerted to an emergency beacon on 243MHz. It turned out to be one of our own so that signal had certainly escaped the cage.

[GQ2]

Currently, we still know almost nothing FACTUAL about this incident. There has been some outstanding comment and contribution in this thread. There are a lot of theories, but also, a lot of hot air from many who know nothing and some who should know better. There have been numerous idiotic comments in this thread blaming the crew, directly or indirectly. Since most of the so-called 'facts' implicating the crew seem to have faded-away, along with much else, it is simply unacceptable to post as though this was a done-deal. It ain't, - not by a long way. It's just one of a whole bunch of theories as yet.
This has been an unprecedented incident, and the causes, effects and remedies will gain no clarity whatsoever by unjustly and prematurely implicating the crew. Please desist, it's embarrassing :=

[777fly]

If this was a case of unlawful interference, someone obviously wanted this aircraft to disappear and/or ensure that there would be no survivors. Perhaps it would be worth checking who on board had taken out high or unusual life insurance.

[syseng68k]

Unixman:

Let's try an example: Assume that the satellite is directly above the equator, also that the a/c is north of the equator and flying south.

As the a/c approaches the equator, doppler effect will cause an increase in measured frequency of the return signal in relation to the transmitted as the a/c effectively becomes closer to the satellite. This drops to zero offset as the a/c passes under the equator. Past the equator, the frequency will decrease as the effective distance from the satellite increases.

You can only get a 1d point fix from one satellite, but a 2d fix may be possible with two, depending on available data...

[hamster3null]

Could someone just run the following bit of physics past them to see if I have got the important point about the Doppler shift right?

If the satellite was absolutely fixed then the Doppler shift would be the same irrespective of whether the plane was heading north or south BUT the sun and moon cause a slight - but predictable - wobble in the orbit of the satellite and since that wobble is also N/S that will add a very small but measurable extra value in the existing Doppler shift. If the satellite was heading south at the same time as the plane then the Doppler effect would be squeezed by a tiny bit and the wavelength decreased - ie very slightly blue-shifted. If the satellite was moving north whilst the plane was heading south then the radio wavelength would be stretched - very slightly red shifted.

Have I got that correct ?

Sun and moon gradually deform the orbit of a satellite in a geostationary orbit, causing it to "wobble" N/S daily unless the satellite spends fuel to correct. Most satellites do this periodically. If you look here List of satellites in geostationary orbit (http://www.satsig.net/sslist.htm) most satellites have "inclination" (wobble amplitude) of <=0.1 degrees. (If the satellite is left on its own, its inclination is going grow ~1 degree per year.) Fortunately for us, Inmarsat-3 F1 is an old satellite (launched in 1996 and the second oldest Inmarsat satellite in orbit), which means that it must be running out of fuel, which means that its owners are probably trying to conserve fuel and skipping N/S compensation maneuvers. It has inclination of 1.6 degrees.

The rest is correct.

[albatross]

I once had a passenger ELT activate accidentally.
((helicopter offshore ops) everybody has one plus the 2 on the helicopter, one jettisoned by impact or manually, plus the 2 in the rafts))
We could hear it but one of our helicopters less than 20 NM away could not.
I presume that the 777 fuselage is much "thicker" re radio emissions than a helicopter so perhaps an ELT activated within with no external antenna would not be picked up by SARSAT.

[henra]

IF, and I say IF, this turns out to be an event managed from within the flight deck secure door and it ran its full course to the Southern Ocean without passenger incapacitation, then it must have been utter and unimaginable bedlam in the cabin for 7 hours.


It is hardly conceivable the door would be able to resist desperate and unhindered attempts of the Pax/CC to open it forcefully for 7 hours.
Crash axe and/or stuff from the galley or the cabin itself in the hands of multiple desperate People fighting for their lives would surely finally take its toll on the door and/or the floor.

It is therefore rather likely that at least in the latter phases of the flight no one in the cabin was conscious. Potentially in front of the door no one either.

What caused this is the big mystery for which we can only hope the CVR/FDR to be found and readable.

[NWSRG]

As a one time PPL and regular SLF, I have not posted up to now, as I have no authority to discuss the matters at hand. Some of the technical input from the professionals on the site has, however, been incredible...and testimony to their knowledge.

So I'm not about to begin speculation, rather ask one question, and pose another. Firstly, if they are recovered, will the on board recorders offer any useful data? I ask this as I understand (maybe wrongly) that they overwrite after some time.

Secondly, given that it has taken (at least publicly) two weeks for the authorities to locate MH370, is now the time to mandate real-time location transmission? Had this been available for MH370, the military could have intercepted the aircraft in the early stages of their deviation from flightplan...if not to prevent anything, at least to understand it.

Whatever happened, I hope the poor souls on board were unaware of their fate.

[Lonewolf_50]

Firstly, if they are recovered, will the on board recorders offer any useful data?
The flight data recorder should provide much useful information.
I ask this as I understand (maybe wrongly) that they overwrite after some time. The typical Cockpit voice recorder overwrites every 2 hours or so. (Last one I looked up was 2.5 hours)
Secondly, given that it has taken (at least publicly) two weeks for the authorities to locate MH370 --
Nothing confirmed has been found, in terms of floating debris. If such debris is confirmed, the actual hunt for the aircraft begins. That will take more time.
, is now the time to mandate real-time location transmission? IMO, no. Other opinions will differ. Automobile designers are not required to design their cars for the cases of people who run them off of cliffs. I see no reason, given how many flights take off and land each day the world over by people using aircraft for their intended purpose, to make such a rule when a great deal of tech is already required and installed to keep track of where aircraft are and are going.
Since it has not been confirmedHad this been available for MH370, the military could have intercepted the aircraft in the early stages of their deviation from flightplan...if not to prevent anything, at least to understand it. The military from what nation?

[mickjoebill]

Media reports said last night that there are "no survivors".

The Prime Minister's statement and Malaysian Airlines statement did not state that there are "no survivors".

They said the "flight was lost" and the PM's statement and condolences were certainly downbeat to reflect the probability that all have perished.

[NWSRG]

Thanks Lonewolf...

The military from what nation?

I'm assuming the Malaysians themselves would have taken an interest...given the initial track back towards Malaysia, without any comms.

IMO, no. Other opinions will differ. Automobile designers are not required to design their cars for the cases of people who run them off of cliffs. I see no reason, given how many flights take off and land each day the world over by people using aircraft for their intended purpose, to make such a rule when a great deal of tech is already required and installed to keep track of where aircraft are and are going.

A fair point...but for me, two factors would sway it the other way. First, the number of lives on board a 777. Second, the damage that aircraft can potentially do.

[oldoberon]

What could the military do

Shoot it down quicker end I suppose and more chance of finding fdr/cvr with 100+ chinese om board would have thought there would have to be agreement by which time out of fighter range.

If not an accident and perpetrators conscious might end up with a nose dive and accusations that the military had forced the end.

Can't see they could force it down or help it down.

[DaveReidUK]

They had fuel for 7:30 hrs and the flight lasted over 7 hrs.
In view of the above it is you who has to prove there was no fuel exhaustion.

Demonstrating that there is an absence of proof for a hypothesis does not necessitate having to prove the opposite.

[kiwiflyguy]

...would the cabin crew have activated one of the ELTs especially if they found the biz class sat phones were not functioning?

Having been cabin crew for 10 years with a few different carriers (Asia / Pacific) the use of portable ELT was never taught in initial nor recurrent training as an "onboard" device. Before I read this post it never crossed my mind to use it in flight. We had extensive training about setting the ELT at a high point on land (survival scenario) or its use in water, but I have never contemplated the use on-board an aircraft.

I am not sure that a crew member on MH370 would have thought of that either given the varying scenarios.

I'm sure that given the outcome of the investigation there will be mandated changes for not only tech crew but also cabin crew too.

Cheers for the insight. Might have to incorporate that into a briefing!

[NWSRG]

What could the military do

Provide information. Prepare those on the ground. Help locate the aircraft when it does come down. Take images that might help identify the root cause.

Surely getting eyes on the aircraft could only be beneficial...

[VH-XXX]

A good graphic that appeared today in news.com.au

http://media.news.com.au/nnd//d08e05ad779ffd764a70287b8cca224c/desktop/assets/wreckage-location.png

[500N]

Something would wash up, on the West (or possibly South) coast of Aus IF it crashed where they are searching.

[Machinbird]

We may never see the DFDR.Yes, and if we do, there may be no data on it.
Someone might have pulled the C/B to shut it down.:suspect:

[Doc Quag]

Sky News reporting that SAR efforts stood down for today due to bad weather.

[Golf-Mike-Mike]

Sky News reporting that SAR efforts stood down for today due to bad weather.

Yes, quote from AMSA press release dated 25th March..
AMSA has undertaken a risk assessment and determined that the current weather conditions would make any air and sea search activities hazardous and pose a risk to crew. Therefore, AMSA has suspended all sea and air search operations for today due to these weather conditions.

[TerryB]

AMSA has advised that the search has been postponed for today due to bad weather in the search area. No planes flying and the Success has left the immediate area because of the weather.

"Due to rough seas, HMAS Success departed the search area early this morning and is now in transit south of the search area until seas abate. A sea state ranging between 7 to 8 is forecast today with waves up to two metres and an associated swell of up to four metres.
The area is also forecast to experience strong gale force winds of up to 80km/h, periods of heavy rain, and low cloud with a ceiling between 200 and 500 feet."


The Success was not able to locate either of the items spotted by the Orion yesterday (and with that weather forecast you can assume they are not going to be anywhere near where they were by the time the weather improves.

[TerryB]

Something would wash up, on the West (or possibly South) coast of Aus IF it crashed where they are searching.

Doesn't mean it will be found anytime soon - most of the west and southern coasts of Australia are pretty isolated places so something could wash ashore and not be found for years.

[Fubaar]

Slats11, the new doors fitted post 2001 would withstand automatic gunfire.

[25F]

This is costing the Chinese massively in Satellite resources.

Photo reconnaissance satellites typically follow a polar orbit. This goes over both poles, whilst the earth rotates underneath, so they spend equal amounts of time in the northern and southern hemispheres.
The timing of the orbits puts them over their targets early in the morning or late in the afternoon, in sun synchronous orbits, to get 3D perspective.
To change orbit to look at a different target uses up manoeuvre fuel. They obviously only have a finite amount of this so using it is incredibly expensive in terms of the life of the satellite.

About 50% right by my reckoning. They do follow sun-synchronous polar orbits. This gives them global coverage. So they are not "targeted". Hence no fuel used to change orbit.

Yaogan-19 is apparently a recently-launched Chinese spysat:Launch News Long March 4C launch with Yaogan 19, November 20, 2013 - Orbiter-Forum (http://www.orbiter-forum.com/showthread.php?t=32704)

Here's a list of times and inclinations for its passes with respect to 42S 95E which is more or less where they've been looking.
YAOGAN 19 - All Passes (http://heavens-above.com/PassSummary.aspx?satid=39410&lat=-42&lng=95&showall=t)

(As far as I know the site mixes historically accurate information with predicted passes).

You'll see that it flew directly overhead at 16:47 (UTC) on the 21st March. Also that it is predicted to do so at 16:47 on the 28th of March; and that it did so at 16:47 on the 14th of March, and the 7th, and so on, going back for months.

No changes in orbit.

(NB that it goes *directly* overhead once per week, but that every day there will be at least one pass where it is reasonably high in the sky).

[James890]

A lot earlier in this thread there is various discussion on the feasibility of the recovery of the [allegedly] deleted data on the Captains flight simulator. The conclusion being that it was trivial is just deleted, but still possible [in certain cases] if overwritten.

In general, a determined enough organisation can recover overwritten digital data from hard-disks and tapes, especially if it is known what has been used to overwrite. Most computer data deletion standards mandate the data is overwritten with random data 5 or more times to be absolutely (spy) safe.

My question is, would the same apply for the CVR? If the duration is 2-3 hours, then the potentially interesting part was only overwritten twice - and perhaps overwritten with silence or a known base level of sound (aiding data recovery). Potentially even if only a few sounds or words recovered could be relevant (to define who was present on deck/a struggle).

Any thought on the feasibility of certain agencies recovering more than 2 hours from the CVR?

Of course, we need to find it first.

[iskyfly]

Would somebody be kind enough to recap ELT and CVR/FDR ULB ranges underwater and if working what type of equipment would be able detect them?


Thank you

[downwindabeam]

Probably asked and answered many many times, but searching in this thread is pointless almost.

In the 777, are the CVR and FDR circuit breakers in the cockpit? are they up above the overhead panel?

It almost seems to me that even if we do find the boxes, it will be meaningless. CVR being worth only 2 hours if we're lucky and it wasn't disabled and the FDR well.. again if it wasn't disabled.

[syseng68k]

James890:

Data remanence on CVR?

If they were still using magnetic tape, then there may be a chance to recover earlier recordings, much as overwritten hard drive data can sometimes be recovered if you have a right tools.

However, I would expect that modern cvr systems would record to flash or battery backed up memory. ie: digital rather than analog recording. Earlier contents would be overwritten in a continuous loop from the start of memory once end of memory is reached. There would be no way to recover data that has been overwritten...

[scr33d]

Earth's geoid is both non-symmetrical and well-mapped (GRACE and GOCE), Inmarsat may have done a relativistic gravitation Doppler analysis on the transmission to rule out the north arc. Will see if this is true as they give more details.

[Coagie]

Would somebody be kind enough to recap ELT and CVR/FDR ULB ranges underwater and if working what type of equipment would be able detect them?

An ELT won't work underwater. It's 406mhz radio waves won't travel through water. It is for use above the water or on land. The ULB is a 37.5khz buzzer, and it's sound waves, under good conditions, can travel about 2 miles. The sound is too high for a person to hear, so specialized equipment is used to convert it to human hearing range in order to detect it.

[Ian W]

Would somebody be kind enough to recap ELT and CVR/FDR ULB ranges underwater and if working what type of equipment would be able detect them?


Thank you

ELTs transmit on a satellite and some on aviation emergency frequencies and can be 'seen' by satellites almost anywhere on the Earth's surface. However, underwater their range is zero.

The CVR and DFDR underwater locator beacons have a range of ~2 - 3km underwater and are at a high frequency that almost all SONAR systems will not detect, their batteries are pretty wimpy too and may last 30 days 40 if extremely lucky. These design features seem to be at the behest of the airline beancounters. :(

To find the ULBs it is usually necessary to get within 2 km with a towed special purpose SONAR array, one is being transported from the US to the search area. However, the Indian Ocean in that area can be more than 3km deep..... Had the beancounters allowed a couple of hundred dollars more per aircraft then the ULBs could be lower frequency higher powered and a few hundred kilometers range and detectable by almost any ship with SONAR.

I would put the beancounters on deck on the SAR ships in the roaring 40's give them some binoculars and keep them at it till the wreckage was found. :E

[lynw]

I did try a reply before on this subject but my post seemed not to have been approved being my first one on the forum and all. So I will try again since the question of evidence recovery has resurfaced.:)

Please be gentle with me as I am not a pilot but I am a computer forensics examiner with over 10 years in the field. My original post was in response to a comment about examination of solid state drives that were discussed earlier as they are a whole new ball game in forensic examinations and not so straight forward to examine as traditional hard drives.

There are all kinds of issues with the SSD's that can affect their reliability - data can easily get corrupted if power goes midway through a write cycle. If these are to be used in future to preserve evidence of events, they are going to have to have some kind of power source of their own to ensure that data can be preserved and retrieved otherwise you are likely to recover dead drives. Even if you can resurrect them you will likely find the data corrupted, never a good start to a forensic investigation.

They also run the risk that the garbage process runs and wipes data even if you have the drive plugged into a write blocker. The only way to be absolutely certain that you wont lose data from one of these drives is to remove the drive controller and plug each flash memory chip into the write block hardware. Those interested in this can find more detail here:
Belkasoft - Leading Digital Evidence Extraction Software for Computer Forensic Investigations. (http://forensic.belkasoft.com/en/why-ssd-destroy-court-evidence)

As for the retrieval of data that has been overwritten using the previous write pattern on the disk, yes it is technically possible. But the reality of it is that there are very few organisations that will have the monetary, staff and time resources to put into retrieving that information - basically governments or research institutions. This capability isnt going to be available at your nearest PC World anytime soon :p

Whether data is retrievable and whether that is meaningful depends on a number of factors such as file system, the kind of overwriting that was done and even things like file size can determine whether the original data can be retrieved from the slack space. It ultimately comes down to how the data is recorded to the disk and whether you can determine what is data being recorded vs what is previously written data.

Its possible to retrieve fragments of old files which have been overwritten. This can be crucial in traditional law enforcement investigations because quite often it can show a file existed and also that it was deleted. A jpeg can be recovered from a very small part of the file remaining if you are lucky to the bytes that flag it as a jpeg - which can be crucial for a paedophile investigation to prove an image existed on the drive. However, audio and video data are far more complex to recover.

Even if you retrieve part of the file, you need other pieces of information to try and determine what part of the file you have. If you are lucky, and have the start, then its likely you will be able to find software that will play what part of the file you have. If you have lost the beginning of the file, thats a lot of time consuming work that needs to be done to try and get it back and recovered.

The simpler solution would be to put in drives that hold much more audio to avoid overwriting anything than to rely on being able to recover overwritten data.

[lomapaseo]

Floating debris from this aircraft in itself will give significant clues even without the recovery of the black boxes.

But, I'm not aware of any confirmed identified debris being recovered let's take a deep breath until then.

[ramble on]

Barit asked the question in post #2932

Can anyone with technical knowledge of the MAS 777 FMS answer the question definitively - did MH370 have an Emergency Descent Mode or not?

Newer business jets have it fitted.

[oldoberon]

IAN

With such a powerful "ping" they could already trawled the area and located the wreck

Like you idea for the bean counters make then feel the effects of their decisions, what is that cost compared to the original price of the plane , less than peanuts.

[ZAZ]

Would the 406 ELT work inside a faraday cage, with no ability for gps signal reception or comms with sarsat?


Same could be asked of a piece of coax terminated in a dummy/artitifical load.


We use shielded rooms to service sensitive equipment, while hundred KW transmitters run outside.
We use shielded rooms at primary airports to service avionics, when the door is shut with double screened rooms, a cage with a cage nothing gets in not even the nearby NDB.


When you shut the door it shuts out the world,


WIII SAYS
Faraday cages cannot block static or slowly varying magnetic fields, such as the Earth's magnetic field (http://en.wikipedia.org/wiki/Earth%27s_magnetic_field) (a compass (http://en.wikipedia.org/wiki/Compass) will still work inside). To a large degree, though, they shield the interior from external electromagnetic radiation (http://en.wikipedia.org/wiki/Electromagnetic_radiation) if the conductor is thick enough and any holes are significantly smaller than the wavelength (http://en.wikipedia.org/wiki/Wavelength) of the radiation.




That's why you can look through your microwave door and not get zapped.


However a slight amount fo escaping radiation from case or equipment direct l ine of sight to a satellite maybe only in order of microwatts. anything is possible...

I always tell the story of my aircraft where some rain got in and dripped into the external ELB switch, just enough to allow electricity to conduct through the switch
The eleb light was not on but I got called out of bed at 400am to go to the airport as using a hand held thay had traced it to my plane.
A satellite and subsequent overflying jets had narrowed it to my home base.
The elb was putting out microwatts

[TylerMonkey]

Previous graphic shows Oz with 1 search ship and no helos assigned.
Did it sail without a helo ? Maybe none available in Perth for the navy on short notice.

[eltonioni]

Beancounting is neither here nor there. ELT's are lifesaving equipment that transmit on internationally standardised frequencies to enable life saving, not underwater wreck recovery.

[Mesoman]

Too add to the ELT info. I don't know the specifics of the 777 ELT's (some others on here have more info on this). However, the following is general information that will apply to detection and localization of them.

Modern ELT's transmit a periodic 5 watt data burst on 460.25, which is received by low earth orbiting SAR satellites. They also transmit a lower power continuous "whoop-whoop" on the old ELT frequencies of 121.5 and 243, for direction finding during the final phase of localization.

The 5 watt ELT signal, even inside an aircraft like a 777, should be detectable at quite a range, even with the shielding effect of the aircraft hull. I suspect the SARSAT's would pick it up.

ELT's are frequently disabled by crashes (as mentioned by another poster earlier). The antenna can be severed, reducing the range to tens of meters, or the ELT can be destroyed. They are really designed for survivable crashes. They often have G-switches. The batteries are supposed to last a couple of days. I once found an older (121.5) ELT in an aircraft that had crashed and burned on landing - the heat from the fire had moved the ELT well off frequency, but it was still whooping.

Until 2009, COSPAS/SARSAT monitored 121.5 and 243.0. Now they only monitor 406.025. The latter frequency is sent with much higher power and better carrier stability, so the ELT location, derived from doppler as perceived by the satellite, is more accurate than with the older ELT's. ELT's on 463.0 are now monitored by both geosynchronous satellites and low earth orbit satellites (which do doppler processing, decode the digital beacon, and transmit the results to ground stations). Note that the geosynchronous satellites can provide near instantaneous notification of ELT activation, but may not give position.

Newer ELT's may also have GPS's and thus transmit GPS coordinate. They are also registered, so reception of a signal identifies the ELT. I once found one which was also shouting MAYDAY on 121.5 (recorded voice), making us think there was a pilot in distress, when in reality it was an accidentally triggered ELT in an parked aircraft. Grrr.


I suspect an ELT in the 777, built into the vertical stabilizer, might have much higher crash resistance than those in smaller aircraft, and the tail may stay intact.

[hamster3null]

Earth's geoid is both non-symmetrical and well-mapped (GRACE and GOCE), Inmarsat may have done a relativistic gravitation Doppler analysis on the transmission to rule out the north arc. Will see if this is true as they give more details.

This would be an extremely weak effect. Even the baseline for GR time dilation between Earth's surface and the satellite in a geosynchronous orbit is ~50 microseconds/day (5*10^-10), equivalent to frequency shift of just 1 Hz in the microwave band. Fluctuations in the geoid aren't going to be visible without sophisticated equipment.

[YYZjim]

Once the trigonometry of flight MH370 has been figured out, it is possible to do a few calculations to assess the effect of the airplane's speed on the frequency of the signals it used to communicate with the Inmarsat-3F1 satellite. I have assumed that MH370 flew for 6.83 hours along a great circle route from its last known position to a point over the debris field. I have also assumed that it flew at a constant airspeed of 850 kilometers per hour. It is possible to calculate the velocity of MH370 (both speed and direction) at every point along this route. It is then possible to divide this velocity into two components, one along the line-of-sight to the Inmarsat and the other at right angles to this line-of-sight. The following graph shows the component of MH370's velocity along the line-of-sight. At the start of its silent flight, MH370 was flying at a speed of 219.3 kph (kilometers per hour) directly towards the satellite and 821 kph directly perpendicular to the line-of-sight. Therafter, the airplane flew in a direction further and further away from the satellite, and the component of the velocity along the line-of-sight decreased. By the time the airplane reached the debris field, it was travelling radially away from the satellite at a speed of 500.5 kph and directly across the satellite's field-of-view at a speed of 687 kph.
http://www.mh370.ca/Radial_speed.gif
We have all heard the Doppler effect. It affects radio waves in pretty much the same way as it affects sound waves. The Doppler effect arises when there is relative motion between the source of the wave (a fire truck or MH370, for example) and the receiver (you or the satellite, respectively). The Doppler effect does not change the speed at which the waves travel. Instead, it changes the apparent frequency. The frequency of the wave transmitted by the source is not the same as the receiver heard by the receiver. When the source and receiver are travelling towards each other, the apparent frequency received is higher. The degree to which the apparent frequency is raised or lowered depends on the relationship between the speed with which the wave travels through the material between and source and receiver and the relative closing speed between the two. In the case at hand, the speed of the wave is the speed of light: 1,080,000,000 kph. The relative closing speed (above graph) ranges from 219.3 kph at the start of the silent flight to negative 500.5 kph (negative closing speed resulting in a lowering of the frequency) at the end. Expressed as a percentage of the speed of light, these two closing speeds are 219.3 / 1.08E9 = 0.00002% and -500.5 / 1.08E9 = -0.00005%.

These are very small shifts in frequency. Big passenger airplanes use at least four frequency ranges, called "bands", in their communications. When the pilots talk to ground control, they use frequencies a little bit above 100MHz, just above your FM radio. The "Primary Channel Worldwide" for the ACARS reporting system is 131.55MHz. Much has been heard in the aftermath of MH370 about the use of satellites to relay the ACARS information, but the bulk of ACARS messages do not pass through satellites. When airplanes fly over land, the ACARS communications go over a land-based, cheaper network. The transponders about which we have heard so much are sent at frequencies near 1030MHz. When airplanes are far out over the sea, and communicate their ACARS data through satellites, they use even higher frequencies. The Inmarsat-3F1 satellite transmits at 1630MHz and receives at 1530MHz. One assumes that the Inmarsat study into the Doppler effect used data exchanged at these higher frequencies. Since the airplane's speed is such a small fraction of the speed of light, the percentage shift in frequency will be almost proportional to the relative speed percentages described above. The following graph shows the frequency shift (in Hz) which would be experienced by a continuous radio wave transmitted at 1600MHz by MH370 to the satellite during its silent flight.
http://www.mh370.ca/Frequency_shift.gif
These frequency shifts range from an increase of about 325Hz to a decrease of about 750Hz. I will say this: the Inmarsat people must be very good engineers to detect such small changes in a 1600MHz carrier, particularly when their radio equipment was probably designed to overcome and ignore such noise.

[GlueBall]

There have been numerous idiotic comments in this thread blaming the crew, directly or indirectly. Since most of the so-called 'facts' implicating the crew seem to have faded-away,

But it's hard to conceptualize any non experienced B777 pilot disabling TXP & ACARS, turning, descending, and steering the airplane in an evasive flight profile towards the middle of a remote ocean without attempting to communicate if there was a mechanical fault or hijacker interference.

[nupogodi]

As for the retrieval of data that has been overwritten using the previous write pattern on the disk, yes it is technically possible.

Hello,

As an forensics professional, you are aware that magnetic force microscopy has never been used to recover data off once-overwritten magnetic media. I assume you are also aware of the 2006 NIST Special Publication which stated that using magnetic force microscopy to recover data from magnetic media of any considerable density is impossible. Since you would know all this, I wonder why you would make such a statement.

It is also irrelevant since the CVR/FDR would not be recording to magnetic tape on the accident aircraft.

[Hogger60]

Yes, and if we do, there may be no data on it.
Someone might have pulled the C/B to shut it downNo, once again, there is no circuit breaker for the CVR nor for the FDR in the cockpit on the 777.

And no, there is Emergency Descent mode in the FMS.

[PlatinumFlyer]

Chris McLoughlin of Inmarsat was just on The Kelly File. When she pressed him, he stated that the plane took the southern route. This was based on their comparisons of pings from other Malaysian aircraft that took the northern route.

http://foxnewsinsider.com/2014/03/20/inmarsat-flight-370s-location

[Roadster280]

Could the membership explain something to me please?

As I understand it, the a/c had reached 35K or so after departure, and then abruptly turned and descended to 12K over Malaysia on its way south. It eventually appears to have crashed at, or just beyond, the predicted fuel exhaustion radius.

Would that fuel exhaustion radius be the range at 12K, or for a B777 at a "normal" cruise altitude (i.e. 30-40K)? I imagine the radius at 12K is considerably shorter.

If it's the higher altitude, then the question in my mind is how/why did it regain altitude? If it could only be by commanded intervention, then I'm at a loss as to why it continued in a straight line.

Conversely, if it had all gone wrong an hour or so after departure, and they had headed home or to an alternate airfield, at 12K, but just not made it, why would the aircraft ascend (if it did) to reach the range that it appears to have.

Or is the range to where the search is currently centered "reasonable" at 12K?

[CommanderCYYZ]

It's actually much easier to recover data from over-written digital media. FBI software can recover data from digital media that has been over-written multiple times, or reformatted repeatedly.

[atr-drivr]

If in fact the airplane did get down to 12K over Malyasia, I find it disturbing that NO phone data was found. Not one passengers phone was left on or if a rapid decent no one tried to call home or anyone? Has there been any attempt to pull passengers phone records for the time frame??
As a commuter I see all the time peoples phones on, and not in airplane mode....

[G0ULI]

Roadster280

There is considerable doubt about the reported height of the aircraft as determined by radar. The INMARSAT data indicates that the aircraft flew at constant altitude and speed in order to reach the area that is now being searched for debris.

Radar tracking of primary returns can be very inaccurate unless a target is being deliberately targetted and tracked. The track and height of MH370 seems to have been derived from sweep recordings of the radar examined after the event. The aircraft was initially flying along civilian airways and not towards any military installations when it turned off its planned flight path. Since the aircraft was assumed to be a civil flight and did not represent a threat, it was not tracked. The estimates of the height and possible altitude changes were all calculated (or estimated) after it was announced that the aircraft had disappeared.

Clearly the military will not want to reveal the capabilities or shortcomings of their radar systems or alert status, so the radar data and height changes reported should be regarded as being possibly inaccurate or not having occured at all.

[Roadster280]

Ok, that makes sense. If the descent to 12K and then climb to a normal cruise altitude potentially didn't take place, then that answers my question. Thanks!

[Capn Bloggs]

The AF447 did not take two years to be found,the black boxes took two years.
Pedanticism. The only things "found" straight away were small floating bits and the fin. The main wreckage, which included the main tail and fuselage sections and the recorders at the bottom of the ocean, was not found until almost 2 years after the prang.

[imaynotbeperfect]

A few comments on this thread about the lack of mobile phone use

4 years ago I flew from LHR via BKK to SYD. On departure I put the phone in the overhead bin. 23hrs later on arriving at SYD I went to turn it on only to find I'd not actually turned it off. The only messages were welcoming me to Bangkok and Sydney which surprised me given that we'd tracked over most of Europe.

[goeasy]

I understand the Inmarsat investigation has confirmed there was no descent below 30000ft.

It is exceptionally unlikely they followed the initial descent and then re climbed back to 30k.

They will find this aircraft. They have to. The insurance industry will finance a lot of it to try and ensure there isn't a repeat. Just like AF447.

[atr-drivr]

imaynotbeperfect,
I see that of course but since the supposed lower altitude was significantly lower than your cruise alt thence my observations...

[Runcible]

Prevailing Southern Ocean current systems south of the present MH370 search area would appear to favour any MH370 flotsam eventually turning up along the shores of Heard and McDonald Islands - some 1400 kms further to the SSW.

I wonder how often ships visit these seal-populated Australian protectorates? (and whether they could/would ever be tasked to scour their shorelines?).

As far as Australian government departments with responsibilities in these areas would be aware, they'd just not know about any such visits by sealers or sea-bird harvesters. I doubt that any Jap whalers or such-like would ever visit these Antarctic-proximate islands except to ravage the seal-population - and wouldn't bother applying for visas to do so.

[G0ULI]

CommanderCYYZ
Digital data can be recovered from large capacity USB sticks and the like because new data is written to 'fresh' areas of memory. When a file is deleted, only the file name is deleted and the memory locations used flagged as available to be re used once all the other free space is used up. Essentially the same technique has been used in floppy disks and magnetic hard drives. So data can be deleted but it is not overwritten until there is nowhere else to put new information that needs to be recorded. Quick formatting a flash drive, doesn't delete the data on the drive, it just resets it so that all memory positions are shown as being available to be overwritten. A full low level format of a flash drive will irrevokably delete all data.

With smaller sized memory devices that are constantly being overwritten with new data, it is not possible to recover anything more than a few memory blocks of data that has been deleted to make way for overwritting new data.

So with multi-gigabyte and terabyte drives used in typical laptop and desktop computers, there is a very good chance of retrieving huge quantities of deleted data using forensic software. This is because the capcity of the drives means that the deleted data is never overwritten because the drive never fills right up. The memory chips used in the flight data recorder are too limited in capacity for any useful additional data to be recovered apart from the latest recording.

Old style floppy disks which were swapped between computers had relatively wide tracks of data and poor tolerances with regard to the accurate positioning of the read write heads. It was possible to recover previously written files in some circumstances, even though they had been overwritten by new data. Modern hard disks operate to such fine tolerances, that once data is overwritten, there is virtually no chance of successfully recovering the original data. A magnetic hard drive that has been reformatted may retain a faint magnetic trace of data that was written to the drive provided that it has not been overwritten by new data.

The labouriousness and costs associated with forensic data recovery cannot be overstated. It takes ages, costs an absolute fortune and frequently all you end up with is fragments of files that are unsuitable for evidential purposes, but can assist a stalled investigation. I once spent six weeks recovering the contents of eight floppy disks. I would hate to have to try to rebuild more modern memory devices.

[rampstriker]

AF447 crashed in an area where the sea floor was pretty mountainous, with canyons and ridges everywhere (I found the great graphic below here (http://www.ahrtp.com/RSS-JSfeeds/AF_447_weather_pitot_tail_hypercomplexity-2.html)).
http://i.imgur.com/JS9dDWw.jpg?1

The sea floor where they think MH370 crashed is basically one big abyssal plain: featureless and flat. I suspect this might make wreckage more apparent in sonar scans, compared to AF447.

[India Four Two]

4 years ago I flew from LHR via BKK to SYD.

maynotbe perfect,

I had the opposite experience. LAX to BKK. Welcoming messages from mobile companies in Alaska, Russia, China and Taiwan.

This happens due to the aircraft being in a high-angle antenna sidelobe long enough to make a connection. I expect you might be able to send an SMS during one of these brief connections, but I doubt you could make a voice call.

[Earl]

http://news.yahoo.com/pilots-tried-save-mh370-193000845--politics.html
This seems more reasonable than any other explanation.
Look at what happened, we have been taught this in the sim for many years, descend, turn off the tract, land at nearest suitable airport.
Seems they tried to do this.
Even Fox News Bill Reilly slams the pilots.
I hope when the news agency are proven wrong they have the respect to state it.

[slats11]

These frequency shifts range from an increase of about 325Hz to a decrease of about 750Hz. I will say this: the Inmarsat people must be very good engineers to detect such small changes in a 1600MHz carrier, particularly when their radio equipment was probably designed to overcome and ignore such noise.

The official explanation does not have to be strictly true. It probably only has to be plausible.

I hope and believe there is indeed independent evidence used to refine the Inmarsat data. If so then I believe we will eventually find the aircraft.

It would seem strange if 7 or 8 pings were heard by a satellite in ego orbit, and not one was heard by other satellites designed specifically to pick up faint signals. Particularly given the pings were coming from a fairly quiet location (mid-ocean), but from a general area (mid east and Pakistan) covered by plenty of satellites.

Would it be possible that people were even looking for the aircraft towards the end of its flight when they knew it was missing?

[Bobman84]

Pedanticism. The only things "found" straight away were small floating bits and the fin.

You forget about the bodies they found too initially?

[Shadoko]

About the Doppler effect: it is because the sat moves that the distinction north/south had been made. The sat speed varies something between 200 and 300 kph along its tinny orbit. See these excellent posts:
http://www.pprune.org/rumours-news/535538-malaysian-airlines-mh370-contact-lost-396.html#post8398811
and
http://www.pprune.org/rumours-news/535538-malaysian-airlines-mh370-contact-lost-398.html#post8399042

About the cellphones "not pinging": the question was in air (!) many posts ago and somebody told that a search about those of the crew had been made and nothing had been found. Unfortunatly, I think these ones have the most chance to be off and I doubt the ones of the pax were also searched: anything credible about this?

Is there anything in Inmarsat and/or AAIB which implies the a/c was west of Malacca Strait at one time? Or we will be said later MH370 flew straight above Indonesia?

[Blake777]

Re mobile phones

THE Malaysian Communications and Multimedia Commission (MCMC) attempted to triangulate the location of Malaysia Airlines flight MH370 using phone numbers of passengers on board but to no avail.
The exercise was carried out after it was confirmed that the Boeing 777 jetliner had gone missing.
This was done following claims that family members of passengers from China had established cell phone communication with them.
Sources told the New Straits Times that Captain Zaharie Ahmad Shah's cell phone was last used on Friday night, just before take off.
MCMC also zeroed in on three other cell phones belonging to MH370's passengers, namely the wife and two daughters of former Celcom Axiata Bhd chief executive officer Datuk Mohamed Yunus Ramli Abbas.
Efforts to locate signals from the cell phones of Biby Nazli Mohd Hassim, Dina Mohamed Yunus Ramli and Maria Mohamed Yunus Ramli were all unsuccessful.
Bukit Aman's forensics team had also carried out a similar exercise in collaboration with foreign counterparts to establish when the last contact was made by those on the aircraft.


Read more: Triangulation using cell phones fails - General - New Straits Times Triangulation using cell phones fails - General - New Straits Times (http://www.nst.com.my/nation/general/triangulation-using-cell-phones-fails-1.520250#ixzz2wwpZ42NM)

[Sheep Guts]

Well if INMARSAT are right, and lets hope so. We need a lot of luck to find this aircraft now, in that Southern Ocean. Because there is a lot of sea trash, and horrible weather which is only going to get worse as we approach the southern winter season. Can the underwriters see what sort of search bill its going to be?
Will there also be now a Preliminary Accident Report issued by the Malaysian Accident Investigation Board or Team?

[500N]

My guess is if they can narrow the location down a bit,
the towed array from the US Navy will hopefully find it.

They only need to find a few bits of wreckage on the sea floor
and that will set them on the right course.

The problem is of course finding those first bits !

[sardak]

Mesoman and others -
The 406 ELTs currently transmit on one of several different frequencies: 406.025, .028, .037 and .040, depending on when they were built. There are additional freqs reserved for future expansion of the system. A reason for this is a lot of science involving packet theory and collisions between the data bursts from the beacons.

The Doppler frequency is determined by the satellite and position is calculated on the ground at LEOLUTs (LEOSAR local user terminals). This Cospas-Sarsat document goes into much of the gory details: http://www.cospas-sarsat.org/images/stories/SystemDocs/Current/CS_T002_OCT_2012.pdf LUT locations are shown here: LEOSAR Satellite Coverage (http://www.cospas-sarsat.org/en/system/detailed-system-description/leosar-satellite-visibility-areas)

The GEOSAR system consist of geostationary satellites that detect the beacons and GEOLUTs. No Doppler location is determined from them, they provide alerting and data burst relay including position for beacons with a global navigation system.

In development right now is the MEOSAR system, using receivers on GPS, Glonass and Galileo nav satellites. Among the features and advantages of this system is return-link (two-way) capability between the rescue coordination centers and the beacons. Intial operational capability is scheduled for 2018. References for all of these systems can be found on the Cospas-Sarsat website: International Cospas-Sarsat Programme (http://www.cospas-sarsat.org)

As for beacons transmitting from inside a plane being detected by the satellites, maybe, maybe not. From deep underwater, no. From a crash on land, maybe, maybe not. Lots of factors involved. The most recent published study on the effectiveness of beacons in crashes was published last year by the Australian Transport Safety Bureau. http://www.atsb.gov.au/media/4126629/ar-2012-128_final.pdf

For more on ELTs, including a reference for the g-force activation criteria, deployable beacons and more, see this thread spun off from here: http://www.pprune.org/tech-log/535756-elt-doubts.html#post8376340

Final bit of info, the last week of January of this year was a meeting of the ICAO Asia/Pacific Regional Search and Rescue Task Force in Singapore. 15 of the 44 countries in the region sent representatives, as did ICAO, IMO, IATA and Cospas-Sarsat. Among the countries not in attendance were Malaysia, Vietnam and China. Counted in those which were are Australia, India, Thailand and the US.

Agenda items included (4) Asia/Pacific and inter-regional SAR planning, coordination and cooperation and (5) Asia/Pacific Regional SAR Plan. The minutes note: It was recognized that many States have difficulties in enacting SAR agreements with their neighbouring States.

[Shadoko]

From FR24, when "something happened", the heading was 25° or 18°. If (If) the "left turn and descent" was applied (decompression) and crew choose to return to KL with a reverse heading (205 or 198) and then things gone very bad for everybody in the a/c, could she fly to were she finished because of magnetic specificity of the south west of Sumatra?

[vapilot2004]

In the 777, are the CVR and FDR circuit breakers in the cockpit? are they up above the overhead panel?


No, they are located below in the MEC otherwise known as the EE bay.

[Jilted]

From FR24, when "something happened", the heading was 25° or 18°.Actually the last two ADS-B returns on FR24 show a heading of 40°.

[Blake777]

Have a look at Capt Kremin's post on this, currently sitting at #7541.

[bud leon]

Good piece about the awful performance of the media (which has clearly influenced many of the less thoughtful posters on this thread) here:

It's about the media, not the plane - The Drum (Australian Broadcasting Corporation) (http://www.abc.net.au/news/2014-03-24/mcdonell-media-frenzy-descends-on-mh370-mystery/5340242)

[Centaurus]

If the cb was pulled for the data voice recorders i am confident the perpetrator would have made a blunder in his grand plan as the initial cockpit struggle would be preserved on the cvr

Your theory that a cockpit struggle would have been evident assumes both pilots were in the cockpit at the same time. In the case of the Silk Air MIA 185 B737 suspected suicide crash, the circuit breakers for the CVR and FDR were found to have been actuated by physical means not an electrical fault. it was thought the most plausible scenario was the captain conned the co-pilot to leaving the cockpit on the pretext of sending him to the cabin to investigate an event (eg leaking door seal). It was speculated that once the co-pilot had left the cockpit the captain locked the door, and pulled both FDR circuit breakers (that action activates the Master Caution light).

It was considered very doubtful the captain pulled the dual circuit breakers for the FDR while the co-pilot was still in the cockpit, as the illumination of the Master Caution Light would have alerted the co-pilot something dodgy was being planned. There was evidence the captain had already previously pulled the CVR circuit breaker situated behind his own seat and out of the forward sight of the co-pilot. Easy done as he had practiced that before on the ground on a previous flight.

Pulling the CVR circuit breaker (B737) does not activate the Master Caution and the co-pilot would have been unaware the CVR circuit breaker had been pulled by the captain who had himself left the cockpit a few minutes earlier on a visit down the back.

[martynemh]

What was the genuine 'Last Known Position? Was it really 200nm WNW of Penang VOR (or variants of this), or was it 'close to the Malaysia/Vietnam FIR boundary?

And for Capt Kremin (#7541), if your coloured lines were drawn from the latter, how does that alter the 'final' assumed position?

If the crew made a left turn back from the FIR boundary towards 'home', be it PEN or KUL on HDG (I guess around 190 deg M or so), and were then overcome by events, where would that autopilot have taken them?

[500N]

Bud

Interesting article.

I was looking at some photos of the media at RAAF Base Pearce the other day, all quietly lined up and waiting patiently on the edge of the grass next to the runway with one military person watching over them. Same out the front of the base. Amazing what happens to the media when the law is laid down to them at the start :rolleyes:

[Blake777]

I haven't seen much true wavering from the position that 200WNW of Penang was the last trace of MH370. Someone here posted a link to a Chinese paper which reproduced the military primary radar data as shown to Chinese relatives. I took a copy but no longer have the actual link.

It all depends if you believe there is sufficient evidence that the aircraft tracked west of the Malacca Straits, or whether you want to believe it could have been a ghost plane after a failed attempt to head to a nearby airport or perhaps KL.. Either way, I think Capt Kremin's point stands that a ghost plane scenario will have been determined to have been either true or false depending on the location of the final six pings. As we don't have that information, we can only surmise that investigators have come to the position that the diversion was a deliberate act because they do have that information, which would probably show that a direct heading south in a straight line had to have had human input and could not be simply a ghost plane flying itself after a catastrophe.

Time will eventually tell, and even though the search is daunting, I feel we will get some answers, even if not all of them. We must go wherever the evidence leads.

[Bobman84]

All 'speculation' until MH370 debris found (http://news.ninemsn.com.au/world/2014/03/25/00/36/malaysian-pm-to-brief-press-on-plane)

Defence Minister David Johnston says until debris is recovered and positively identified as being from Malaysia Airlines flight MH370, any information about the search for the missing plane is speculation.

Malaysian Prime Minister Najib Razak told a press conference in Kuala Lumpur late on Monday that based on new analysis by the UK Air Accidents Investigation Branch and tracking firm Inmarsat, the plane flew along the southern corridor and crashed into the ocean west of Western Australia.

But Senator Johnston said while the British data is all the authorities have to go on, he stressed no debris had yet been recovered from the massive search area in the Indian Ocean.

"The turning point for us, I think, will be when we pull some piece of debris from the surface of the ocean and positively identify it as being part of the aircraft," he told reporters at the RAAF Pearce air base north of Perth on Tuesday.

"This is a mystery and until we recover and positively identify a piece of debris, everything is virtually speculation."

He said the search continued to be "fairly urgent" given there's only some 13 days of life left on the beacon battery that would pinpoint the location of the black box.

This.

[OleOle]

Doppler shift has not to be regarded in relation to the carrier frequency (1,6 Ghz) but in relation to the baseband bandwith, i.e the part of the signal that carries the payload.

5kHz is a number I found for channel spacing in Inmarsat-C. So with a doppler shift in the range of 1khz, speed accuracy should be pretty good.

[DaveReidUK]

Beancounting is neither here nor there. ELT's are lifesaving equipment that transmit on internationally standardised frequencies to enable life saving, not underwater wreck recovery.

I believe the "beancounter" comment was made in respect of the ULBs (Underwater Locator Beacons) attached to the FDR and CVR.

Given that those are beacons to help in locating said objects underwater (the clue's in the name), the comment is entirely relevant.

[gaunty]

Bobman84

yup waiting for the weather to clear. Its pretty ordinary weather when the Australian Navy withdraws from the area to calmer waters until it clears.

Its pretty clear from the reports and my understanding of the area, the more assets you use and the more you look in these parts the more you will find, it's a really wild part of the ocean with winds and currents that run unrestricted by any land around the world.
it will be carrying years of debris that has fallen off ships or swept off beaches

Hardly anybody ever goes down that way for fun or commerce, except the crazy round the world yachting crazies and they have a horizon of less than a couple of miles. Usually the first they know there is a large piece of debris seatainer or such like is when they hit it. :sad:

IMHO they are better off concentrating searching for a pinger.

And I hope they haven't given up on the Northern end.

[SOPS]

I'm pretty sure they have given up on the Northern end, Gaunty.

[Sheep Guts]

The radar plots after the turn back are patchy. What is the latest info they have on this with all the combined Radar. There have been many versions. What was their first heading or track immediately after turn back?

[500N]

"Its pretty ordinary weather when the Australian Navy withdraws from the area to calmer waters until it clears."


The Captain has seen action all around the world, she knows what she is doing.

[mm43]

The problem is of course finding those first bits !

The Towed Pinger Locators (TPL's) are to detect the Underwater Locator Beacons (ULB's) - one attached to the DFDR, and one attached to the CVR. They have a guaranteed battery life of 30 days, but the manufacturer will probably ensure that is extended to about 40 days. In the AF447 case, neither worked, and one was never found.

The ROV option is only useful when you have found something worth taking a look at. Initially, and if the ULB's are not located, a dedicated underwater search plan needs to be drawn up based on the best information available. In the MH370 case, the area selected to search will probably not be less than that which was searched using Autonomous Underwater Vehicles (AUV's) to find AF447, in which case this whole operation will take not weeks, but many months if not a year or more.

Why? The backtracking of surface floating debris is not a precise science, and the "butterfly effect" created by spurious vortexes that spin stuff off and then repeat the process, tends to confuse the issue.

Don't hold your breath.:sad:

[Howard Hughes]

Yes that may be one obvious conclusion but hopefully the NTSB / AAIB / Malaysian / French investigators retain open minds; for example that all comms and pilots could have been wiped out by an event as yet unknown and it flew itself to its final resting point.
That's what I'm sticking with at the moment! :ok:

[sky9]

I see that Inmarsat have used a speed of 450 kts for their calculation. Assuming that a 777 operates at 0.84 or there abouts that equates to a TAS closer to 500kts.

How would that affect the arcs that they have published and how far down those arcs the aircraft might have flown.

[lapp]

@syseng68k
It's actually much easier to recover data from over-written digital media. FBI software can recover data from digital media that has been over-written multiple times, or reformatted repeatedly.

Absolutely false. As mentioned before, it is simply impossible to recover any physically overwritten digital information.

[Speed of Sound]

How would that affect the arcs that they have published and how far down those arcs the aircraft might have flown.

The aircraft did not fly down the arc. The arc represents the possible range of locations when the final 'ping' was received.

[Blake777]

I'm going to lift a couple of sections out of Capt Kremin's previous post here because it's evident that investigators will already know, based on the exact location of the previous six pings, whether the excursion south was likely to have been accidental or deliberate.


In the case of the "Ghost plane" scenario the aircraft, after it turned WNW would have been either tracking to a programmed FMC waypoint or it would have been in a lateral AP mode referenced on magnetic north, HDG or TRK, it does not really matter. If tracking to the FMC waypoint, once it reached it, it would have reverted to HDG.

For the aircraft to track direct to the area of the last known ping and the current search area, there are only two ways to do it. One is a programmed FMC waypoint and the other is someone flying the aircraft via the HDG or TRK button and taking into account the 30-35 degree change in magnetic variation encountered along the route.


His point is that the track revealed by the pings will show either a direct straight path, or one which curves due to reversionary AP modes and changes in magnetic variation. His post is complete with charts etc and is currently number 7541. Well worth reading.

A straight path would indicate a deliberate diversion. Since investigators are labelling the route deviation a deliberate diversion, it would be reasonable on this basis to rule out a ghost plane - and it doesn't really matter from which exact point the diversion south commenced, though his reasoning is based on the point 200nm WNW of Penang.

[fireflybob]

Has anyone asked the question as to whether the Malaysians had been warned about potential terrorist activity on this flight?

Journos - perhaps a good question to ask at the next news conference.

[GlueBall]

...hopefully the NTSB / AAIB / Malaysian / French investigators retain open minds; for example that all comms and pilots could have been wiped out by an event as yet unknown and it flew itself to its final resting point.

...but magically only the autopilot kept working?

[mickk]

The worst type of terrorism would be to make an aeroplane vanish, then do it again.

Pilot suicide is an easy way out for the Authorities.

Slow decompression ala Helios has to be a strong possibility perhaps with one last confused pilot input or passenger input befiore she went down. Smouldering fire may have the same effect and take out systems also.

The turning off of systems has not been adequately explained, black box may do so.

[OleOle]

Blake777

A straight path would indicate a deliberate diversion. Since investigators are labelling the route deviation a deliberate diversion, it would be reasonable on this basis to rule out a ghost plane

I totally agree with the conclusion, that once established whether the flight path was a path of constant magnetic heading or was a great circle, then it can be inferred if it was deliberate action.

Captain Kremin visualized that very well.

I don't agree that we can conjecture yet, that the investigators have already established whether the flight path was constant heading or great circle.

I was always wondering why only the last section of the tracks in the AMSA maps are depicted. I think those paths are only symbolic because a path of constant heading would appear to come out of direction of Diego Garcia. NTSB doesn't want to complicate the matter to the public by explaining magnetic deviation and rhumb lines and that's the reason for only displaying symbolic tracks.

[Intruder]

Absolutely false. As mentioned before, it is simply impossible to recover any physically overwritten digital information.
Not so absolute...

While solid state media cannot retain overwritten information, hard disk drives CAN retain forensically retrievable information. That is why the US Dept of Defense has had long-standing protocols for multiple repeated overwrites of HDDs to completely erase classified information.

[OPENDOOR]

I am having some serious trouble believing that it is beyond the ability of the worlds aircraft manufacturer's to retrofit several EPIRB's to the outside of the fuselage of modern airliners.

Google; SMARTFIND G5 GPS (AUTO FLOAT FREE) they cost about £500

MH370 would have been located in minutes and the wreckage found in hours.

With the relatively simple addition of a solid state memory unit storing the last six hours of information fed to the FDR/CVR would result in EVERYTHING that had happened being known within hours not days or weeks or years or never....

For God's sake, I could build one:ugh:

[sky9]

The aircraft did not fly down the arc. The arc represents the possible range of locations when the final 'ping' was received.
I'm aware of that but the search area is based on the arcs and the area of search has apparently been based on 450kts if Inmarsat are to be believed.

[Golf-Mike-Mike]

...hopefully the NTSB / AAIB / Malaysian / French investigators retain open minds; for example that all comms and pilots could have been wiped out by an event as yet unknown and it flew itself to its final resting point.
...but magically only the autopilot kept working?

Well it was suggested way back on this thread by those who know about the busses for the comms systems (VHF, xpdr, ACARS,...), that they're separate to those for the autopilot? But your scepticism may well be justified.

[A33Zab]

Quote:
Yes that may be one obvious conclusion but hopefully the NTSB / AAIB / Malaysian / French investigators retain open minds; for example that all comms and pilots could have been wiped out by an event as yet unknown and it flew itself to its final resting point.

That's what I'm sticking with at the moment! :ok:


Dual AIMS cabinet fail?

http://i474.photobucket.com/albums/rr101/Zab999/AIMSRelated_zpscb0f164b.jpg

[oldoberon]

JAMES07

Plus no activation of the portable ELT by the cabin crew.

Assume you mean active them and hold by windows each side of the aircraft hoping it would be picked up by satellite or other aircraft.

A cabin crew member posted that they were never taught that might work, but he would mention it to their training staff. That's just one airline wonder what the others do?

[memories of px]

well maybe he couldnt get any response from vhf 1 so tried box 2, no joy there so try box 3 which is set to DATA, one quick press of the transfer button and its on vhf, but no joy either, doesnt return the setting to data. so no acars

[ionagh]

Google; SMARTFIND G5 GPS (AUTO FLOAT FREE) they cost about £500

MH370 would have been located in minutes and the wreckage found in hours.

You can forget the idea of one of these being of any use. The impact energy of a vessel capsizing is just a little bit less than a 500mph impact with the sea.
The maximum test applied to marine EPIRBs is something like a 20m drop into water or a 1m drop onto a wooden floor.

Fitting marine EPIRBs would simply add to the debris field, that is all.

[Mr.Buzzy]

It's time for flight decks to be fitted with a portable oxygen cylinder and mask.

Oxygen cylinders have ruptured in the past and punctured the fuselage.

Imagine the one and only oxygen cylinder for both pilots ruptured and punctured the fuselage.

Imagine cruising at high altitude, explosive decompression, (possibly taking out some avionics) grabbing for your mask and seeing the webbing not inflate.

It's a nasty scenario and one that would see cabin occupants being awake longer than flight deck crew.

[AviatorDave]

Just my two centsworth.. but if I was planning a suicide run I would certainly choose to start my deviation from flight-plan route at the point of ATC frequency changeover... you've said 'bye to the previous centre and the next one will probably wait an age before alarm bells ring... As I said, just MHO.. but seemingly what happened here.

TP

The catastrophic event right at the ATC handover point of time, the following weird track of the aircraft (with the FMC route altered beforehand), the altitude changes (up, down, up again) and the final course set to one of the most remote areas of this world where recovery of bodies, wreckage and CVR/FDR are nearly impossible.

I don't know. All of this could have a trivial and hardly sensational explanation that in hindsight will perfectly fit the facts we know at the moment, but I have a strange feeling about it. Something just doesn't look right.

[ionagh]

Ah yes, one of the "it-can't-be-done" brigade.

Not what I said. A marine EPIRB would not be good enough.

Now if you want to design an aero EPIRB with full impact encapsulation and ED-12 certified software then that is another matter and another price.

[multycpl]

I think that this now shows that the idea of just the onboard black boxes must change...Airfrance and now this crash must push for an external radio recording device to be retro fitted to all transport planes a.s.a.p.

[Squawk_ident]

The Minister of Transport just said that a detailed Press release will be given just after the PC, with some detailed data from AAIB.

[mixture]

Could this secondary flight plan have been activated easily with a few keystrokes?


The PPRuNe search function suggests "secondary flight plan" has been discussed 663 times already on this very thread.... :cool:

[EcamSurprise]

Could a black box not be fitted with a GPS tracker?

[slats11]

I think that this now shows that the idea of just the onboard black boxes must change...Airfrance and now this crash must push for an external radio recording device to be retro fitted to all transport planes a.s.a.p.

Agreed.

When recorders were developed, all you could do was record the data onto a local device, make the device as indestructible as possible, and hope it could be found in the event of a crash.

In 2014, that seems almost quaint.

It's like backing up important files on your laptop to a separate folder on the same laptop. Pretty much useless if your laptop gets stolen.

I do understand pilots concerns about privacy. But the reality is that most people do have to be a bit discreet about conversations they have in their workplace.

Perhaps the solution is to have the data stored at a central location (e.g. NTSB), only to be accessed as part of a formal investigation, and not routinely available to company management.

[Squawk_ident]

I'm looking at various sites to have an idea about maritime current in the region 43.976S/90.96E (Chinese debris picture: -43° 58' 34.0 90° 57' 37.0 ) to try estimating the approximative position of the aircraft at impact on the sea.
The average current is 0.2m/s in this area and with a South Eastern direction. It gives roughly 0.72 km/h,that is a 17.3 km per 24 hours. The aircraft disappeared in the ocean on the 8th of March, 8 days before the picture, it would make a SE 140km drift.
It can be applied the same drift for the French debris although we only that it is 550 km in the North.
Of course this a pure speculation and we still do not know yet if these debris are from Flight 370.
Unfortunately the weather is not good at this time and searches are halted.


http://i61.tinypic.com/nzq7ti.jpg
Sources : oceanmotion.org and oceanweather.com
It is interesting also to look at Skyvector and add the "barbs" to the Weather layer.

[oldoberon]

before holding up the portable elt's to the windows, lol, you better remember
to all stand around pissing on it cause its probably a rescu406 which battery is activated by salt water.

isn't that for the two flotation devices, elt are meant for crash on ground use so no need to take a leak

[ionagh]

I think the idea of EPIRBs is not the best way forward. I would think more about using the satellite broadband link. Audio feed parallel with a CVR channel, 48 kb codec (G722 or similar would give enough audio bandwidth to ID warning tones) add a 2kb slow data channel for an integrated GPS data. Add error correction and you could fit 2 into the minimum broadband link.
Activation could be for example an aircraft loses ADS-B, VHF comms, departs flight plan, departs cleared altitude etc then ATC could poll the aircraft and switch on the CVR link.
Automatic battery back up incase of power failure.

The issue will be with how those in the cockpit feel about possible remote monitoring of anything they say?

[A69]

Information provided to mh370 investigation by uk air accidents investigation branch (aaib)


25/03/14

on 13 march we received information from uk satellite company inmarsat indicating that routine automatic communications between one of its satellites and the aircraft could be used to determine several possible flight paths.

Inmarsat uk has continued to refine this analysis and yesterday the aaib presented its most recent findings, which indicate that the aircraft flew along the southern corridor.

As you have heard, an aircraft is able to communicate with ground stations via satellite.

If the ground station has not heard from an aircraft for an hour it will transmit a 'log on / log off' message, sometimes referred to as a ‘ping’, using the aircraft’s unique identifier. If the aircraft receives its unique identifier it returns a short message indicating that it is still logged on. This process has been described as a “handshake” and takes place automatically.

From the ground station log it was established that after acars stopped sending messages, 6 complete handshakes took place.

The position of the satellite is known, and the time that it takes the signal to be sent and received, via the satellite, to the ground station can be used to establish the range of the aircraft from the satellite. This information was used to generate arcs of possible positions from which the northern and southern corridors were established.

Refined analysis from inmarsat
in recent days inmarsat developed a second innovative technique which considers the velocity of the aircraft relative to the satellite. Depending on this relative movement, the frequency received and transmitted will differ from its normal value, in much the same way that the sound of a passing car changes as it approaches and passes by. This is called the doppler effect. The inmarsat technique analyses the difference between the frequency that the ground station expects to receive and that actually measured. This difference is the result of the doppler effect and is known as the burst frequency offset.

The burst frequency offset changes depending on the location of the aircraft on an arc of possible positions, its direction of travel, and its speed. In order to establish confidence in its theory, inmarsat checked its predictions using information obtained from six other b777 aircraft flying on the same day in various directions. There was good agreement.

While on the ground at kuala lumpur airport, and during the early stage of the flight, mh370 transmitted several messages. At this stage the location of the aircraft and the satellite were known, so it was possible to calculate system characteristics for the aircraft, satellite, and ground station.

During the flight the ground station logged the transmitted and received pulse frequencies at each handshake. Knowing the system characteristics and position of the satellite it was possible, considering aircraft performance, to determine where on each arc the calculated burst frequency offset fit best.

The analysis showed poor correlation with the northern corridor, but good correlation with the southern corridor, and depending on the ground speed of the aircraft it was then possible to estimate positions at 0011 utc, at which the last complete handshake took place. I must emphasise that this is not the final position of the aircraft.

There is evidence of a partial handshake between the aircraft and ground station at 0019 utc. At this time this transmission is not understood and is subject to further ongoing work.

No response was received from the aircraft at 0115 utc, when the ground earth station sent the next log on / log off message. This indicates that the aircraft was no longer logged on to the network.

Therefore, some time between 0011 utc and 0115 utc the aircraft was no longer able to communicate with the ground station. This is consistent with the maximum endurance of the aircraft.

This analysis by inmarsat forms the basis for further study to attempt to determine the final position of the aircraft. Accordingly, the malaysian investigation has set up an international working group, comprising agencies with expertise in satellite communications and aircraft performance, to take this work forward.

In annex i (attached) there are three diagrams, showing:

Doppler correction contributions

this diagram shows the doppler contributions to the burst frequency offset.


Mh370 measured data against predicted tracks

the blue line is the burst frequency offset measured at the ground station for mh370.

The green line is the predicted burst frequency offset for the southern route, which over the last 6 handshakes show close correlation with the measured values for mh370.

The red line is the predicted burst frequency offset for the southern route, which over the last 6 handshakes does not correlate with the measured values for mh370.


Example southern tracks

this shows the southern tracks for a ground speed of 400 and 450 knots ground speed. It should be noted that further work is required to determine the aircraft speed and final position.

http://s11.postimg.org/5sg7jcbjj/10155641_740971715947844_878199468_n.png (http://postimg.org/image/5sg7jcbjj/)http://s11.postimg.org/bunu9tzzj/10155041_740971712614511_1614955617_n.png (http://postimg.org/image/bunu9tzzj/)http://s11.postimg.org/b6ezqw19r/1525257_740971732614509_298214666_n.png (http://postimg.org/image/b6ezqw19r/)

Source: https://www.facebook.com/permalink.php?story_fbid=740971779281171&id=178566888854999

[OleOle]

oldoberon
MAS no satellite contract...

Has that been positively established? I remember this a one of the statements to be debunked afterwards. For example this "source" says:

“It is Mas procedure to switch ACARS, VHF, and High Frequency selection off but this is only for flights to China as the service provider for Mas does not cover China. Some if not all pilots switch them all off for a while and then later switch SATCOMM back on to force the system into SATCOMM mode.”

MISSING MH370: ACARS cannot be disabled - Latest - New Straits Times (http://www.nst.com.my/latest/font-color-red-missing-mh370-font-acars-cannot-be-disabled-1.521314)

[under_exposed]

Quote:
@syseng68k
It's actually much easier to recover data from over-written digital media. FBI software can recover data from digital media that has been over-written multiple times, or reformatted repeatedly.
Absolutely false. As mentioned before, it is simply impossible to recover any physically overwritten digital information.
While there is a theory that this is possible, nobody has been able to demonstrate being able to recover significant amounts of data.

[Pontius Navigator]

I see that Inmarsat have used a speed of 450 kts for their calculation. Assuming that a 777 operates at 0.84 or there abouts that equates to a TAS closer to 500kts.

How would that affect the arcs that they have published and how far down those arcs the aircraft might have flown.

What is the T7 range speed? It would not be 'thereabouts'; it is either 0.84 or it isn't.

The speed of 450 kts groundspeed predicates a constant wind iro 60 kts head wind assuming an OAT of -40C and my memory and calculation being correct which give a TAS of 510.

[APLFLIGHT]

@A69 could you please provide us with the official source/weblink of the "AAIB summary" ?

[OleOle]

Regarding the yellow and the red track on the aaib image/globe.

- Yellow represents the solution which covers the greatest distance, red the solution for smallest distance?
- Yellow is great circle, red is constant magnetic heading?

Together with the search areas that points to great circle solution, i.e. FMC and not to A/P => deliberate action?

Edit: Thinking about it, there could be a solution with 450 knots and constant magnetic heading which is much closer to the yellow track => deliberate action not confirmed

[OPENDOOR]

I think the idea of EPIRBs is not the best way forward. I would think more about using the satellite broadband link. Audio feed parallel with a CVR channel, 48 kb codec (G722 or similar would give enough audio bandwidth to ID warning tones) add a 2kb slow data channel for an integrated GPS data. Add error correction and you could fit 2 into the minimum broadband link.
Activation could be for example an aircraft loses ADS-B, VHF comms, departs flight plan, departs cleared altitude etc then ATC could poll the aircraft and switch on the CVR link.
Automatic battery back up incase of power failure.

The issue will be with how those in the cockpit feel about possible remote monitoring of anything they say?

ionagh; with respect (and I mean that) your proposal is not proof against tampering or catastrophic failure of the a/c

A fiber optic cable run from the AIMS unit to a internal hull mounted data exchange/charging/monitoring device constantly updating the external EPIRB/data recorder would provide a truly independent resource for SAR/AAIB people. No CVR snooping either.

It wouldn't need ED-12 certification as total failure would not affect the a/c

(yes, I did look it up)

ED-12B
Software Considerations in Airborne Systems and Equipment Certification
Latest Revision December 1, 1992

[Capt Kremin]

Together with the search areas that points to great circle solution, i.e. FMC and not to A/P => deliberate action?

Ole ole, looks like it.

It also looks like the green track on the graphic I put together, the western route using a constant magnetic hdg, as suspected, does not match any track which would correlate with the hourly satellite pings.

[A69]

@A69 could you please provide us with the official source/weblink of the "AAIB summary" ?
Yes, It's on the facebook page of Ministry of Transport Malaysia.
Here's the link https://www.facebook.com/permalink.php?story_fbid=740971779281171&id=178566888854999

[OleOle]

In the doppler shift diagram there are three bursts close to where MH370 turned south between ~ 18:20 -18:30 utc. If that is not just symbolic, it would indicate turning south happened in that time window.

- Why three burst in such a short time?
- And wasn't last PSR contact at 18:40 utc (2:40 MYT)?

[FastFlier]

BBC are reporting a final partial Inmarsat handshake ping received at 08:19 following the routine handshake received at 08:11 with no explanation. I'm not familiar with 777 systems, but could this have resulted from a transient power interruption during bus transfer following the loss of a genny?

[Methersgate]

Small objects, and objects that that are floating "high", will be subject to surface drift, the wind and wave derived motion of the uppermost layer of sea water, which is typically in the direction of the surface wind and should be applied after allowance is made for the current. In an areas such as the one under consideration, the surface drift can be quite fast.

[OleOle]

Capt Kremin

Ole ole, looks like it.

It also looks like the green track on the graphic I put together, the western route using a constant magnetic hdg, as suspected, does not match any track which would correlate with the hourly satellite pings.

Actually on second thought I think we still don't have enough data to jump to conclusions. The aaib tracks mark just the two extreme possibilities. There might as well be a constant magnetic heading solution with a higher speed and a more westward heading than the red track. That would end up much closer to the great circle (yellow) solution.