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United Kingdom Transportation Technology

How Satellite Company Inmarsat Tracked Down MH370 491

mdsolar (1045926) writes "Malaysian Prime Minister Najib Razak has announced that, based on satellite data analysis from UK company Inmarsat, Malayian Airlines flight MH370 ended in the southern Indian Ocean, and no one on board survived. 'Effectually we looked at the doppler effect, which is the change in frequency, due to the movement of a satellite in its orbit. What that then gave us was a predicted path for the northerly route and a predicted path the southerly route,' explained Chris McLaughlin, senior vice president of external affairs at Inmarsat. 'What we discovered was a correlation with the southerly route and not with the northern route after the final turn that the aircraft made, so we could be as close to certain as anybody could be in that situation that it went south. Where we then went was to work out where the last ping was, knowing that the aircraft still had some fuel, but that it would have run out before the next automated ping. We don't know what speed the aircraft was flying at, but we assumed about 450 knots.' Inmarsat passed the relevant analysis to the UK Air Accidents Investigation Branch (AAIB) yesterday. The cause of the crash remains a mystery."
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How Satellite Company Inmarsat Tracked Down MH370

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  • Executive summary... (Score:5, Informative)

    by Last_Available_Usern ( 756093 ) on Monday March 24, 2014 @01:14PM (#46565145)
    We still have no idea exactly where the aircraft is, how it went down, or what to do now.
  • Little disturbing (Score:5, Interesting)

    by kid_wonder ( 21480 ) <> on Monday March 24, 2014 @01:15PM (#46565155) Homepage

    Did the Malaysian government just make a statement to the families based on a statistical probability?

    Or did they make that statement based on debris found that was positively identified to the aircraft.

    • Re: (Score:3, Informative)

      by mdsolar ( 1045926 )
      Based on the analysis of the satellite data.
    • The Malaysian government has mishandled communication from the start. I think they just want this whole thing over and done with. The ones in power over there aren't exactly used to being criticized like this.

    • by idji ( 984038 )
      The Malaysian government made the statement based on Inmarsat calculations, not on debris.
    • by khb ( 266593 )

      The published text of the PM's speech makes it clear its based on the analysis (what you are calling "statistical probability") not debris or black box.

      I don't know why anyone would find that disturbing.

      Even if he had debris, for any given family there would still be some "statistical probability" that their loved one survived (infinitely close to zero) involving some sort of miracle, a hidden parachute or a missed connection, etc. Just as we'd discard such false hope, pretending that there is some other pl

      • by bluefoxlucid ( 723572 ) on Monday March 24, 2014 @02:05PM (#46565705) Homepage Journal

        I don't know why anyone would find that disturbing.

        In Tres Roeder's "A Sixth Sense for Project Management," he shows a diagram of communications. This diagram shows information versus time.

        In the beginning, information is unknown; then the information changes, back and forth. For example: a dollar estimate may be $3,000 for a project, then $85,000 when we realize we need to excavate cabling tunnels for a line, then $6,000 when we realize we can run this across our existing tunnel and have a new fiber optic pulled for $3,000, then $7,000 when we realize we're going to also need a new transceiver, then $4000 when we find out some of the other equipment is unnecessary, then $14,000 when we realize the scope of labor required is twice as big.

        Finally, once we have enough information, that figure stays. Perhaps at $14,000. We also realize we've got the correct figure because we have a full analysis of scope and work required--or at least, the figure won't change until we've done a bunch of work and realized, deep into the project, that we missed something. In any case, it is now not likely to change simply because our information base is hot.

        During the initial planning phase, communication should reflect this: the understanding of the situation--the lack of precision--and what is being done to pin that down is to be communicated; conclusive statements should not be communicated because the current understanding of the situation is inconclusive. Once the situation has reached a point of conclusion, then you communicate these conclusions.

        What is disturbing about the Malaysian government here is they have been repeatedly saying, "We have no idea what's happening and there's a ton of information out there we're missing; but this is what happened." Then, five hours later, "Oh we found more debris, we think this happened instead." Then the next day, "Oh there was some satellite telemetry information we weren't done analyzing, but it's provided additional information, so we think the plane may have gone this way..."

        In other words: They have piles of information they know they're missing, piles of information they have a plan for finding (i.e. "ongoing investigation"), and huge and visible gaps they know exist and expect to fill. They should not be communicating any conclusions at this time.

      • There are supposed to be several salt-water activated beacons that should have been activated. You don't find it disturbing that every one of those failed?

    • by Zocalo ( 252965 ) on Monday March 24, 2014 @01:31PM (#46565313) Homepage
      Inmarsat managed to eliminate the northen arc based on differences in expected doppler differences of the signal pings, when the last ping was received, and assuming a conservative fuel consumption to that point, there would have been insufficient fuel left for the plane to make land, hence it went down in the ocean. It's important to note that Inmarsat is unable to say where exactly, only that it is within a given range of the location where last known ping was now known to have been sent from, which is where the search for wreckage is now centred. I gather this is the result of a highly unorthodox set of data analysis that is well outside normal procedures for determining location, hence the reason it's taken so long - some of the techniques they used probably haven't ever been done before.
  • by GodfatherofSoul ( 174979 ) on Monday March 24, 2014 @01:27PM (#46565265)

    It just seems like they have information that still doesn't make sense for what we're told are the available resources. The public info just seems so selective as if each government is trying to hold their surveillance cards as tightly as possible. And, intel from an old satellite seems like a cover story. This is all just

    • by SydShamino ( 547793 ) on Monday March 24, 2014 @01:37PM (#46565385)

      I thought that maybe a bunch of spy satellites picked up and stored the broadcasts, and that they can use timestamps from the various receptions to triangulate the position. That's sort of a reverse-active GPS.

      Of course they'll never say "we got this from U.S. and British spy satellites" so they make up something about doppler shift data from a single satellite and hope they find the debris soon to corroborate the story.

      Or maybe they did do it all from the doppler shift data they happened to store. It's at least plausible, and there's no need to create conspiracy theories when they aren't particularly shocking.

    • This [] is the most credible explanation I've seen thus far. (It was mentioned here a few days ago, but I'm too lazy to track down the link right now.)

      • To summarize:

        Fire on board the plane.
        Pilot diverts to the nearest safe airport (which is approximately line with the sudden course change to the west).
        Flight crew runs through the fire checklist, which includes pulling all the breakers in case it's an electrical fire (Transponder and communications lost).
        Fire causes decompression, pilots bring the plane down to 12,000 ft to remain conscious and keep the passengers alive.
        Crew is overcome by smoke and/or decompression, plane flies on under auto-pilot until it

    • Yes.. this whole incident is going to make great fodder for conspiracy theories for years to come at this rate.

      I would like to coin the theory right now that there was a second plane that extracted all the passengers mid flight and carried them the rest of the way. After everyone was taken off the plane it was allowed to fly on until it ran out of fuel.

    • by icebike ( 68054 )

      There is very little reason to have spy satellites in the south Indian ocean.
      Inmarsat is one of the few companies needing coverage down there because they have the contract for ACARS data an occasional sat phone calls. This area is not even on normal shipping routes.

  • Mystery? (Score:5, Insightful)

    by alta ( 1263 ) on Monday March 24, 2014 @01:29PM (#46565291) Homepage Journal

    The cause of the crash isn't a mystery. It most likely ran out of fuel.

    The cause of why the whole damn plane went AWOL IS a mystery.

    • If it simply ran out of fuel, it should have made controlled water landing and likely floated, with plenty of people exiting the plane with life vests on.

      • It's virtually impossible to land a large plane in the water "safely"; if either wing or engine touches the water before the other, that side digs in and the plane cartwheels, ripping itself to shreds.

        The hudson plane landing wasn't a miracle because of skill on the part of the pilot - it was a miracle because it was astronomically slim odds that the plane would continue in a straight line and remain intact.

  • by dtjohnson ( 102237 ) on Monday March 24, 2014 @01:36PM (#46565373)
    The calculations show the southern flight path and consequently a water landing. can they be so certain that no one survived? Isn't it possible that the airplane made a controlled glide into a non-powered water landing and that the life rafts deployed and allowed some of the passengers to survive? That has happened before. Admittedly this is very unlikely but can anyone at this point say it is impossible as the Malaysian government is doing?
    • Yes, that could be. But it seems clear that the plane was not being controlled by anyone who wanted the plane or its passengers to be rescued, so "oh, I've just flown the plane as far away from civilization as possible and I've just run out of fuel, yet I think I'll try at the last moment to make a successful water landing so as many people as possible can be saved" just does not seem likely. Either the plane was not under control, or those in control were not trying to save anyone.

      And more specifically I s

    • by dj245 ( 732906 )

      The calculations show the southern flight path and consequently a water landing. can they be so certain that no one survived? Isn't it possible that the airplane made a controlled glide into a non-powered water landing and that the life rafts deployed and allowed some of the passengers to survive? That has happened before. Admittedly this is very unlikely but can anyone at this point say it is impossible as the Malaysian government is doing?

      Each life raft has an EPIRB [] which is marine rated, and can be picked up by sattelites basically anywhere on the planet. At least one EPIRB would be of the automatic type which starts transmitting when it hits water. The EPIRB is wrapped up deeply inside the packed life rafts, so disabling them would be impossible while the plane was in the air. Unfortunately this means that if the life raft doesn't deploy and instead sinks, the EPIRB will not go off. The fact that no EPIRB signals were transmitted indica

  • by BitZtream ( 692029 ) on Monday March 24, 2014 @01:37PM (#46565381)

    They have a theory, nothing more. Still no actual debris has been confirmed. They don't have the full picture so its REALLY easy for their theory to be wrong.

    God you suck ass at actually posting facts slashdot.

  • While that explanation is detailed and great and accurate, the real answer is they found out they'd get free advertising through all the press coverage and spent a ton of time and money finding it. That's the short version at least.
  • I may be wrong, but looking at the map it seems the plane was on exactly the opposite course from where it should have been going. Strange problems are not unknown with computer-controlled navigation systems going haywire when crossing the Equator, and oddly enough MH370 went AWOL quite close to the Equator... []

    • Sorry, the story I linked to related to the International Date Line not the Equator. I was thinking of the much older stories about an F-14 or F-16 that flipped upside down when it crossed the Equator due to some software bug. Here is a reputable source for that (but only as a rumour): []

  • by rockmuelle ( 575982 ) on Monday March 24, 2014 @01:52PM (#46565573)

    What's most interesting is that the anonymous reports from the US intelligence community the day after the plane disappeared said that the plane was on the bottom of the Indian Ocean. These claims seemed a little odd at the time since there was no supporting evidence at all and rescuers were still looking for debris on the original flight path. But, it's looking like they were spot on.

    I'm going to go out on a limb and suggest that the only real conspiracy in this whole affair is the US govt's cover up of the initial leak. The plane itself likely just suffered a catastrophic failure and lumbered on until it ran out of fuel. But, the US govt also likely tracked it the entire time. That's why someone was able to make a confident pronouncement so quickly. They knew exactly where the plane was, if not exactly what happened. But, this intelligence capability (tracking all flying objects all the time) is probably highly classified. Rather than give it up for a civilian SAR effort, they decided to keep it under wraps, knowing that eventually the plane would be found and the capability is far more useful if no one knows it exists.

  • Why? (Score:4, Insightful)

    by GameMaster ( 148118 ) on Monday March 24, 2014 @02:26PM (#46565931)

    * We've had flight recorders on all major airliners for decades now.

    * We've had satellite phone technology for decades now. (since 1979 for Inmarsat)

    Remind me again why "black box" style cellular data transmitters aren't required to be transmitting cockpit voice data and full telemetry from every major airliner at all times yet? With a system like that, installed in a way that can't be tampered with by the people in t he plane and runs independently of the rest of the electronics in the aircraft, there's no reason we would know the exact location the plane went down and, most likely, why. Hell, even if they decided to be cheap and only have it transmit the telemetry in once-a-minute updates we'd still would have know where the plane was to withing a handful of miles from the first day it went missing...

    • Remind me again why "black box" style cellular data transmitters aren't required to be transmitting cockpit voice data and full telemetry from every major airliner at all times yet?

      Because in the middle of the ocean, there are no cellular towers.
      You could do it with satellites, but that becomes cost prohibitive extremely quickly.

      Not to mention that there just isn't enough bandwidth to do what you're proposing for every plane.

      As a compromise, there's a company looking to put ADS-B [] receivers on satellites.
      That way, the existing line-of-sight radio broadcasts from planes can be tracked without an extensive ground based network.

  • by mdsolar ( 1045926 ) on Monday March 24, 2014 @02:27PM (#46565957) Homepage Journal
    This analysis seems to depend of a "last turn" and constant speed for reconstruction. That could turn out to be a bit circular since a Northern track would likely have some turns in it to avoid radar and some speed changes dealing with altitude changes. But, the speed estimate along the line of sight between the plane and the satellite might mimic the straight line assumption in the South if Bhutan were a way point before turning towards the China/Kyrgyzstan border area. You'd get the same small-followed-by-growing Doppler shift pattern. It would be good to know it they modeled paths of that sort in their analysis.
  • by shoor ( 33382 ) on Monday March 24, 2014 @02:51PM (#46566241)
    I found this article in the Christian Science Monitor to be very plausible. That was on March 18, when they were still looking all over the place for the plane, and it's a scenario that still holds up. Basically, something went wrong, the pilots started to head for the nearest airport, but then passed out. []
    • That was on March 18, when they were still looking all over the place for the plane, and it's a scenario that still holds up.

      That scenario stopped holding up once we found that the aircraft had maneuvered both vertically (changed altitude) *and* had undergone multiple changes to it's course. It also fails the sniff test as it fails to explain why the pilots didn't follow SOP and don their oxygen masks - which have microphones built into them. The reliance on "aviate, navigate, communicate" is also questio

  • by GumphMaster ( 772693 ) on Monday March 24, 2014 @05:21PM (#46568185)

    Effectually we looked at the doppler effect, which is the change in frequency, due to the movement of a satellite in its orbit.

    You can tell this is the PR guy and not the tech guy. Firstly, "Effectually"?

    Secondly. The Inmarsat-3 F1 satellite is geostationary, it moves little and slowly relative to the Earth's surface. There is effectively no doppler shift due to motion of the satellite relative to the Earth. The doppler shift here would be that of the aircraft relative to the Earth/satellite. The absence of doppler shifts is the reason that Copas-Sarsat geostationary satellites cannot determine surface position of a emergency locator transmitter unless the transmitter sends that information. For beacons that do not transmit location the low-Earth orbit Copas-Sarsat satellites, which have motion relative to the surface, are used to determine location by multiple doppler readings (but it takes up to 90 minutes vs. seconds).

  • by Snotnose ( 212196 ) on Monday March 24, 2014 @07:35PM (#46569625)
    Lets put on our paranoia hats for a minute. How hard would it be to hijack the plane, land it somewhere, lose everyone on board, make some debris from the plane, fly the debris to the Indian Ocean, and drop it off? I mean, if they've gone through the trouble of getting the plane and losing the people on it, how much harder is it to fake debris?

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