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Malaysia Airlines Flight 370: Experts Unable To Replicate Inmarsat Analysis 245

Posted by samzenpus
from the mystery-continues dept.
McGruber (1417641) writes "The lynchpin of the investigation of the disappearance of Malaysia Airlines Flight 370 has been the pings from the plane to one of Inmarsat's satellites. The pings are the sole evidence of what happened to the plane after it slipped out of radar contact. Without them, investigators knew only that the plane had enough fuel to travel anywhere within 3,300 miles of the last radar contact—a seventh of the entire globe. Inmarsat concluded that the flight ended in the southern Indian Ocean, and its analysis has become the canonical text of the Flight 370 search. It's the bit of data from which all other judgments flow—from the conclusive announcement by Malaysia's prime minister that the plane has been lost with no survivors, to the black-box search area, to the high confidence in the acoustic signals, to the dismissal by Australian authorities of a survey company's new claim to have detected plane wreckage. But scientists and engineers outside of the investigation have been working to verify Inmarsat's analysis and many say that it just doesn't hold up."
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Malaysia Airlines Flight 370: Experts Unable To Replicate Inmarsat Analysis

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  • An what? (Score:2, Insightful)

    by Noxal (816780)


  • by Anonymous Coward on Sunday May 11, 2014 @12:56PM (#46973375)

    The aircraft did not crash; it was hijacked by the US Government, and flown to Diego Garcia under remote control after all the passengers were killed by asphyxiation at 45,000 feet. After landing the plane was refuelled, its logos painted over/covered up, and its valuable cargo (next generation radios with SDR technology) removed. It then took off again and flew on to its final destination--probably Kandahar, Afghanistan--where it will be outfitted with a large bomb (read: nuke). It will then be flown into an American city to cause a 'false flag' attack which will be blamed on Iran, North Korea, etc, as a casus belli for World War 3.

    I would tell you more but som....hang on, there's a knock at the door.

    • by ColdWetDog (752185) on Sunday May 11, 2014 @01:11PM (#46973459) Homepage

      Yeah, that knock on your door is your mother.

      Time for your meds.

  • Who? (Score:3, Interesting)

    by Anonymous Coward on Sunday May 11, 2014 @01:06PM (#46973433)

    The author of the article claiming that experts cannot replicate the data appears to be the editor of a social science / STS journal, not by training an engineer. Although I don't myself know enough about the subject to be able to refute either the Inmarsat claims or this article's refutation, I think it's notable that the people supporting the claim are engineers who specialize in satellite stuff, while the person refuting the claim is what appears to be a philosopher; I'd also add that the author portrays himself as an "investigator working on Malaysia Airlines Flight 370", but this appears to be a self-assigned title rather than his position as part of any formal or professional investigation. Looking at the scholarship of the journal he edits, it appears to have some level of rigour--IE it does not appear to be a vanity publication, so I'm not trying to cast out the guy as a crank, just to caution that I think the strength and balance of the headline and the post here place an awful lot of confidence in the article's credibility.

    • Re:Who? (Score:5, Insightful)

      by ColdWetDog (752185) on Sunday May 11, 2014 @01:16PM (#46973477) Homepage

      TF Author is basically collating some information available on the web (we do that these days, you know). The original data that is attempting to refute INMARSAT's analysis is from two people (with blogs) which do have some expertise in the field:

      So it should be straightforward to make sure that the math is right. That’s just what a group of analysts outside the investigation has been attempting to verify. The major players have been Michael Exner, founder of the American Mobile Satellite Corporation; Duncan Steel, a physicist and visiting scientist at NASA’s Ames Research Center; and satellite technology consultant Tim Farrar. They’ve used flight and navigation software like STK, which allows you to chart and make precise calculations about flight scenarios like this one. On their blogs and in an ongoing email chain, they’ve been trying to piece together the clues about Flight 370 and make sense of Inmarsat’s analysis. What follows is an attempt to explain and assess their conclusions.

      Yes, this is an appeal to authority, but this is also a popular, non scientific, non peer reviewed bit of journalism. I'm not expecting much more.

  • by Anonymous Coward on Sunday May 11, 2014 @01:07PM (#46973439)
    If Inmarsat haven't released all of the data used in the analysis, why is anyone surprised that they can't recreate it?
  • Not so.... (Score:5, Interesting)

    by Anonymous Coward on Sunday May 11, 2014 @01:09PM (#46973451)

    Not so. These critics may or may not be correct when they raise several issues, including the plane seeming to be moving at a good clip before it was taking off. But on the most critical of factors, they're totally wrong:

    "Recall that the Marco-Polo math alone doesn’t allow you to tell which direction pings are coming from. So how could Inmarsat claim to distinguish between a northern and southern path at all? The reason is that the satellite itself wasn’t stationary."

    No, the slow drift of the satellite wasn't a factor. I've yet to hear Immarsat formal statement of their rationale, but their graph shows quite clearly what it was. Their reasoning hinges on the fact that the plane began its deviant flight above the latitude of the satellite. That is quite important.
    If the plane flies northward along a relatively fixed course, the doppler shift will aways show it moving away (down doppler). However, it the plane flies southward on a steady course, there'll be a short time (one ping it turns out) when it is approaching the latitude of the satellite and thus giving a more up (or less down) doppler. That's what you see in the Immarsat chart. Once the aircraft has crossed the satellite's latitude, then its southward path will have it traveling away from the satellite just like the northern route. It's that notch DOWN at between 18:30 and 19:30 followed by a rise upward that says southbound.
    That said the critics do raise some relevant issues and they do point out the Immarsat needs to release a detailed report with all their reasoning, so it can be more intelligently critiqued.

    • Re:Not so.... (Score:5, Informative)

      by Anonymous Coward on Sunday May 11, 2014 @01:45PM (#46973659)

      The problem with this analysis is that the Doppler "spike" would not have come from a due South trajectory. It is most likely to have come from a change of trajectory almost directly towards teh satellite. The implication is that this was a "ping" that just happened to have occurred during a turning manouevre; given that the SATCOM terminal on the aircraft uses a high-gain steerable antenna, it is not surprising that an "unscheduled" ping took place during a turn, as the beam-steering unit reacquired the satellite.

      The other massive confounder with this analysis is that the SATCOM terminal necessarily pre-compensates its transmissions for Doppler shift. The channel bandwidth in the Inmarsat Classic Aero system is sufficiently narrow that when received at the Satellite, the center frequency must be +/-250 Hz of nominal. As Doppler shift due to the expect motion of an aircraft is in the region of +/- 800 Hz, this can only be done by active pre-compensation.

      You'll notice from the Inmarsat Data that the uncorrected Doppler shift is within 250 Hz of expected, indicating that some pre-compensation is present.

      Without details of how the compensation works, analysis is very difficult, if not impossible. A scan of the patent literature suggests that both measured-Doppler compensation (i.e. the aircraft terminal measures Doppler shift on a satellite broadcast channel, and applies an equivalent compensation on its transmissions) and estimated Doppler compensation (i.e. the satellite terminal communicates with the aircraft's navigation reference unit to obtain heading, and velocity information, and then computes an expected Doppler shift which is applied to transmissions) may be in use.

    • Inmarsat also has a satellite over the pacific which (according to the picture []) covers the southern arc. Why couldn't they triangulate from both satellites?

      Further, the Jindalee Operational Radar Network in Australia is an over the horizon radar capable of sensing a four seater airplane like a cessna from 2600km away. Why didn't they see a plane 6-8 times larger and several hundred kilometers closer?
      • Re:Not so.... (Score:4, Interesting)

        by Anonymous Coward on Sunday May 11, 2014 @11:16PM (#46976433)

        Couple of possibilities:

        1) They did and they are not saying. Seems unlikely as the fact that Jindalee can, for example, track commercial airliners all the way from Singapore, is pretty much common knowledge.
        2) They didn't track it because they couldn't. Sadly, despite the money spent on it, Jindalee is great when it works, but unfortunately it doesn't work all the time. This partly explains why Australia has had to buy expensive AWACS aircraft as well as spending big money on Jindalee.

  • I've yet to see a reasonable explanation for the loss of telemetry and apparent maneuvers to avoid radar.

    So far the implicit assumption is that whoever was at the controls failed in their plan and the plane crashed.

    Considering the Indonesian 'navy' is a bunch of pirates, I would start by looking there.

    We still don't know what was in the cargo hold or if there was a billionaire on board. Did that plane have a richer suite?

    • by fermion (181285)
      Following the pings was a good method. The assumption made, as far as I can tell, was that there was no change in the flight path after the last ping was received. So we do not know that the methodology was wrong. In this the 'correctness' of the methodology would not be reproducibility, but success in locating the plan. So, on this case it appears the method may be 'not correct' but that is not necessarily because the analysis is invalid, but because the assumptions are incorrect. If a new analysis on
      • All manner of assumptions tied into interpreting the pings. Airspeed/altitude and straight line course are all assumed to get 'the place'. Flying low and slow and landing somewhere in Java also fits the data. As I said up-thread a large number of piracy incidents every year involve the Indonesian navy. Air piracy is not out of their reach, and they own hangers big enough to hide a 777. But they wouldn't do it just for the plane. There had to be something or someone special on board.

        Initially I assumed th

    • I've yet to see a reasonable explanation for the loss of telemetry and apparent maneuvers to avoid radar.

      There are reasonable explanations, just not innocent ones.

    • by camperdave (969942) on Sunday May 11, 2014 @04:14PM (#46974417) Journal

      We still don't know what was in the cargo hold or if there was a billionaire on board. Did that plane have a richer suite?

      We do know that Freescale Semiconductor, a US technology company having ties to both the Bush family and the Bin Laden family, had 20 senior staff on board Malaysia Airlines Flight MH370. They had just launched a new electronic warfare device for military radar systems in the days before the Boeing 777 went missing, which caused it's stock prices to nearly double in the month prior to the crash; stock prices which have been steadily declining towards their previous levels since the bluefin failed to find wreckage.

      Does that count?

      • > blah blah stupid blah blah nearly double tinfoil aliens

        Going from $20 to $23 is not "double". Google "Freescale Semiconductor chart" to see the stick price. Everything else you said is equally as accurate.

      • by Sockatume (732728)

        The actual conspiracy theory is that it's five people at Freescale who are authors on a particular patent, and it's not true anyway, but it's funny to see how this one has mutated. []

  • I DON'T CARE! (Score:4, Interesting)

    by loony (37622) on Sunday May 11, 2014 @01:23PM (#46973519)

    40K people die every day of hunger and the while the USD 60M or more that were spent so far on this stupid search couldn't have prevented that, it would have helped a lot of people have another chance.

    Either you say you care about the lives of people and then you just shake your head about this pointless waste of money or you don't care and then you wouldn't care about ML370 either. But you unless you're related or friends of anyone onboard that flight, you're just a for caring about the lives lost there and not about the people that die every day of hunger, war, and such...


    • Re:I DON'T CARE! (Score:5, Insightful)

      by ColdWetDog (752185) on Sunday May 11, 2014 @01:32PM (#46973581) Homepage

      It's really not about the people on the plane. It never has been past the first few hours.

      It's about a world wide industry that doesn't like expensive bits of it fall out of the sky for no reason. It's also not about the money. Hell, we could shut down an aircraft carrier battle group and feed the entire planet for a decade - don't look to humans to be rationale about that issue and don't try to conflate them.

      • by loony (37622)

        Yes, you're partially right on that but in my opinion there are enough other incidents that can yield data - missing one is really not that major.
        Also, if you listen to the news casters and articles written, they all at least pretend its about the human factor, not about analyzing the wreckage to see what caused the issue so we can prevent it in the future...


        • Re:I DON'T CARE! (Score:5, Insightful)

          by jimicus (737525) on Sunday May 11, 2014 @02:35PM (#46973935)

          Yes, you're partially right on that but in my opinion there are enough other incidents that can yield data - missing one is really not that major.

          Not regarding the Boeing 777 there haven't. There's only been seven accidents, and only one prior to MH370 that involved any fatalities. And if the cause was a fault with the plane rather than human error/intervention, it's important to know because there's a whole bunch of other, more-or-less identical aircraft in use and it's entirely possible that one or more of them has the same problem.

          • To the original poster's point though even if we lose a 777 every 20 years due to a design flaw, the money is better spent feeding the 20,000 people who die every day of starvation.

            But to be the rebuttal to that:
            If it costs $350m to find the fault with this plane then it'll still be a net win for the starving people. If the plane also costs $350m and this saves 2 planes over the next 30 years of service then you've netted an extra $350m in savings that could be put towards saving starving people. And i

      • Re:I DON'T CARE! (Score:5, Insightful)

        by fuzzyfuzzyfungus (1223518) on Sunday May 11, 2014 @03:16PM (#46974135) Journal
        In general, people seem to have a strong distaste, often backed by substantial investigative resources, for mysterious mysteries cropping up in the course what what is supposed to be a routine and mature process.

        Commercial aviation (at least the large-aircraft stuff, stats for dinky little aircraft are less reassuring) is ordinarily so well hammered out that basically every air crash has a strong element of mystery to it and so the investigators come and try to figure out what went wrong.

        Compare to cars, which kill plenty more people (and, unlike malnutrition and ghastly tropical parasites) people we usually care about; but still get minimal investigative attention because so many of the accidents are either 'operator was piss-drunk and/or exhausted', 'operator was flagrantly disregarding the rules for that area of the road', or 'vehicle maintenance was somewhere between horrendous and nonexistent'.
    • It doesn't matter if you care or not, it only matters that Wolf Blitzer still cares.
    • 40K people died of laws and organizations preventing them from getting food. There is enough food for everyone, there is enough will for people to provide for themselves and those that can't. This isn't 400BC anymore, people die of starvation because of bad policy, not because natural limitations. I'm not saying we shouldn't voluntarily feed them, but feeding them fixes nothing and by itself can actually make the problem worse. It's like giving someone painkillers instead of medicine.

      • by jythie (914043)
        Which is one of the reasons people get so worked up about things like missing planes, events like this are simple by comparison, even the most convoluted conspiracy theories require very little background in pretty much anything to grasp and they all have nice easy to blame forces behind them that do not point back to the speaker.

        Hunger and poverty on the other hand are highly complex issues with no clear force behind them and contain many elements that loop right back to our own lives and priorities. S
    • Re:I DON'T CARE! (Score:4, Insightful)

      by evilviper (135110) on Sunday May 11, 2014 @03:53PM (#46974317) Journal

      40K people die every day of hunger and the while the USD 60M or more that were spent so far on this stupid search couldn't have prevented that, it would have helped a lot of people have another chance.

      For every $6 cup of coffee you buy, you're KILLING a person. For every $300 TV you buy, you're killing dozens. Every month you pay for cable TV, you're killing a handful. Is that about right? Because lack of monetary handouts are the ONLY cause of all those deaths? Political instability doesn't have anything to do with it, and/or could be fixed with a small influx of cash?

    • by Ecuador (740021)
      Apart from the fact that finding what caused a hull loss helps preventing future accidents, I would certainly give a buck to find out what happened just out of curiosity and I bet at least 60 million other people would as well. That is on top of the 30 bucks I give every month to help combat hunger, and various other charities. It is not one or the other. If you want to find wasted money, look at the military. USD 60M is what the military would throw on a toilet cover.
    • If this was a different airline let's say Aeromexico or Turkish Airways and the plane left NYC mostly full of Americans I bet you'd care a lot more.

      In addition to the lost lives and the price of the airplane there are considerable political ramifications as well.

  • by SuperKendall (25149) on Sunday May 11, 2014 @01:26PM (#46973537)

    I think it's pretty interesting that a number of devices detected pings, but there is apparently (as per the article) nothing was found in the area where they heard the pings.

    So what did they hear? How can you get a false positive on a listening device looking for a specific frequency?

    I wonder if instead of just sending out pings, a black box when hitting water should send out a burst of broad spectrum very high powered radio waves that satellites around the globe could detect...

    • The devices were not looking for "a specific frequency", and, in fact, the detections were not at the frequency the FDR/CDR were supposed to send. They were "close", and part of the reason they had confidence in the finding is that after AF447 was found, they tried out the transmitter and noted that the frequency was off by a little.

    • by hey! (33014)

      I think you're conflating the satellite pings sent by the plane's maintenance system to satellites and the ultrasonic "pings" that the submerged flight data recorder is supposed to generate. Right now there's nothing particularly mysterious about the fact that we can't locate the wreckage of the plane in the middle of millions of square miles of featureless ocean.

      In any case, the simplest answer is to have planes transmit a GPS fix a couple times per hour to a satellite communication network. The cost would

      • I think you're conflating the satellite pings [...] and the ultrasonic "pings" that the submerged flight data recorder

        Chinese and Australian searchers picked up possible sonar pings from the FDR beacon. But were unable to confirm the findings enough before the beacon died.

        In any case, the simplest answer is to have planes transmit a GPS fix a couple times per hour to a satellite communication network. The cost would be negligible compared to the overall operation cost of the airplane.

        Yeah. It stuns me that they don't have position pings once every fifteen minutes (plus twice more on heading, speed and altitude changes.) It would revolutionise aircraft S&R.

        Hell, why don't large aircraft transmit position, heading, airspeed, altitude, etc continuously to their home organisations? The bandwidth required is trivial, a few kb/s would b

      • On a re-reading I can see how you might think I was confused, but Fat Monkey there mentioned the pings I was thinking of, which were sonar pings detected (and from which they have found nothing from a 150 mile search area the pings were supposed to come from).

    • Why didn't they use a UAV to home in on the pings like a missile, rather than gridding in on the source using a passive device?
  • data retention (Score:4, Interesting)

    by bugs2squash (1132591) on Sunday May 11, 2014 @01:27PM (#46973543)
    The satellite transponder is just an amplifier and a modulator, things go up one frequency and come down another frequency and louder. The satellite and the transmitter are in motion relative to each other and the receiver. Hence there is Doppler and my understanding is that the analysis of the Inmarsat data was based on this Doppler. So does Inmarsat record and retain sufficiently detailed information about every signal sent through their satellites such that they can deduce their findings from analysis of played back signals, or are they managing the receiver in this case and analyzing the log from the receiver.
  • Spy games (Score:4, Insightful)

    by mrflash818 (226638) on Sunday May 11, 2014 @01:30PM (#46973563) Homepage Journal

    In a world where spy satellites have 1m resolution, the fact that no country says they found anything within a few days, speaks loudest.

    • Why would any country dedicate valuable spy satellite time and resources to searching for an airliner?

      • Why would any country dedicate valuable spy satellite time and resources to searching for an airliner?

        Why wouldn't they? I can think of nothing that says "We can see everything you do" better than finding aircraft debris in a case like this.

        • Re:Spy games (Score:5, Informative)

          by Richard_at_work (517087) <[richardprice] [at] []> on Sunday May 11, 2014 @04:57PM (#46974645)

          The why not is an easy one - spy satellites are put into orbits which cover the likely hotspots for their use, and changing those orbits lessens the useful life of the satellite fairly significantly.

          Oh, and no one really wants to give away the true capabilities of their spy satellites...

          • I can see why they wouldn't want to exhibit their shortcomings, or their full capabilities, but why not a few 1 metre resolution demonstrations of how well they can see you if they wanted to? After all, the occasional demonstration of capabilities is required to maintain the threat value of the military, and it's public knowledge (declassified information) that the US spy satellites had 1m resolution capabilities back in the late '60s. As far as useful life, the X37B does refuelling runs*, so no big deal
          • The why not is an easy one - spy satellites are put into orbits which cover the likely hotspots for their use, and changing those orbits lessens the useful life of the satellite fairly significantly.

            Oh, and no one really wants to give away the true capabilities of their spy satellites...

            Not true at all. Reconnaissance satellites are usually on very low near-polar orbits, completing an orbit in 60-90 minutes. As the Earth spins below, they cover the whole thing. However, the sensors onboard collect more data than the available bandwidth, so they do not transmit the data about uninteresting areas, such as over the open ocean where nothing of interest is expected to be.

            You could make a point for storing a 48 hour buffer of all untransmitted data for later transmission if it is deemed necessar

    • Apparently no one has their spy satellites focused over empty ocean.
  • by FirstOne (193462) on Sunday May 11, 2014 @01:36PM (#46973603) Homepage

    Like the signal reflecting off the ocean below instead of coming directly from the aircraft.

    The only sure way to is to duplicate the flight path with a similar size aircraft using the same Engines and monitoring stations, using similar SAT positions. Only this time use a plane with extended range 777-200LR(verses missing 777-200ER) with minimal payload&maximum fuel and/or safely replicate the flight path in sections.

    Use the resulting SAT/GPS data to help calibrate mh377 final resting spot.

  • by BoRegardless (721219) on Sunday May 11, 2014 @02:09PM (#46973783)

    They are already writing their books, guaranteed

  • Couldn't one look at the satellite ping data from MH370 from a week earlier or whenever the latest "good" flight was and compare ping data of the doomed flight? Also look at ping data from a flight that matches close to the flight path of the projected path of the doomed flight and see if satellite ping theory is actually plausible. That's one way to narrow down the possibilities.
  • by statemachine (840641) on Sunday May 11, 2014 @05:57PM (#46975053)

    The article is irrelevant since the ocean floor around the pings is still being searched.

    Since the article can't even get a basic fact correct, I don't even trust their analysis.
    But now the search of 154 square miles of ocean floor around the signals has concluded with no trace of wreckage found. Pessimism is growing as to whether those signals actually had anything to do with Flight 370. If they didn’t, the search area would return to a size of tens of thousands of square miles.

    The link the article uses to "prove" that says something different:
    The hunt for a missing Malaysian passenger jet entered a new phase as an international team abandoned its aerial search and said efforts to find wreckage on the ocean floor may take as long as eight months. []

    It looks like slashdot just linked to another conspiracy theory. Please quit doing that.

  • by AC-x (735297) on Sunday May 11, 2014 @06:10PM (#46975125)

    Until officials provide more information, the claim that Flight 370 went south rests not on the weight of mathematics but on faith in authority

    Wasn't the main evidence against a northern path the fact that the plane would have to have flown over some (unlike Malaysia) heavily monitored airspace?

  • by saigon_from_europe (741782) on Sunday May 11, 2014 @06:18PM (#46975169)

    The company claimed that they have confirmed their methodology using data from other airplanes flying in similar area.

Have you ever noticed that the people who are always trying to tell you `there's a time for work and a time for play' never find the time for play?