MH370 Search Area Moves Further South Again

ATSB search areaAt a press conference in Canberra today, Australian Deputy Prime Minister Warren Truss state that “further refinement of satellite data” indicated that missing Malaysia Airlines Flight MH370 had turned south earlier than investigators had originally thought. This implied, he said, that the plane had most likely would up further to the south than previously estimated.

The previous assumption was laid out in a report released in June by the Australian Transport Safety Board (ATSB), which included the map shown here. The document described a methodology for determining the search area which suggested that the plane did not make a single turn to the south and then fly on a straight-ahead course into the southern ocean, but rather lingered near western Sumatra for the better part of an hour.

After the report was issued, a loose coalition of experts from around the world called the Independent Group (of which I’m a part) released a statement which questioned the ATSB’s methodology, and in particular pointed out that signal data related to an attempted satellite phone call at 18.40 UTC indicated that the plane was already established on a course to the south. This fact allows the range of possible flight paths to be narrowed considerably.

As fate would have it, Truss’ announcement came just one day after the Independent Group issued a follow-up statement reminding the authorities that its own analysis suggested a search area futher to the south.

“The data is nothing new, but the fact that the Australian government has chosen to issue this statement is very interesting,” says Independent Group member Victor Iannello.

Truss was vague as to where the priority search area had shifted, saying it remained “within the search area” previously laid out in the southern Indian Ocean. This area, however, is more than 1,500 miles long.

260 thoughts on “MH370 Search Area Moves Further South Again”

  1. Matty-Perth,

    We just do not know if other satellites, other than Inmarsat IOR satellite, had also picked up the pings, because no one is saying anything.

    I will in the coming days post some thoughts on what appears to be a cover up involving some governments and the various aviation authorities.

    The evidence shows the plane crashed around 100 NM from IGARI on the path it was on at IGARI ie 40 degree, which works out to be around 30 NM off the south or south east of the southern tip of Vietnam.

    This part of the planet is covered by Inmarsat Generation 3 Indian Ocean Region satellite (IOR 64E). It also happens to be at the very edge of coverage of another Inmarsat Generation 3 satellite, the Pacific Ocean Region satellite (POR 178E). This area is also covered by the Inmarsat Generation 4 Asia Pacific satellite (at 143.5 E).

    I do not know if other companies’ satellites eg Iridium could actually pick up signals from other systems. But can one assume that Inmarsat’s other satellites did not detect the pings?

    This is one of the many questions that the authorities have to answer, preferably on oath.

  2. On the point about redundancy in SATCOM equipment.

    In principle, all avionics would be designed with redundancy in mind. So what is so special about the SATCOM system that to some of u, it should not or would not have any redundancy?

    As noted in previous comments, the B777 fitted by Honeywell belonging to Malaysia Airlines have 2 SDUs and 2 antennas, the dual configuration provided under ARINC 741. The 2 antennas can be observed from the pictures of the plane found on the net. So the people fitting the plane did have redundancy in mind for the SATCOM system.

    The following is a quote from a draft Iridium manual:

    “As all the avionics, the AES will be designed so that MTBF [mean time between failures] is as long as possible whereas MTTR [mean time to repair] is as short as possible. These two requirements will apply to essential airborne units such as the satellite data unit, communication management unit, beam steering unit and the antenna subsystem. This may be achieved by main/hot standby configuration of the critical units stated above, as well as automated change over mechanism within each unit.”


    It is true that under the Boeing 777 Electrical Load Management System (ELMS), primary power to the SATCOM system will be shut off in certain emergencies. However, we are not talking about primary power here, but whether the back up SDU had sufficient battery power from somewhere to respond to the satellite pinging. Furthermore, if indeed a lightning strike of high intensity had managed to penetrate into the plane, the AIMS and all other primary systems functioning at such time would have been knocked out and the wiring/cables fried, so there will not be any ELMS.

  3. Gysbregth,

    “The ATSB has described their reasoning in much detail supported with reasonable arguments”. [regarding the power interruptions]

    1. I beg to differ. The ATSB, in my humble view, failed miserably to explain their “2 power interruptions’ theory.

    2. Cheryl over on Duncan’s blog in her endearing straightforward way had posed this question: If for the ‘2nd’ power interruption at 00:19 UTC (8.19am) the ATSB says “following the loss of AC power on both buses, the SDU would have experienced a power interruption sufficiently long to force a shut-down, the aircraft’s ram air turbine (RAT) would deploy from the fuselage…. and the APU would auto-start…”, how come the same thing did not happen for the ‘1st’ power interruption prior to 1825 UTC? Ie why the RAT deployed and APU started only for the ‘2nd’ power interruption but not the ‘1st?

    3. The ATSB’s answer to this question is found in footnote 20 which reads as follows: “The earlier SDU log on request at 1825 UTC was also considered likely to have been due to a power interruption. As this power interruption was not due to engine flame- outs, it is possible that it was due to manual switching of the electrical system. Therefore it is possible that the aircraft’s electrical configuration was not in the normal state (ie the left IDG powering the left AC bus and the right IDG powering the right AC bus) at the time of the first engine flame-out.”

    Perhaps u can decipher what the ATSB meant and enlighten us.

  4. littlefoot,

    1. The brief search at the South China Sea was shambolic.

    2. The plane was at IGARI at 1.21am at 35000 ft when the SSR signal ceased and both ATCs continued to track the plane on primary radar until 1.30am up to BITOD.

    3. According to the ATSB Report, the maximum distance a B777 can glide unpowered is 120 NM.

    4. In the first 2 days, the search was limited to a radius of 20 NM from IGARI. From the Malay Mail, a Malaysian newspaper on March 9th:

    “After almost 2 days since MH370 lost contact with the air traffic control, DCA DG Datuk Azharuddin revealed tonight that the… search radius had been expanded. ‘ We have in fact intensified our search in the area. Initially it was a radius of 20 nautical miles from Igari, we have increased it to 50 nautical miles…”.

    5. On March 11th the New Straits Times, a leading Malaysian newspaper reported:

    “As the search and rescue (SAR) operations enters its fourth day today, the search area for MH370 over the South China Sea has been tripled to cover a 100 nautical miles radius from waypoint Igari… He said the search would be expanded even further the next few days if the [plane]was not found…”.

    6. The very next day Malaysia received the word from AAIB/Inmarsat that the plane had supposedly flown on for another 7 hours and the search at the South China Sea for all practical purposes was over. Vietnam said it was suspending its search and a couple of days later Malaysia officially abandoned the search.


    I have been trying, since the Malaysians abandoned the search at the South China Sea, to plead the case that they should complete the search there . By all means, search every other place if one thinks the plane could have ended at such other place, South Indian Ocean, Andaman Seas whatever. But why stop the search at the South China Sea when it barely got started? The plane disappeared there at 1.30am. No ATC saw the plane after that. No one has produced a recording of a radar track showing an unaccounted plane that night. Malaysia borders the South China Sea which waters are relatively shallow. Why not deploy some assets to complete the search at the South China Sea while other assets and countries search elsewhere?

  5. Alex,

    RE YR post at 10:23 PM Sept 8:

    The change of BFO for a stationary airplane was shown on the graph presented earlier. I have prepared a similar graph for the BTO:

    Both graphs show that the logged values of BFO and BTO differ from those for a stationary airplane, and that difference changes with time. You have no explanation for that difference, which is due to the fact that the airplane is moving and not stationary.

    The ATSB report in Appendix G states “The BTO measurement comprises two components: a bias component caused by fixed delays in the system, plus a variable component caused by the time taken for the outbound radio wave to pass from the GES to the aircraft and the inbound radio wave to make the return journey.” The SDU only adds a fixed delay to the time offset, it does not calculate anything for the BTO.

    RE YR post at 10:57 PM Sept 8:

    The ATSB report does not mention 2 SDU’s on a master/slave basis. Perhaps your reference is for another terminal? You write “the catastrophic event struck breaking the link between the primary SATCOM system and the satellite”, yet miraculously spared the back-up system and the wiring between the SDU and the antenna, but the back-up system was unresponsive at 18:03 and miraculousy became alive on its internal battery at 18:25 to send a Log-on Request?

    I leave the speculation about credit card data for what it is. Were these payments made after the “catastrophic event”?
    When the ATSB writes: “Similar messages would be expected after the 00:19 logon request, however none were received.” that is just rubbish?

    RE YR post at 11:45 PM Sept 8:

    I do not see the relevance of the telephone connection request being routed through Burum. The BFO was recorded on the message received from the aircraft in the GES at Perth.

    RE YR post at 4:19 AM today:

    What is not clear about:
    “As this power interruption [at 1825 UTC, to the left AC bus (GBRT)] was not due to engine flame- outs, it is possible that it was due to manual switching of the electrical system.”? Obviously another manual switching took place just before 1825 which restored power to the left AC bus, which powers the SATCOM system among others.

  6. @Gyesbreght

    Both graphs show that the logged values of BFO and BTO differ from those for a stationary airplane, and that difference changes with time. You have no explanation for that difference, which is due to the fact that the airplane is moving and not stationary.

    How many other BTO/BFO values have you reviewed for other stationary aircraft?

    For this aircraft?(historical data)

    I think I know the answer, but please respond anyway.

    BTW – This is why I requested historical data for MH370 and other aircraft for stationary/power-up and power-off scenarios. None of which has been provided.

  7. @All _ FYI

    I recently queried the ATSB asking them to indicate exactly why they have so far refused to publicly release the recordings of the putative acoustic “pings” re: MH370.

    ATSB referred me to the ADF and I am waiting for a reply from them.

    I will post anything I receive.

  8. Gysbreght,

    1. Let me try again. The SDU for the period of the pings was not functioning as normal. By Inmarsat’s own admission, various BTOs were off, some, way off. We are talking about a timing system here. The timing for some readings were off by 37%, the timing for others were off more than 300%. At least 4 out of the 14 readings were off, nearly 30%. If this timing system was working as normal and end up giving such errors, this has got to be worst timing system in the history of mankind.

    2. Other readings somehow end up mimicking the movement of the satellite. If the plane was moving and the satellite was also moving, how can the readings over a 6 hour period mimic the movement of the satellite? Either the plane was not moving or the plane was moving but the SDU was not accounting for the plane’s movement because it was not getting the information on the plane’s movement from the IRS/AIMS. Either way the readings cannot be the basis for saying the plane was moving during such period.

    3. The truth is no one outside of Inmarsat really knows what the BTO represents. Richard Cole did a paper before the ATSB Report came out. Perhaps Richard can opine as to whether what the ATSB says about the BTO is in accord with what he thought the BTO meant when he wrote his paper. Is it ‘a value relative to a terminal at a nominal fixed location’ as stated in the 47 page data log or is it ‘a measure of how long from the start of that time slot the transmission is received’ as stated at page 18 of the ATSB Report or is it the total of ‘a bias component caused by fixed delays in the system, plus a variable component caused by the time taken for the outbound radio wave to pass from the GES to the aircraft and the inbound radio wave to make the return journey’ as stated at page 54 of the ATSB Report? Or none of the above?

    4. The link between the SATCOM system and the satellite was broken by the catastrophic event. So in that sense, the SATCOM system had ‘logged off’. There was no formal log off like when the system is powered down upon arrival. If u look at the ACARS report for Swiss Air Flight 111, there was also no ‘log off’ but the SDU on that plane, from Honeywell as well, also made a log on request minutes before the plane crashed.

    5. The ATSB did not give any detail about the SATCOM system. No word as to the model, manufacturer, configuration etc. Neither did the Preliminary Report. In actual fact, the authorities have said absolutely nothing about the make-up of the SATCOM system. Which is more than a little strange considering this is the equipment that transmitted the pings upon which this whole 7 hour flight to the SIO theory is premised.

    6. The dual SDU dual antenna configuration is set out in the MCS Series manual. U can find it online. It is also provided under ARINC 741 which can also be found online.

    7. I have explained that the IFE data could have already been ‘in the queue’ waiting for transmission when the the link was broken and when the link was restored at 1825 UTC, the data went through.

    8. The fact that 6 hours later, there was no further IFE data supports the case that the plane had already crashed 6 hours earlier.

    9. As discussed in a previous comment, the Doppler correction for a C Channel can be done in a number of ways, one of which is through the open loop system by using a pilot signal. The BFO for the attempted call could have been calculated from this pilot signal which may be of a different frequency than the frequencies used by the other GES at Perth. But what do I know.

    10. What is this manual switching the ATSB was talking about and why would anyone do this manual switching whatever it means just so that the SDU can respond to the satellite’s hourly interrogation which was basically all that the SDU did. Perhaps u can share with us your theory on this switching? What did this people do to the various buses, why, who are they and so forth.

    11. Nothing was heard from the plane after 1.43am (1743 UTC). None of the plane’s communication systems revived. All that happened was the satellite kept up the hourly pinging as it was programed to do and an SDU from the plane responded to the pinging by emitting the standard “I am here’ signal.

  9. Alex, Gysbreght, Littlefoot — I don’t see much value in continuing this conversation. Alex has his beliefs, and it doesn’t look like anyone else is sharing them. Let’s all agree to disagree.
    I want everyone to be able to express their point of view. But when people express their point of view too much, it can ruin the atmosphere and actually stifle the free flow of ideas. So let’s call this issue closed.

  10. Jeff,

    Your blog, your call, and you know best/most about it. Can’t speak for anyone else, but was following the debate between Alex and the others enthusiastically and with interest. Disappointed to see it shut down.


  11. Jeff – Thank you for stepping in. I was about to suggest they share e-mail addresses and conduct their respective theories privately and then post their conclusions.

    I would also like to suggest that the people who post here should try to be consistent in the use of certain terms such as events during the flight are given in UTC, the underwater pings are called “acoustic pings” and the “ping” transmissions between the satellite and aircraft are called “handshake requests” or something similar. The same goes for distances and speed. Perhaps posters could standardize on Nautical Miles and Knots? Using consistent units should make it easier for observers to understand the discussions.

    As for the general search area, way back around March 13, a “senior Pentagon official” is quoted as saying, “We have an indication the plane went down in the Indian Ocean.” I think this means US surveillance has more information than they will release officially.

    Also, while I don’t have any more information than the general public, I rather doubt that , like the person who lost his keys a block away but looks for them under the lamppost because the light is better, the ATSB chose to search closer to Perth for its convenience. At the time of the northeast move, there was much information being discussed regarding fuel burn, altitude and range. I believe moving the search area to the northeast was the best estimate of the parties involved.

    Regarding minimizing weight, I was told years ago that the little bottles of spirits sold onboard were changed from glass to plastic just to reduce weight. That doesn’t appear to be much of a saving but I guess it adds up.

  12. Great idea about the standardized units and terms, Lauren. As for the statement by the “senior Pentagon official,” I believe that at the time the Malaysian military had revealed the radar track over the Malay Peninsula, but Inmarsat had not yet disclosed its information on the pings (excuse me, handshakes!) so searchers were looking for debris north of Aceh.

  13. @JeffWise

    Yes, and if we go very early on March 8/9 we have this report……..

    The most recent information available is that at about 3:15pm (Australian EST) reports were made by Vietnamese authorities that a signal had been detected from the missing aircraft from 120 nautical miles southwest of Vietnam’s southernmost Ca Mau province. Shortly thereafter, at 4:10pm (Australian EST) reports were received from Vietnamese media and the NAVY that it had radar reports which indicate that the aircraft crashed into the sea, close to Tho Chu Island.

  14. Lauren: I recall looking into the timeline regarding this same reference by the Pentagon, later confirmed by the White House press secretary in a Q&A following a briefing. The analysis revealed no advanced or proprietary knowledge of the aircraft going down in the SIO by US intelligence assets. In fact, if I recall correctly, the reference was actually to recovery efforts focused then on the Indian Ocean in the vicinity of the Straights of Malacca. In short, I did not find any ‘smoking gun,’ while I did discover how closely several members of the Inmarsat board (owners of a radio spectrum consultancy based blocks from the Pentagon) work with the Pentagon and Homeland Security in a tight mix of policy and business regarding satellite communications security. It was quite interesting to witness how things work, actually, with private sector and government officials intertwined like lovelorn smack addicts, hunched over the same pile of good dope. I posted my findings, complete with names and addresses, here, back in April, I believe it was.

    And hello, everyone. We are all now moved into a nice new house in Tokyo in a quiet neighborhood, while I am now in the noise and scintillating clutter of Shanghai, grinding away. It’s good to be back – and no, I won’t be trotting out my old standby theory!

    That said, I am ‘happy’ to see a bit more meat on the bones of the ‘transition period’ between the two phases the flight in the hour or so post 18:25 – and that’s UTC, baby. And so does our flight that was not diverted due to a mechanical failure somehow mysteriously end, pilotless, transitioning from this diversion to that demise…some of us told you so, back when the only time figure we seemingly had for the transition was 18:22.

    Why and how was power restored to the left AC bus if not to fire up the SDU and attempt to communicate?

    All flights push back and take off – or are diverted – with a destination in mind…

  15. Lauren: well said re: standard terminology, and taking verbosity off-line.

    Re: Pentagon statement, and “searching by the lamp-post”: for those who blindly MIStrust authority, no amount of evidence of misdirection is necessary; for those who blindly TRUST authority, no amount of evidence will ever be sufficient.

    I have tried to approach this as objectively as possible – and have concluded there is something extremely fishy about search leadership decisions over the past six months.

    If I concede to you that it is POSSIBLE that the search – despite its many (and ongoing) dramatic and perplexing shifts – COULD have been just a long series of honest errors, and the Pentagon announcement an informed best guess…

    Will you concede to me that it is POSSIBLE the search was directed to the SIO by the Pentagon – and later rushed NE by the ATSB – for reasons OTHER than an honest effort to find MH370?

    Including (but by no means limited to): a desire to divert attention AWAY from sites in which US operatives were removing – and later (re?)planting – evidence?

  16. Jeff – read your Independent Group’s Sept. 9 report with keen interest. I’m sure I speak for many in expressing my gratitude to experts willing to help passengers’ families get to the truth.

    Re: Section 2.4: Aircraft Performance Limitation: a critical input driving your conclusions is a graphical representation of the ATSB’s performance limit, which, as you note, was presented with zero supporting documentation in their June 26 report. Your report goes on to base feasibility statements on the assumed validity of this arc. Did your group perform any independent VALIDATION of this arc, before using it to drive conclusions?

    If so, can we get access to this work?

    If not, why not?

    Finally: isn’t this performance limit circa June 26 – and isn’t a performance limit highly sensitive to the assumed southern turn point? If the ATSB has just recently decided the likely southward turn point was SOONER than previously thought, would that not necessarily force a significant redrawing of this arc?

    Wouldn’t such an update logically rotate this limit’s oval(ish) shape (whose foci would both point at and be a set distance from the assumed 18:40 cross-point) SW around the Inmarsat arcs? Wouldn’t this necessarily invalidate your “compression scenario”?

    Thanks in advance.

  17. Good question, Brock. The short answer is that we don’t know how that arc was calculated, we just took it at face value. Trying to sort that out would be a whole ‘nother kettle of fish–if you feel like volunteering, step up! My presumption is that it represents the very furthest that the plane could conceivably fly from its last observed location, given optimal airspeed, altitude, performance, etc.

  18. Lauren – regarding the use of plastic instead of glass to save weight on planes. For sure, Australian cricket teams on tour taditionally have drinking competitions and the sheer weight of their appetites would crash most aircraft. The now retired right hand batsman David Boon, did verifiably consume 48 cans of beer en-route to England for the 1985 series. This eclipsed the mark of 45 set by Rodney Marsh more than a decade earlier – and that was just two people!! And just glancing now at the 30 can block of “Emu Bitter” cans sitting not 20 feet away I can attest it was a streamlined exercize to get it out of the car and into the house, compared to glass, so I’m sure your example is valid.

    My quibble over weight was that if thee was a safety angle to having a back up battery in the SDU there would be one. But…..I think we are done there lol.

    Rand – I missed your prose. “lovelorn smack addicts.” Ah yes.

  19. Brock – my view would be that the search is so riddled with assumptions, some of them foundational ones, that the whole thing could be jerked one way or the other depending on what side of the bed Martin Dolan found his slippers.

  20. Lauren – “We have an indication the plane went down in the Indian Ocean.”

    I’ve pondered that as well and it’s ambiguous. Coming from a spokesman it could mean that we have no radar evidence for the northern route and the plane has gone.

  21. On reflection, I was guilty as charged, of hogging the microphone, and for that I apologize to everyone.

    On the topic of early reports, the Malaysians issued their first statement on MH370’s disappearance at 7.24am (23:24 UTC). The last transmission from the plane came in at 8.19am (00:19 UTC). Six minutes before that at 8.13am (00:13 UTC), the US 7th Fleet issued the following statement:

    “USS Pinkcney (DDG91), an Arleigh Burke-class guided-missile destroyer, is en route to the southern coast of Vietnam to aid in the search efforts of the missing Malaysia Airlines flight Mh370, March 8. Pinckney was conducting training and maritime security operations in international waters of the South China Sea. The ship could be in the vicinity of the missing jet within 24 hours…..”.

    2 days later on March 10th, the US 7th Fleet issued another statement that USS Kidd had also been diverted to search for the missing plane and that “…[USS] Kidd, like Pinckney, was conducting training and maritime security operations in international waters in the South China Sea before being sent to assist in the search efforts….”.

    The New York Times in its March 11th edition reported on a telephone interview with the spokesman for the 7th Fleet, Cmdr. William Marks:

    “Q. How difficult is this search and rescue effort?

    A. …… It’s very challenging. Look at the geography. At first we thought it was closer to Vietnam, just off the coast of Vietnam……… And….. I’m now hearing reports that the plane may have turned around. So we are now looking at this area in the northern part of the Straits of Malacca, in case it turned around……..”.

  22. A further extract from the phone interview with Cmdr William Marks:

    ” Q. How much longer could the search last?

    A. The way that we in the Navy look at this is that for the first 72 hours, we consider it still a search mission for survivors. Survivors have been known to make it at least that long, so from our perspective, we still hold out a little bit of optimism for survivors. That’s for that first 72 hour period. After that, it’s at the decision of the Malaysian government what they want us to do, and where they want us to be”.

  23. (1 of 2)

    Thanks, Jeff; I’ve been trying to “step up” since April.

    The ATSB’s performance limit is a line connecting the end of a series of hypothetical flight paths, varied over a range of possible (constant) speeds, each as straight as the Inmarsat pings allow. To hit all arcs on cue, the slower paths “fan out” to the East, and curl more tightly. On March 17, the ATSB chose the two straightest = fastest = westernmost two of these paths as their best guess. I’d bet these were around 470 and 490kts, and bore a striking resemblance to the mid-March NTSB “highest probability paths”.

    On March 28, the ATSB announced they were moving the search 600nmi NE. The sole reason given: “less available fuel”.

    What happens when you take fuel away from a performance limit? Each of the generating paths must contract back into itself in proportion to its total length (i.e. shorten all by x%). Their heading cannot change: speed and bearing are fixed by the Inmarsat arcs.

    With this fact, I was able to prove that (referring to fig 3, page 5 of the ATSB’s June 26 report) NO amount of fuel reduction could POSSIBLY have rendered the March 28 site IN, yet the March 17 site OUT. Yet away they moved.

    (In his August 20 response to my July 17 query, Martin Dolan admitted that the move was in fact DESPITE, not BECAUSE OF, the “less available fuel” assumption update. He admitted this because it is a stone-cold geometric proof. Yet to this day, the “BECAUSE OF” argument stands, uncorrected, as the explanation of record on page 6 of the June 26 report. Curious.)

    Short of introducing erratic flight paths, the only other ways to affect this performance limit are by a) adding wind effects (minor), and b) changing the point at which MH370 is assumed to hit the 19:40 ping ring. As veteran MH370 modelers already know, the key input driving where models put MH370 on the 00:19 arc is where the models have it by the 19:40 arc: if your model hits the 19:40 arc 4 degrees (“angle around the ping ring”, NOT a coordinate) clockwise of your buddy’s model, your end-point (ignoring wind) will be the same 4 degrees clockwise on the 00:19 arc. (I visualize “turning the arc dial” in Google Earth).

    Same thing for a performance limit: if you move your assumed 19:40 entry point 4 degrees clockwise, the performance limit rotates around the arcs by the same 4 degrees.

    Interestingly, the original ATSB performance limit (SE border of S1/S2/S3, Fig 3, page 5, June 26 report) validates remarkably well against a paper I found online (Delgado/Prats) which studied the impact on fuel flow of systematically varied cruising speeds for large commercial aircraft. I extracted values from Fig 6 (page 8) of this paper, and found that, if I calibrated its relative performance to ONE point on the ATSB’s arc, I essentially replicated the ENTIRE arc. Interesting.

  24. On April 1, they moved the search an ADDITIONAL 750nmi NE (total move in four days: 1350nmi; the distance from Cleveland to Haiti), and stayed for 2 months. The only way one could move the end point THAT far NE and still fly FAST enough to last six hours is if you assume MH370 circled NW of Sumatra for nearly an HOUR (a circuity some readers will find familiar).

    But a quick inspection of the charts accompanying the Preliminary Report (published May 1) clearly shows no such loitering. Instead, they reach s20 by slowing the plane down to 323ktas for the southward leg. Too slow, according to my model. And according to THEIR model – because it matches. In fact, I DEFY a pilot to simulate the May 1 published flight path, and not run out of fuel.

    “But Brock,” I can hear you patiently explain to me, “perhaps they DID know of circling prior to 19:40? Maybe it’s sensitive information, whose release their source forbids.” Fair enough. But then why have they now abandoned that site, in favour of a flight path that heads straight south, and leaves NO TIME TO HESITATE near Sumatra? You can’t have it both ways: if ATSB data was AHEAD of us, their RATIONALE would be dodgy/shifty, but NOT their CHOSEN LOCATION. Once their search site is abandoned, so must all claims to secret info the ATSB “must have had”.

    Ergo, the ATSB has not been straight with us. Ergo, the petition to force disclosure.

    Applying the “rotation” method to the question I asked you today, Jeff: because BOTH the search epicentre AND the performance limit anchor to the same 19:40 ping ring intersection point, the distance each should move along the 7th arc in response to a change in the “turn south” point is IDENTICAL. So if the ATSB ever shows us how far their best-estimate flight path has moved clockwise – in rotational degrees along ANY Inmarsat arc – we’ll know how many degrees to rotate your (screenshot of the ATSB’s June 26) performance limit.


    Delgado/Prats fuel flow study (presented to Conference on Air Traffic Management Economics, Belgrade, 2009):

    Geometric proof that the March 28 search move was incompatible with the reason given:

    Confirmation by Martin Dolan that the official reason given by the ATSB for moving the search was bogus:

  25. @Rand,
    Welcome back!
    I thought we had lost you for good! Without you the number of of my unnecessary commas rises sky high!

  26. @Brock, thank you for reminding us of and dismembering the ‘less fuel’ argument. I said back then that it didn’t make any sense to me, but I didn’t back it up with your cristal clear arguments. And I was more trusting than nowadays, that the authorities might know more than they choose to disclose publicly. Which might actually be true, but I’m not convinced anymore that -if there is additional knowledge – is will be used and eventually lead to the discovery of the plane’s ultimate fate…

  27. Brock/Littlefoot – Inmarsat are careful to describe themself as technical contributors, and only one of a bunch. I don’t buy it and I feel that ATSB are taking bullets for them at the moment. Inmarsat are the main drivers back there I believe and they have performed major revisions of their work at a number of intervals and each time the search moves dramatically. The fact that they have been allowed, even ostensibly to run the show has had me wondering often if we are even watching the main event. They own the satellites and have by far the best technical visibility of the whole apparatus, and they divulged to a level of their choosing. No Inmarsat, no search. I picture them as occupying a special place in the tent.

  28. To be able to fully analyse the BFO and BTO data, one needs:

    1. Advanced training in mathematics

    2. Thorough knowledge of the AES, GES and satellite concerned

    3. Historical data from the AES, GES and satellite involved as well as historical and after the fact data from other AESs, GESs and satellites for comparison.

    Only people from Inmarsat are in a position to analyse the data. The typical accident investigator, someone like John Goglia, would not know where to begin analysing such data.

  29. RE Aircraft performance limits:

    “The assumptions made for the performance calculations were the following:
     The aircraft was flown at a constant altitude
     The speed selected was operationally achievable for the given altitude

    A slightly longer range would have been calculated if, as the airplane became lighter as it consumed fuel, the altitude had been allowed to increase with a corresponding decrease of groundspeed for optimum range performance. Switching off the airconditioning packs would also help.

  30. Rand – welcome back! And glad to hear the move to Tokyo went well.

    Brock – Keep it coming!

    Matty – +100 your last comment


    There’s been so much focus on the (unanswered) SAT phone call from MAS to MH370. But is it possible that there were outbound SAT calls made from the plane as well?

    EVERY business-class seat on MH370 came equipped with a SAT phone. Days after I tweeted about this, MAS removed mention of this fact from their website:

    But the deleted page can be found on

    Why would MAS delete this information from its website?

  31. Gysbrecht: certainly, the length of each line must take [decreasing weight as fuel is expended] into account.

    I translate this into the statement: “If you take away x% of your fuel, range drops y%”, where y<x, due to the lighter plane.

    However, the thing that matters (to MY key point, anyway) is that neither x NOR y vary across the set of perfomance line-generating paths. If you take x% of the fuel away, ALL paths must contract by the SAME y% – so the heart of my argument (already conceded by Mr. Dolan) is unaffected.

  32. Matty: re: Inmarsat: agreed. But ATSB has to be the first domino. If we can get investigative journalists to pull the pickle out, and force accountability for all past decisions, the ATSB will give up their puppeteers. My guess is that they are ACHING to do this.

    My guess is also that the puppet strings do not terminate at Inmarsat.

  33. For those reflecting on verbosity, I’ll offer my own solution, from my own similar experiences:

    Try commenting from an iPhone. Exclusively. The small window and “cost” of each keystroke will quickly sharpen your ability to be concise.

    Completely serious here. My A’s in writing class came not from a computer, but from a barstool using an iPhone. Let’s see if it still works:

    Back on topic, one of the “revised” search areas contained an odd sequence of high, low and medium priority search areas, in that order. That order necessarily requires some outside variable, or a very strange hook in the fuel burn curve.

    Geometrically, I was able to show that this was likely due to the existence of TWO search area circles, maybe 50km across and 100km apart.

    These little circles were centered at the intersection points of two very large circles. The line between the centers of the large circles bisects, and runs perpendicular to the line between the small circles. Think of an elongated diamond or cross with circles on the obtuse vertices.

    The long axis line can be extended indefinitely, and eventually hits Cocos-Keeling and I believe DG. The implication was that the two large circles represented an acoustic or seismic signal picked up by only two stations, and because triangulation could not offer less than 2 solutions, the result was these two little circles which fell near the 7th ring.

    The two little circles are not equidistant from the 7th ring, however. The nearer of the two determined the high priority area, and the farther one determined the medium priority area. The center of the cross or diamond was excluded by triangulation and therefore the area on the ping ring nearest to it became the low priority area.

    So it is my belief that at least one search area revision had nothing to do with fuel but with some other signal that a radius could be derived from, picked up in two distant places at slightly different times.

  34. JS: whatever the reason (ATSB claims WAYPOINTS reddened it), my point is that the red zone was infeasible, performance-wise.

    I don’t care what your map says are well-worn flight corridors. Or what your detectors detected – before OR after driving in the red zone stakes. If the plane lacked the fuel to reach it, the plane lacked the fuel to reach it.

  35. Today I’ve received a reply from the Australian Defence Force re: my request for the reasons for not releasing the recordings of the putative acoustic pings.

    ADF has referred my communication to the JACC. When, (if) they respond, I will post it.

  36. Nihonmama,

    Hi there again. Good question about the apparent lack of satellite phone calls from the passengers or crew of MH370. has a description of the business class cabin facilities of Malaysia Airlines that matches the description given in your link but a bit more detailed:


    Fold out your personal 10.4 inch LCD touchscreen monitor and choose from the same level of entertainment options as First Class passengers. The SELECT plus entertainment system allows you to browse through the movie and CD library, leaving you in control of your own personal entertainment program from the comfort of your seat.

    Catch up on work and power your laptop through the 115 volt power outlet that accepts multiple plug types. You even have access to email and livetext on your monitor and the use of a satellite telephone, so you never need to be out of touch from business or loved ones.”

    So business class passengers on MH370 could send emails, text messages and also make phone calls using the satellite phone.

    Page 22 of the ATSB Report dated June 26th states:

    “Approximately 90 seconds after the 1825 log-on request, communications from the IFE ( In Flight Entertainment) system on the aircraft were recorded in the SATCOM log. Similar messages would be expected after the 00:19 logon request, however none were received”.

    These ‘IFE communications’ must be the transmissions at 18:27:03 [Eleven Octet User Data] and 18:27:04 [Four Octet user data].

    The question is did someone use the IFE system, say to send a text message, coincidentally right after the SDU logged back on at 18:25 or was this message already in the system, in the queue so to speak, when the SATCOM system lost its link to the satellite sometime after 1707. In this regard, below is an extract from the ACARS report from Swiss Air Flight 111 which crashed due to a fire, where the SDU was also from Honeywell and the satellite used was one of Inmarsat’s although for that flight, VHF datalink (from ARINC) was also utilised:

    “…The ARINC audit data showed the internal message counter in the CMU was at M63A when communications coverage was lost. When the coverage resumed with ARINC, the CMU message counter was at M66A, which indicates two messages were generated but not received by ARINC. If these messages were generated by the crew they would have remained in a message queue until they could be delivered….”.

    If the message on 18:27 had been generated only at 18:27 or just before, it would suggest the plane was still in the air or at least had not crashed by then. In that scenario, one would expect further IFE messages to have been generated and transmitted in that subsequent 6 hour period, but as the ATSB report noted, ‘none were received’ subsequently.

  37. @Alex,

    If I understand you correctly, you claim the single message had to be placed in the queue well before 18:27 but after 17:07 and also had to have been the last and only message having been put into that queue.

    This would indicate that placement of this message into the queue and the loss of the data link would be likely correlated and possibly simultaneous. E.g. whatever emergency happened, stopped the successful transmission of the message in progress and also stopped anything/anyone else from creating any further messages.

    That would indeed point to an “all lights out” scenario in that window of time and possibly sometime very early in that window.

    That begs the question, how is a controlled flight (turn back, turn NW in Malacca St, turn South after that, etc) possible?

    That in turn begs the question of how reliably do we know that the radar track is that of MH370? (You may see, where I am going with this…)

    I have it from a reliable source, that ATSB are confident that last radar detection at 18:22 was indeed that of MH370. But I am worried that ATSB has had high confidence in apparent facts previously. Confidence, which turned out to be ill-founded later.

    I have previously posted a link to Ron Black’s blog about his Two Planes Theory. His motivation for doubt on the radar track is that sharp corner in the track shortly after 17:22. Ron has recently included a 67° banking angle turn radius in his blog, which he states would be at or near the structural performance limit of the plane.

    I have updated my CAD overlay with this new radius and it appears that even this extreme turn radius would not account for the sharp corner in the radar track.

    Updated Overlay:

    Calculations (lat/lon grid to drawing scale):

    Ron’s blog post (original location):
    (and a new location):

    The same reliable source as mentioned above states that ATSB explain the sharp corner by possibly being an artifact of grafting several radar tracks together. Clarification of that, and the radar trace resolution around the track have been asked of ATSB, but I have not seen any further info on it yet.



  38. @Brock – agreed. My point was that one of the maps was driven by what appeared to be acoustic measurements, not fuel. It was an attempt to force a match between two sets of data, one of which could not be reconciled with the flight path.

    @Alex – very interesting about the IFE. Briefly, what do you know about this message counter? It’s not hex. Is it base-36 or just M##A for each trip?

  39. @JS,

    I do not know the answer to your question. The ACARS report for Swiss Air Flight 111 can be found online. In the data log section of that report, the contents of each transmitted message were described. As we all know, Inmarsat have so far refused to disclose 19 of the 28 fields of data including the ‘SU Contents’ of each transmission, let alone provide a description of each of the messages.

    You may remember our conversation on the TMF Blog about why the SDU requested to be logged on at that particular time 18:25 UTC. According to pages 17/18 of the ATSB Report, “…if the ground station has not heard from the aircraft within an hour, it will check that the connection is still operational by transmitting a ‘Log on Interrogation’ message on the P channel using the aircraft’s unique identifier. If the aircraft receives its unique identifier, it returns a short message on the R channel that it is still logged onto the network….”. According to the 47 page data log, the last transmission from MH370 was at 1707 UTC. So the satellite should have started pinging around 1807 UTC (plus or minus 4 minutes according to Don, which one hour 4 minute gap was seen in the case for Siwss Air 111), assuming it is true that the last transmission was at 1707 UTC. If there was no response, the satellite would declare the aircraft ‘logged off’; see the last entry for the data log for Swiss Air 111. However, we do not see any such ‘Log on Interrogation’ from 1707 UTC to 1825 UTC for MH370. Instead we see a Log On Request at 1825 UTC.

    What would a terminal do if the connection has been lost for whatever reason and some time later the satellite sends a Log On Interrogation? Common sense suggests 2 possibilities. Either the terminal fails to react and the satellite ends up declaring the terminal as ‘logged off’ ( as what happened in Swiss Air 111 and for MH370 at 0019 UTC) or the terminal reacts by attempting to regain the connection, by way of sending a Log On Request.

  40. @JS,

    I omitted to mention that the last transmission from MH370 was at 00.19 UTC and the last Log On Interrogation from the satellite was at 01.15 UTC which is one hour minus 4 minutes. So Don is correct in his understanding of this plus or minus 4 minute thing.

    Assuming it was a Log on Interrogation which prompted the Log On Request at 1825 UTC, working backwards, a one hour plus 4 minute gap works out to 1721 UTC as the last SATCOM transmission from MH370. 1721 UTC also happens to be the time the ADS-B and SSR transponders last transmitted their respective signals. We do not know if the last few SSR signals were abnormal in any way, but the last couple of ADS-B signals did show some abnormal data indicating that the precipitating event could have taken several seconds to play out. The 1721 UTC SATCOM transmission if it did happen, may have been a ‘fault transmission’ triggered reflexively within the system or a transmission attempted by a passenger or crew reacting to the precipitating event unfolding.

    Think I have used up my quota for the day. Will be back tomorrow to answer any questions.

  41. @MuOne,

    Sorry I did not see your message earlier. I will post a comment on this radar issue tomorrow. I had previously posted several comments on this issue on the TMF Blog (in the last 2 threads on MH370), perhaps u can check them out, in the meantime.

  42. @Brock – I guess I’m more of the trusting type. Is it possible that the search was diverted to the NE for reason(s) other than an honest mistake? Anything is possible but I cannot imagine a scenario that would justify such a costly diversion. However, I believe that the plane could not have hit the 19:41 BTO Ring and then reached acoustic ping search area without making additional turns.

    It seems most theories are based on a straight flight path with either zero, one or two turns before turning south after being in the area of NILAM at 18:22. I think many of the theorists cannot accept that anyone was conscious after 19:41 but, I do not see any reason why multiple turns could not have been made both before and after first heading south. For example, NIXUL waypoint could have been dialed in with the Cocos Island’s waypoint (YPCC) after NIXUL. Without any waypoint entered after YPCC, the plane would continue on the same magnetic heading. The only problem with adding the extra turns is it would increase the search area.

    @Matty – The quote from March 12 was not from a spokesman but a “senior Pentagon official.” However, as Rand pointed out, the White House announced that the US did not have “advanced or proprietary knowledge of the aircraft going down in the SIO.” I’ve checked further and it appear that the USS Kidd was directed to an area where the Andaman Sea meets the Indian Ocean around that time. I’m not sure exactly when the SIO was first considered but I think it was around the time that the Northern and Southern tracks were first revealed. All of this just means that my implication that US Intelligence had an indication of the plane going down in the SIO is incorrect.

  43. I was very impressed with Richard’ spreadsheet that evaluated the BTO & BFO data but sometimes, we engineers try to simplify the math when revaluating lots of data. Here is my simplified evaluation of the data (excluding BFO since since they are too complicated for me) with a few assumptions.

    The initial fuel load was about 109,000 lb. Let’s say the plane turned south and passed NOPEK at 18:40 and had burned 34,000 lb of fuel by 18:40. The increased burn rate extra fuel burned during taxi, take-off, and maneuvering. From NOPEK on, it flew a straight line (i.e., no turns). Let’s say fuel exhaustion occurred around 00:15 (after the 00:11 handshake but a few minutes before the 00:19 assumed re-boot). That means it burned 75,000 lb. of fuel over 5.5833 hours or 13,400 lb/hr. At this burn rate, the published performance table for a Boing 777-200 with RR engines shows a speed of 385 kts at FL200 or about 455 kts at FL300. For added simplicity, I’m saying air speed equals ground speed. Starting at NOPEK at 385 kts for 5.5833 hours you’ll get a point near the 00:19 handshake ring on a track that never touches the 19:40 ring, so that speed is eliminated. Also, this point is well southwest of the acoustic ping search area so I think Brock is correct to challenge this end-March/early April move.
    The only way to touch the 19:40 ring and get to the same point would be to add turns or have it fly faster. At 510 kts, the track does not hit the rings at the correct time. At 455 kts, the track hits all of the rings at the correct times and ends within 20 NM of Duncan Steel’s Independent Group’s Sept. 9 location of S37.5, E89.2 and also agrees with the ATSB graphic that Brock posted at 11:55 PM on Sept. 10. Simplified math – same answer.

    As Brock pointed out, if you change any of the assumptions, you just slide up or down the 7th Ring.

  44. Lauren: while I admire those whose capacity to trust is as expansive as yours, I am much more skeptical.

    The move from s40 to s20 would have SAVED millions of dollars: it brought the search 4 times closer to port during its most expensive 2 months.

    Other possible motives are as I outlined (i.e. to VACATE an area, under orders, for whatever sensitive reason). We won’t know the reason WHY they chose an infeasible location until they tell us.

    And they won’t tell us until we ask.

    Forcefully enough to command their attention.

  45. MuOne,

    The purported turn west is at the heart of Inmarsat/the authorities’ theory that MH370 had flown on for 7 hours after its disappearance, to ultimately end up in the South Indian Ocean. The plane disappeared from radar at 1.30am (1730 UTC) over the South China Sea. The ping rings for all but the 6th and 7th arcs, are to the west of the South China Sea. According to the authorities, the plane was somewhere on the first ping ring at around 1825 UTC, so for the theory to make sense, MH370 must have traveled west from 1.30am (1730 UTC) to hit the first ping ring at 2.25am (1825 UTC).

    So if the evidence shows that MH370 did not turn west during that period of time or for that matter at any time, this theory of a 7 hour flight to oblivion ending somewhere in the middle of the South Indian Ocean, would become untenable.

    To be able to evaluate the evidence or the lack thereof of this purported west turn, one needs to know how radar works and what sort of radar was out there covering the areas that MH370 must have traversed, if indeed it had turned west.

    We all know by now there are 2 types of radar used to monitor airplanes. Primary radar where the radar equipment sends radio waves out there which radio waves would bounce off any object in the sky and gets deflected back to the radar and secondary radar where the radar equipment sends a signal to the plane and a transponder on the plane responds with a coded signal identifying the plane which gets transmitted back to the secondary radar equipment. An extract from Wall Street Journal on March 13th:

    “… As is standard international practice, Malaysian controllers use two radar systems, a primary and a secondary, to monitor their airspace. The primary radar is a so called noncooperative system that tracks objects from the ground without identifying them, regardless of whether they wish to be tracked. The secondary radar is a cooperative system: It works by sending a message from the ground that asks the aircraft to identify itself; a transponder from the plane then sends a code that gives its identity, speed and altitude. The primary system supplies range, bearing and position…”.

    Where would all these radars generally be located?

    There would be 2 main locations, at or around airports on the civilian side and at air force bases on the military side. Thus typically at each airport there would be both a primary radar of limited range usually around 60 NM called terminal approach radar or TRACON and a secondary radar usually with a range of around 200 to 220 NM, co-mounted together. For the air force bases, there would usually only be a primary radar usually referred to as en route radar, of much longer range, typically 200 to 240 NM. The radars at these military bases have a dual military civilian/ATC function.

    The returns from all these radars get piped down to the main air traffic control centers in the country. For Peninsular Malaysia, the main ATC center is located at Subang (a suburb in KL). The screens at Subang ATC would reflect the ‘integrated’ returns from all these radars ie primary TRACON radars and secondary radars from the various airports and long range en route radars from the various air force bases.

    Duncan in his last post on his blog has set out the locations and respective range of the air force radars covering the relevant airspace of 3 countries, Malaysia, Thailand and Indonesia. Don Thompson has done a paper specifically on the various air force radars and operation centers in Malaysia.

    The text of the Preliminary Report, dated April 9th but released on May 1st, does not contain any detail of this purported turn west other than to say the following:

    “A playback of a recording from military primary radar revealed that an aircraft with a possibility of MH370 had made an air-turn back onto a Westerly heading crossing Peninsular Malaysia. The search area was then extended to the Straits of Malacca”.

    The ATSB Report dated June 26th, has a diagram, Figure 2 at page 3, showing the purported turn west.

    To be continued…..

  46. Figure 2 of the ATSB Report contains a purported radar track of MH370 from 1722 UTC to 1822 UTC. However, this was not the route first mentioned by the Malaysian military or the Thailand military. The route first mentioned by the Malaysian military was an air turn back ie reciprocal heading back to KL and then a turn somewhere with the blip last seen over Pulau Perak at 2.40am. Likewise the Thailand military, 10 days after the plane’s disappearance on March 18th, mentioned a blip heading back to KL. The Malaysians later changed their story to a purported flight following waypoints GIVAL, IGREX etc. The times where the blip was supposedly seen at certain points on the ever changing routes also changed; eg what was 2.40am (1840 UTC)initially over Pulau Perak changed to a time of 2.03am (1803 UTC) and what was 2.15am (1815 UTC) at MEKAR became 2.22am or 1822 UTC.

    Whether the route was as set out in the ATSB Report or as mentioned in the many permutations prior, MH370 if it had turned westwards and crossed Peninsular Malaysia, would have been seen on the following radars:

    1. The military radars of Peninsular Malaysia at Gong Kedak over on the north east coast, at Penang/Butterworth over the northwest coast and at Bukit Ibam on the mid-east coast .

    2. The military radars of southern Vietnam including at Ca Mau peninsula .

    3. The military radars of southern Thailand, including at Hat Yai (Khok Muang) and Phuket .

    4. The military radars of northern Sumatra, Indonesia at Lhokseumawe and Sabang.

    5. The primary TRACON radar of the airports in northern Peninsular Malaysia and in particular the airport at Kota Bahru and the airport at Penang.

    6. The weather radar of all the civilian planes flying in the vicinity of MH370 in that period of time.

    7. The radar of all the military planes flying within range of MH370.

    8. The radar of all the military ships in the South China Sea and in the Straits of Malacca within range; USS Pinckney and USS Kidd with their highly sophisticated AEGIS radar were both at the South China Sea.

    9. The ATC Center for Peninsular Malaysia at Subang/KL which would have returns from all civilian and military radars in the country.

    10. Likewise, the ATC Center for Thailand at Bangkok.

    11. Likewise, the ATC Center for southern Vietnam at Saigon aka Ho Chi Minh City

    12. Likewise, the ATC Center for Sumatra, Indonesia.

    13. The air force operation centers for Malaysia at KL and Kuantan which would have the same information/radar returns from all radars both primary and secondary, just like the ATC Center.

    14. Likewise, the air force centers of the other neighbouring countries.

    Only 2 radar stations reported seeing a blip that was ‘possibly’ MH370, the one at Butterworth and the one at Surat Thani, Thailand. Critically, none of the ATCs or air force operation centers reported seeing anything that could have been MH370.

    I will, tomorrow, analyze what was observed on the radar at Butterworth and on the radar at Surat Thani.

  47. Please see Jeff’s latest article comment section for my response to the IG’s latest update.

    Anyone desiring a PDF copy can e-mail your request to the address in the paper.

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