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. @Littlefoot-Matty-Brock

    I’m a bit taken aback that a simulation flight hasn’t taken place {Maybe after the third year of the search) while trying to match the BTO BFO data along the way of understanding the greatest mystery of our modern time. Everyone knows it’s a logical step. Forensically it’s the logical step….why wait?

  2. What could be the reason for this tale of 2 halves?

    For an answer, I will quote from the comments from VictorI and Don posted on Duncan’s blog back in April.

    VictorI:”….. For those trying to decipher the BFO graph, here is my current thinking: 1. For the early ping times, before the course change of the plane, I believe the SATCOM module was applying the offset correction algorithm to compensate for the L-Band shift and the BFO graph represents the residual from applying an imperfect offset (plus the C Band shift). I believe this because the data shows that some offset correction was applied to lower the net frequency shift. 2. For the later ping time (18:29 UTC and later) I do not believe any offset correction is applied by the SATCOM module. The residuals are too high implying a very inaccurate offset correction algorithm. I think Inmarsat would do better…. 4. Why would the offset correction not be applied at the later times but applied at the earlier times? To provide an answer, i attempted to find what common element might turn off ACARS while also turn off this offset correction. 5. After some research, I found that there is a Communications Core Processor Module in the Aircraft Information Management System (AIMS) in the electronic bay. Removal of this card….. would disable ACARS and also prevent the SATCOM from getting updates of speed and position from the AIMS….”

    Don: “…. Victor: that’s a very plausible thought and even, more simply, just breaking the interconnects between the AIMS modules in the main equipment center and the satellite data unit (SDU) located in an overhead equipment bay toward the rear of the cabin would have the same effect…… However, can it be assumed that the SDU would continue to maintain its datalink to the GES with only power applied?”

    VictorI:”…. This is far from my area of expertise (of course that has not stopped me before) but I would think that the SATCOM unit would respond to an interrogation from the satellite as long as power were applied. My theory is based on a broken data path between the AIMS and the SATCOM. I arrived at this theory by trying to understand/reconcile the BFO graph. A damaged and disconnected cable would have the same effect as a pulled card…. I would agree that any disruption of the data path between the AIMS and the SATCOM would have the effect of disabling or degrading the offset correction and also disable ACARS.”

    A lightning strike which managed to penetrate into the aircraft would have fried all the cables/wires and caused a total electrical failure, resulting, among other things, a broken data path between the AIMS at the front and the SDUs at the back.

  3. Brock,

    I have over on the TMF blog, articulated some thoughts regarding what appears to be a cover up on the part of certain governments and the various aviation authorities. See for eg my comments addressed to Bruce Lamon on August 23, 2014 at 8:49pm and on August 27, 2014 at 2:04 am, in the latest thread on MH370 on that blog entitled “New Statement re MH370”.

  4. Alex,

    RE the ‘lightning strike’ theory:

    I suggest you take a look at Tim Vasques’ site at :
    [quote]Wheather is not believed to be a factor and this is indeed the dry season for south-east asia …[/quote]
    The satellite IR images show no clouds in the area where the plane disappeared from ATC radar.
    Comment on the 2014-03-08 0000 UTC sounding for Kota Bahru, Malaysia:
    [quote]This is a fairly stable and benign sounding …[/quote]

    So where did the lightning come from?

    If a lighning strike managed to penetrate into the aircraft and ‘fried all the cables/wires’, caused a total electrical failure but the SDU somehow managed to continue functioning on its internal battery, why did it cease functioning sometime between 17:07:48 and 18:03:41, and become alive again with a log-on request at 18:25:27?

    RE your ‘tale of two halves’:

    The division is at sometime between 18:28 and 18:40. Before that time the BFO’s indicate the plane travelling North, after that time they indicate the plane travelling South until at least to the 5th ping arc.

  5. Chris Butler – Regarding a test flight, turns out that the satellite has moved, and is moving, so it was never an option! Comforting isn’t it?

    Littlefoot – I reposted some old but very interesting links of yours yesterday for any who haven’t seen them but I can’t see them anywhere, so here –

    Iranians on the plane.


  6. Alex: Yes, that was my theory back in April. But it was based on an incorrect understanding of the BFO. At that point, Inmarsat had not fully disclosed how the BFO was defined. I no longer believe those statements to be true.

  7. I think there is plenty of BTO/BFO data in the Inmarsat historic logs from flights where precise navigational data (eg GPS) is available to allow the algorithms to be verified. The problem they have is the precise bias calibration of that aircraft on that day, and the frequency offset induced in the satellite, which is variable with time and temperature (at least). Test flights would not help.

  8. Alex,

    RE YR BFO calculations yesterday at 10:48 PM:

    The following graph compares the measured BFO as recorded in Inmarsat’s communication log to the BFO that would have been obtained if the airplane had been stationary at the point where ATC radar lost it at 17:22 UTC.

  9. Gysbreght,

    1. The weather was reported to be good, no dispute about that. According to, they did not detect any thunderstorm in the region where MH370 had disappeared from. The weather maps/pictures collected by Tim Vasquez show only light clouds at the region around IGARI at the relevant time. According to the March 9th edition of The Guardian, a pilot who flew a similar route 12 hours earlier reported thunderstorms but nothing that commercial airliners could not handle. At 1.21am over at IGARI, MH370 was at an altitude of 35,000 ft. A pilot flying westbound to southern Vietnam confirmed the generally fine weather but critically, also reported seeing lightning ‘way off to the southwest’, which would be the area MH370 was flying through:

    ” We entered HCM FIR last night westbound at FL340, passing Moxon (the boundary with WSJC) at about 1720Z, transitted HCM and Phnom Penh and exited, passing overhead PNH at about 1810Z. We experienced no problem with VHF Comms with HCM Centre, and VVTS CPDLC/ADS also worked fine. We encountered no adverse wx – in fact it was a beautiful clear NE monsoon night, though there was some limted scattered lightning visible way off to the SW. 121.5 was congested, with both HCM Centre and another MH flight trying to contact MH370. HCM Centre were also making repeated attempts to contact the aircraft on the normal Centre frequency” [PPRUNE, March 8th, post #120].

    2. So generally clear or slightly cloudy skies at around IGARI but also some limited scattered lightning with thunderstorms earlier in the day and if lightning had struck MH370 at IGARI, it was a strike at high altitude. All of this points to positive lightning. From Wikipedia:

    “Unlike the far more common ‘negative lightning’ positive lightning originates from the top of the clouds…. A positive lightning bolt can strike….often in areas experiencing clear or only slightly cloudy skies, they are known as ‘bolts from the blue’ for this reason. Positive lightning typically makes up less than 5% of all lightning strikes…. Positive lightning bolts are considerably hotter and longer than negative lightning. A bolt of positive lightning may carry an electric current of 300 kA and the potential at the top of the cloud may exceed a billion volts- about 10 times that of negative lightning. During a positive lightning strike, huge quantities of extremely low frequency (ELF)and very low frequency (VLF) radio waves are generated. As a result of their greater power, as well as lack of warning, positive lightning strikes are considerably more dangerous. At the present time, aircraft are not designed to withstand such strikes since their existence was unknown at the time standards were set, and the dangers unappreciated until the destruction of a glider in 1999…. Positive lightning tends to occur more frequently…. in the dissipation stage of a thunderstorm…”.

    3. In the 1999 glider plane incident, the plane which was made of composite material, disintegrated in mid air after getting hit by positive lightning. The strike was measured at a power of 8 to 9 times of the prevailing threshold for aircraft lightning protection of 200,000A. This is what the AAIB had to say in its investigation report:

    “… CFRP [carbon fiber reinforced polymer] is an electrically conductive material, but is more resistive than aluminum alloy. Modern jet transport types are designed with increasing utilisation of such composite materials for structural and control surface elements. One example of this trend is the Boeing 777….. Recommendation No 99-49. It is recommended that the CAA should request serious consideration, during its participation in the current international review of aircraft lightning certification standards, of the fact that energy levels from positive polarity discharges have been shown to greatly exceed those specified in Advisory Circular AC20-53A, with the associated implications for the certificated lightning protection assurance of existing and future aircraft designs, particularly those which utilise significant amounts of composite material in their primary and control structures.”

    4. As set out in a previous comment, MH370 exhibited all the signs of having been hit by a lightning strike of high intensity: the instant and total electrical failure at 1.21am at IGARI, the electromagnetisation of its radio equipment with the difficulty in establishing radio contact and the static and interference heard by the pilots of MH88 when they finally got through to MH370 at just after 1.30am, the apparent dazed condition of the co-pilot of MH370 during that radio contact, the what appears to be St Elmo’s fire on MH370 observed by the Kiwi on the oil rig (momentary flames, object in one piece) and last but not least, the pilots of MH370 yelling on the SOS call at 1.43am that the cabin, which was made of composite, was disintegrating.

  10. Alex,

    RE Yr #1:

    On march 8 many rumours were floating on the internet, including that the plane had landed safely in China.

  11. Gysbreght,

    Thank you for the graph.

    Those would have been the BFO values IF the SDU was functioning normally. But we know the SDU was not functioning normally.

    1. U will note from my earlier comment addressed to Richard Cole, the SDU was out of whack during the period of the pings. The first BTO value was said to be off by 4600us. According to Inmarsat, it was supposed to be 12520 but instead we got 17120. An error of 37%.

    2. The second value should also be 12520 (if the first value of 12520 is correct), but the reading came out to be 51700. An error of more than 300%.

    3. The third value reads 12560. How do we know it is correct, since the first 2 values were off by so much? We just do not know.

    4. Likewise the BFOs in those 2 minutes went from 142 to 273 to 176. They cannot all be right and they may all be wrong.

    5. We have altogether 14 R channel readings post 1707 UTC. By Inmarsat’s own reckoning, 4 out of those 14 readings are way off. That is almost 30% of the readings.

    6. Then we know that Inmarsat’s explanation for why the readings were off, is just plain false. The first log on request when the plane was at KL did not have a ‘fixed offset’ of 4600us and the related LLA did not show any ‘variable delay’, in contrast to their post 1707 UTC equivalents.

    7. So, wrong readings, wrong by up to 37% for some and for others more than 300%, affecting 30% of the readings as a whole. Just what sort of system is this and why are people still giving credence to these post 1707 UTC numbers.

  12. @Alex

    “Just what sort of system is this and why are people still giving credence to these post 1707 UTC numbers.”

    Because right or wrong there is nothing else…at least in the public domain.

  13. “However, analysts had still not been able to pinpoint precisely where along that curve Flight 370 ended.

    “At one point we had them all more or less agreeing on the same area. We are now finding with the slight change in the assumptions about the data that we can’t get full agreement. So we are going to have possibly two areas of primary focus,” Mr Dolan said.”

  14. “We know that the aircraft is in the water or on the sea floor close to that arc, and we are doing everything we can – which is a lot – to make sure we find it there,” said Mr Dolan.

    They really don’t “KNOW” anything!

    It’s the height of arrogance!!

  15. Alex,

    Your ‘lightning’ theory needs to simply be put to rest. Enough! It is just downright absurd, and carries no merit, NONE.

    I implore you to put an end to this particular piece of pure fiction. It furthers nothing and is detrimental to the overall discussion that some are attempting to engage in. The families deserve better than this convoluting rubbish.

  16. Gysbregth,

    Sorry for the delay in getting back to u on the other question. I am in different time zone (morning here now).

    1. The last ACARS transmission was at 1707 UTC (1.07am).

    2. According to the authorities, the next ACARS transmission was scheduled for 30 minutes later or 1737 UTC. That transmission never materialised.

    3. So ACARS stopped some time between 1707 UTC and 1737 UTC. The evidence shows the plane suffered a total electrical failure at 1721 UTC. The inference can be made ACARS ceased at such time, as all other communication systems requiring electrical apparently did. (SSR, ADS-B, etc).

    4. The GES sent an uplink message at 1803 UTC. We have not been told what the message was about but people think it is some sort of wind or weather update.

    5. The fact that the GES attempted a message at 1803 UTC indicates that the MH370 SATCOM system was probably still logged on at such time.

    6. We know MH370 SATCOM system must have been logged off before 1825 UTC because at 1825 UTC there was a log on request from the system. So between 1803 UTC and 1825 UTC, the system logged off.

    7. The last transmission from MH370 (prior to such log off) according to Inmarsat data log, was at 1707 UTC (the second ACARS message).

    8. According to the authorities, the satellite is programed to ping the SATCOM terminal if the satellite/GES has not heard from the terminal after 1 hour.

    9. Don Thompson has done research showing that this 1 hour interval in practice may actually be plus or minus 1 hour and 256 seconds ie 1 hour 4 minutes and 16 seconds. (to save data storage space or something like that).

    10. If the last transmission was at 1707 UTC, the satellite should have started pinging the SATCOM terminal at 1807 UTC.

    11. If the SATCOM terminal had logged off by then, this pinging could have induced the terminal to attempt to log back on, thus the log on request.

    12. However, the log on request came at 1825 UTC, which is 18 minutes later. I do not know the reason for this apparent gap of 18 minutes.

    13. However, Inmarsat has not fully disclosed all the data. There is a gap in the 47 page data log for the period between 1707 UTC and 1803 UTC and for the period between 1803/5 UTC and 1825 UTC.

    14. Could there have been a transmission from the SATCOM system at or just before 1721 UTC the time of the catastrophic event/electrical failure, a fault transmission for example?

    15. Moments before the ADS-B signal ceased, there were a couple of transmissions showing abnormal data.

    16. Could the SATCOM terminal just like the ADS-B transponder transmitted some abnormal/fault data just prior to cessation?

    17. As there is a gap in the Inmarsat data log, we do not know.

    18. If there was such a transmission just before the system went down completely, ie at just before 1721 UTC, the timer at the satellite/GES would have then been set to ping 1 hour later plus or minus 256 seconds.

    19. From the Preliminary Report, the SSR signal ceased at 1.21.13 UTC. One hour and 256 seconds after such time works out to 18.25.29 UTC.

    20. The log on request came in at 18.25.27 UTC.

    21. Finally, all indications are that MH370 had 2 SDUs (see a previous comment) and that it was the back up SDU that transmitted the pings.

    22. Both SDUs had an internal battery. So we do not know if the back up SDU ever ‘powered off’. All we know is that something prompted this SDU to request to log back on at 1825 UTC and in my humble view, it was the satellite pinging which so prompted the SDU.

  17. Gysbregth,

    About the BFO value for the attempted satellite phone call at 18:39 UTC and the inference by some that this shows the plane had turned south by such time.

    1. As everyone would know by now, my own view is that the plane had crashed soon after 1.43am at the South China Sea.

    2. I would like to point out that this call attempt at 18:39 UTC came from another ground station, GES Code 301 ( the one at the Netherlands?) and not the ground station at Perth GES COde 305 from which all other TX transmissions on the Inmarsat data log had originated.

    3. So to compare this BFO value with the other BFO values may be a case of comparing apples with oranges.

    4. The BFO values for this call were 88 to 90. This also happens to be the BFO for MH370 when the plane was stationary at KL.

    5. The Doppler correction mechanism for C Channel may differ from the mechanism for R Channel. Even for a single terminal, there may be more than one way to compute Doppler correction for C Channel, depending on the circumstances prevailing at the time of the call. See for eg this document US 6008758 A ‘Method and apparatus for Doppler compensation in a satellite communications system’.

    6. Even for R channel, the terminal may have more than one method of calculating the Doppler correction. In this regard, I note that the BFO for the R Channel when the plane was at KL was originally at 103/104 but dropped to 85 to 90 after T Channel transmissions came through with BFO values similar to the latter ie 80 plus something.

  18. Question for Richard, or anyone – After the SDU reboots(18.25)the data spears away south. Degraded/altered SDU or a genuine big lefthander? How do we know either way and what is the confidence?

  19. @Matty
    I don’t know, but the Doppler shift due to the velocity of the aircraft is a very large number, many times each of the other contributions. This is compensated by the aircraft satellite terminal using onboard navigation data. If this compensation were to fail the Doppler shift due to the velocity would appear in the BFO and very large numbers would be measured, many hundreds of Hz. That didn’t happen. Subtle problems are not ruled out by that idea, of course.

  20. FYI In the Four Corners MH370 special, they stated that the captain was advised to change the regular flight due to weather, as per the ATC KL…

  21. Alex,

    There are no ‘log-off’ messages in the communication log. The SDU never logged off. You have not explained the log-on requests originating from the SDU at 18:25 and at 00:19.

    You have not provided evidence that the SDU is able to function without external power during more than 7 hours, nor explained that it ceases functioning at the precise time that the available fuel is calculated to run out.

    You have not explained why the SDU, deprived of navigation data, continues to change the radio frequency that it emits on, and the timing delays, in a manner that is only compatible with a path leading to the South Indian Ocean.

    You have not explained, how the SDU with all external wires ‘fried’, is able to transmit data from the IFE (Inflight Entertainment System) at 18:27.

    As I understand it, ACARS is integrated into a larger system and cannot be switched off. If it is unable to send a scheduled message, then it either has no access to VHF or SATCOM communication equipment, or that equipment is inoperative.

    There is no evidence of total electrical failure.

    The GES uplink message at !8:03 was to send ground-to-air Air DATA-2 ACARS data – see Inmarsat release of communication log. Transmission failed because the SDU was unresponsive. You raise an interesting point here – no ‘Log Control – Log-on Interrogation’ message from the GES between 17:07 and 18:25. That deserves an explanation from Inmarsat, but you do not provide it.

    There is no evidence for a ‘gap’ in the communication log data released by Inmarsat.

    That the BFO at 18:40 was similar to that at 16:00 is a coincidence. The value should have been different for a stationary airplane at a different time and place.

    It should not be difficult for Inmarsat to establish and calibrate the Doppler correction mechanism for the C-Channel. The fact that the BFO values on the C-channel at 18:40 and at 23:14 align well with the R-Channel messages indicates that any difference of calibration cannot be large.

  22. Gysbregth,

    I will answer your questions/remarks one by one.

    1. “There is no evidence for a ‘gap’ in the communication log data released by Inmarsat”.

    U obviously have not read the data log closely enough. Just go to the first page showing the various entries (page 3) and tell me where are the entries relating to the first log on request by MH370 when the plane was at KL at 1600 UTC. We have the Log on/Log off Acknowledge, the very first entry but where is the Log On Request that should have preceded that entry? Why did Inmarsat take out the entry/entries relating to the Log On Request?

    Perhaps because Inmarsat did not want people to see that this Log On request did not have a purported ‘fixed offset’ of 4600us?

    If they can take out the first few entries, what makes u think they have not taken out other entries? Have Inmarsat said anything to the effect that the entries in the data log are all the entries recorded? No.

    And we know they excluded almost 20 fields of data from the data log including “SU Contents”, “Rx Power (dBm)”, “C/No”, “Estimated BER” and so on.

  23. Gysbregth,

    “You have not provided evidence that the SDU is able to function without external power during more than 7 hours…..”.

    The back up SDU was functioning until 8.19am. The question is on what power? The regular AC or DC power generated from the plane’s engines or from battery power?

    The SDU had an internal battery. U can verify that by looking up the manual for the MCS series of SDUs which can be found online.

    In addition, neither Boeing nor Honeywell or Malaysia Airlines has come forward to say the SDUs were not hooked up to a secondary power source and/or to a separate dedicated battery.

    It is the authorities who are making the assumption that by virtue of the pings, the plane must still have been flying. They bear the burden of proving that that assumption is valid.

  24. Gysbregth

    “There is no evidence of total electrical failure”.

    The ATSB Report expressly refers to 2 “power interruptions”. Chris Mclaughlin of Inmarsat used a slightly different expression, he said to the effect the plane appeared to have suffered 2 “power failures”. There was a power failure no doubt, but it was just one power failure and it happened at IGARI at 1.21am.

    All communication systems requiring electrical power ceased at 1.21am. Either someone on board had somehow managed to get access to all the circuit breakers and pull them out, all at the same time or there was a total electrical failure at such time. It is now more than 6 months since the plane disappeared and there is not a single shred of evidence that there was anyone on board MH370 who was not a bona fide passenger or crew member.

    The plane took 9 minutes to travel the 37 NM between IGARI and BITOD which works out to a speed of around 240 knots. That is the speed a B777 would glide at, if it had lost all power.

    The plane was at 35000 ft at IGARI but disappeared from ATC primary radar at BITOD showing that it had dropped below the horizon of the radar which was estimated by Professor Stupples at 6000 meters or 20,000 ft ie a drop of around 1500 to 1600 ft per minute. That is the drop rate of a B777 if it had lost power and was merely gliding unpowered.

  25. Gysbregth,

    Yes, there are no log messages disclosed in the Inmarsat data log. There could have been but not disclosed or it could be that there was really no log off messages.

    But once again, surely it is the authorities who bear the burden of explaining why the SDU made a log on request at 1825 UTC? According to the ATSB Report, a log on request in the middle of a flight is “not common”.

    It is the authorities who are claiming the plane was flying all those hours. So if the plane was doing so and everything was fine with the SDU, as u seem to be assuming, then why did it make a log on request at 1825 UTC? It must have already logged on at KL otherwise we would not have all those transmissions up to 1707 UTC , so why did it request to log on at 1825 UTC especially as u said there was no log off?

    I have given an explanation consistent with the evidence that the plane had already crashed by then, that the log on request was prompted by the satellite pinging the terminal after not hearing from the terminal for an hour or so.

    Why don’t u provide an explanation as to why there was such a log on request if the plane was still flying and the SDU was operating as normal, as u seem to be assuming.

  26. Gysbregth,

    I will answer the rest of your questions/remarks as soon as i can find time to do so, u can be assured of that.

  27. Alex,

    Continued operation of the SDU on internal power is the cornerstone of your theory. You have to come up with more convincing references than “The SDU had an internal battery”. My PC too has an internal battery. Its function is to keep track of date and time while the PC is switched off, but the PC cannot operate without external power.

    This is what the ATSB report says about it:

    “There are several reasons why the aircraft satellite data unit (SDU) might generate a SATCOM log on request but an interruption to the aircraft electrical power supply was considered to be the most likely reason.”
    and –
    “… the SDU was designed to ‘hold-up’ during such power interruptions. To experience a power interruption sufficiently long to generate a log on request, it was considered that a loss of both AC buses or, a disabling of the automatic switching, would be required.”

  28. Alex,

    just an additional thought:

    During the design of an airplane and all of its equipment, every gramme of unnecessary weight is trimmed off because it is detrimental to the airplane’s money earning capacity. So why would anyone even consider equipping the SDU with an internal battery of sufficient capacity to allow it to operate without external power during seven hours?

  29. As it’s turned into a bit of a tag team on Alex atm, I’m pretty sure the weight of a battery isn’t a big deal. A plane load of Japanese weighs a lot less than a load of Samoans! About an extra 30 kg per person, do the sums. The margin is quite large and a battery is not a killer. An extra squirt of fuel weighs as much as a battery. Lightning or no lightning, did something happen the South China Sea is the issue. Noone has the right to be talking with any great certitude here. It’s all up in the air.

  30. Alex, I admire your sincerity and your tenacity, but your scenario simply doesn’t work for many technical reasons. Battery power of the back up unit being only one of the issues. I won’t go into detail here myself because others like Gysbrecht have done that comprehensively more than once.
    That said, you make some interesting points concerning the question if the plane ever turned back in the first place. Maybe you should concentrate on those points, and we might try to check pro and contra. The radar evidence is indeed a concern, since nobody knows, who exactly contributed what and who might hold back. Can anybody here dissect Alex’s argument, that the plane was traveling too slow towards BITOD and was sinking below radar horizon? What about Thailand’s radar evidence? That they came out late, doesn’t necessarily mean, it’not true or inaccurate. Is there really a chance that KL 836 could’ve been mixed up with mh 370? We would need to see the exact flight route and the timing of KL 836 on that day. That not a scrap of debris has turned up so far in the South China Sea is of graver concern for a South China Sea crash theory than for a SIO crash scenario, since it’s not nearly as remote and has been searched for two days immediately after the plane went officially missing. No doubt, it should’ve been more thoroughly, but at least it has been done.
    I read Chris McKay’s (the oil rigg worker) eye witness report again yesterday, and it is clear and precise. And he saw the apparently burning object at about the right time. If the SDU hadn’t pinged on for 7 hours, the search area would’ve remained in the South China Sea.
    But if we are really following this trail of thoughts,IMO we have to take the additional step and have to consider the scenario of a cover up of a plane crash. We have to look at possible motives and culprits and how it could’ve been done. We have to enter Brock McEwen’s territory. But first we have to discuss if there is really a chance that the plane crashed into the South China Sea. Anecdotes like the alledged SOS call don’t count for me, btw, since this has never been verified.The same is true for the alledged connection request to Penang tower by the co-pilot’s cell phone. If that had ever been officially endorsed with records to prove it, I’d say case closed – the plane must’ve turned around. But that didn’t happen and I don’t think we can use it as an argument.
    What we can’t do is cherry picking.

  31. Matty,

    I think you miss the point. I can assure you that weight and cost are important considerations for any item of equipment on the airplane, and nothing is installed without a positive cost-benefit analysis.

  32. Gysbrecht – You’re right, and Boeing is one very good company, but an extra case of Beer?

    They might turn up a plane down there I guess but at the moment there is something very wrong with the picture – to me. Some are keen to exonerate all the passengers but the only people who can really do that are the intel services and they are not really obliged to say much. Actually they aren’t saying anything.

    The Iranians in the clear?? A worrying percentage of the Iranian illegals showing up in Australia on irregular boat entries are males under 40 with military experience or background with a defence agency. And they have no documents or shonky ones. I haven’t put that bit to bed yet, along with a heap of stuff. It’s all up in the air – to me.

  33. Littlefoot – On radar I reckon it’s possible they could have been looking at anything. Below is a video of two RAAF F1-11’s going low and hard where they were not meant to be. The observation buildings on the Evans Head range were almost destroyed by the pressure wave. The ceilings came down, eves dislodged, windows gone, furniture spread everywhere. The Australian pilot got demoted, the Canadian on exchange was sent home. Moral of the story – pilots get up to everything. Then there is incompetence.

  34. Mathy

    “… an extra case of Beer?”

    Whether the airplane can carry an extra battery is not the point. From the point of view of cost, weight and maintainability it is not installed unless there is a need for it. Why do you think the batteries of the ULB’s (the underwater locator beacons installed on the CVR and FDR) had a design life of only 30 days?

  35. @Matty, what are you getting at with that video? When I was a small kid btw, fighter jets of the German Luftwaffe behaved like that back in the 1970s. I was frightened to death, when it happened first. Everything was shaking.
    But I don’t think, they mixed up fighter jets with a 777. They are a big blip on the screen. They could’ve mixed up mh 370 with another 777, but then we have to look at their exact flight paths and timing at that very day. A general schedule isn’t good enough.
    This scenario isn’t my favorite one, but I’m willing to discuss an early crash caused by a disaster or by perps, followed by a cover up, since all the tell tale signs that SOMETHING was covered up by some faction were there right from the beginning, unfortunately. Brock listed many of them and named some motive. At least for me it’s more likely than a hypothetically battery powered SDU, springing to life almost 60 minutes after a purported crash, and then pinging away for 7 hours on a floating tail, mimicking by pure chance a flying plane. And then stopping again by pure chance exactly around the time the plane should run out of fuel.

  36. Was Mh 370 disappearance a Cobra training exercise gone wrong and this incident is simply being covered up by the NATO alliance …that’s my ” conspiracy theory”.
    the data I have posted up on Jeff’s blog shows that 777-200 er has a whole lot of potential vulnerabilities
    From the engine fans to the wide open computer system ….

  37. Alex,

    RE YR post at 5:39 AM today:

    I was well aware that the first two messages are missing from the initial Log-on Request sequence. That is not evidence that are gaps in the remainder of the release.

    RE YR post at 5:52 AM today:

    At 8:19 AM (00:19 UTC) a Log-on Request was received from the airborne terminal, most probably because power to the terminal was interrupted “sufficiently long to force a shutdown” of the terminal. The ATSB states that the SDU is powered by the left AC bus and describes the automatic power supply switching. There is no mention of battery power and I think that would be unlikely anyway because SATCOM is not essential for continuation of flight in the event of loss of generated power (incidentally, another reason that 7 hrs of internal battery power supply is unlikely).

    The ATSB has described their reasoning in much detail supported with reasonable arguments. If you have a different theory the burden of providing proof in support of that theory is entirely yours.

    RE YR post at 6:06 AM today:

    The ATSB report refers to power interruptions apparent in the functioning of the SDU. Whatever caused those interruptions, it is not evidence of total electrical failure. The ATC transponder can be silenced by selecting the STDBY position of the rotary selector switch. ATS-B may well be routed through that same transponder. The absence of communication via VHF is not evidence that VHF was inoperative.

    I have no data for the flight between IGARI and BITOD, but as a former glider pilot you should know that loss of power does not dictate a particular speed. A 777 can glide at any speed between approximately 180 and 550 knots.

    Since it is unclear which radar saw MH370 at that time, I have no comment on your last paragraph.

    RE YR post at 6:21 AM today:

    The ATSB gives several possible causes for an in-flight log-on request, the most likely being an interruption of the power supply to the SDU.

    As to satellite pinging being the cause, you have noted earlier that the logs contain no pinging messages between 1707 and 1825.

    Since the SDU is powered by the left AC bus, someone must have restored power to that bus at about 18:25. It is unlikely that this was done to restore power to the SDU, so doubtless the investigators will be interested in the reason for that change, i.e. what other services are powered by the left AC bus. There is no indication that the SDU was not operating normally, except that it was apparently not powered during certain periods.

    RE YR post at 6:30 AM today:

    I’m looking forward to the rest of your answers.

  38. @Richard – you wrote:

    “If this compensation were to fail the Doppler shift due to the velocity would appear in the BFO and very large numbers would be measured, many hundreds of Hz.”

    Is this ALWAYS true? I honestly don’t know what the BFO would look like if the plane is directly away at 500kts. But if it’s flying a path tangent to the satellite, or towards it, then it could be much lower.

    It seems like there’s some circular logic here: “We know the plane turned south because the BFO said so, and we know the BFO is properly compensated because the plane turned south.”

    I’m not suggesting that this is wrong, nor do I believe this is settled fact either, and with no other corroborating data putting the plane south of the equator, we can’t rule out a ground-based, spoofed signal steering us to a place in the SIO where we might never find the plane, even if it’s there. It brings to mind a recently convicted killer stating that she disposed of the murder weapon in the desert. True or false, it’s a wild goose chase – a very clever but simple way to hide the truth.

    @Alex – I think for the crashed-SDU theory to work, you need the following:

    1. A business case for ANY battery on an SDU
    2. A showing that the battery can power the SDU for 7 hours.
    3. An explanation for the SDU’s reboot.

    Item 1 can be made easily – to prevent minor hiccups from jamming up satellite bandwidth.

    Item 2? By design, this is highly unlikely. However, we are only talking about a handful of transmissions. The 7 hours is misleading – it’s not a flashlight, nor is it pinging every minute or every second. It is basically on standby. The battery could conceivably be a cell phone battery and do its job. Or, maybe not, depending on the SDU’s power draw while 1) receiving, and 2) transmitting.

    Regardless, some numbers would help here.

  39. Gysbreght – If there was a safety angle to having a battery in the SDU then they could/would do it.

    Littlefoot – what I’m getting at with the video is pilot behaviour. Not suggesting they saw a rogue Mig.

  40. Littlefoot – “and then pinging away for 7 hours on a floating tail, mimicking by pure chance a flying plane.”

    For ages I jumped up and down in ignorance because there was no test flight. Now I learn it was always pointless for a number of reasons including the weather! That’s how volatile these numbers are and modeling is still dependant on some limited data splices from flights that crossed parts of the alleged route that night. Remember for a moment that these numbers are not replicable in any way and can be swayed by anything including the weather. It started out a tenuous heads/tails delineation, now it’s a crime scene reconstruction. That’s before we go into the state of the SDU???

    The numbers have frown in stature not because they good numbers, because more and more energy has gone into them. Could end badly.

  41. I have to admit – since Alex introduced the “Floating SDU” theory, I envisioned a 100-lb lead-acid battery required to keep power to the unit.

    I am moving away from that position. That doesn’t mean the theory explains the numbers, but I no longer see it as unrealistic to maintain power for 7 hours.

    I looked up the battery specs on some satellite phones. I found a 2006 model called the GSP-1700. It contains a 2500mah lithium ion battery.

    That is approximately double the capacity in an iPhone. Battery technology over the years changes dramatically, but let’s say that if built today, the battery would be a little smaller than an iPhone. Built in 1980, it might be as big as a beer can.

    With that battery capacity, the satellite phone has a talk time of 4 hours, and a standby of 36 hours. Presumably, the technology uses the same Inmarsat satellite, or one of comparable design by a competitor.

    For practical purposes, therefore, a battery weighing a few ounces is clearly sufficient to send a few milliseconds of digital signal over a period of 7 hours.

    So the question isn’t whether there is a business case. The question is whether the battery on the SDU, put there merely to prevent power hiccups, is also large enough to receive for 7 hours.

    While weight may be an overwhelming factor in airplane design, for a battery this size, we are at the point of diminishing returns, especially considering the standardization of batteries around the 1200mah size and the very minimal uses for batteries much smaller than that until you get into watch and clock batteries.

    So I have to say, it no longer sounds impossible for an intact SDU to be transmitting a mere handful of pings for 7 hours without bus power. I’d welcome opposing calculations.

  42. Littlefoot – and it’s also an opportunity to get my favourite plane in there. F111 !!!

  43. Gysbregth,

    “You have not explained why the SDU, deprived of navigation data, continues to change the radio frequency that it emits on, and the timing delays, in a manner that is only compatible with a path leading to the South Indian Ocean”.

    1. The simple answer to this question is that something was moving in the direction of the South Indian Ocean during the pings, but it was not the plane. It was the satellite.

    2. The movement of the satellite would result in changing BTO and BFO values even if the plane had crashed. It is expressly stated in the Inmarsat 47 page data log the terminal on MH370 ‘assumes a stationary satellite at a fixed orbital position’ for Doppler correction. Likewise, for the calculation of the BTOs, we have it from high authority in the form of the Independent Group that Inmarsat’s algorithm also assumes a stationary satellite for such calculations. (see the comments of Bill, a member of the group, on Duncan’s blog).

    3. The primary system for Doppler correction for MH370 is the closed loop system (see the manual found online for the MCS series 4200/7200). The closed loop system requires navigational input (heading, altitude velocity etc of the plane) for proper Doppler correction calculations.

    4. Without such input (from the IRS via AIMS) the calculations for both the BTOs and BFOs will end up a function of the satellite movement and velocity. Which is exactly what we see in the data. Incorrect BTOs and BFOs that are a function of the movement and velocity of the satellite and thus pointing to a path to the north initially when the satellite was moving north and then southwards on a 180 degree heading ie to the South Indian Ocean, not later than the second ping at 1941 UTC after the satellite turned at 1936 UTC and from such time traveled southwards.

  44. Gysbregth

    “You have not explained, how the SDU with all the external wires fried, is able to transmit data from the IFE (Inflight Entertainment System) at 18:27”.

    It is stated at page 22 of the ATSB Report: “Approximately 90 seconds after the 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 log on request, however none were received. This could indicate a complete loss of generated electrical power shortly after the 7th handshake”.

    1. U will note from my previous comments, MH370 by all indications, had 2 SDUs, a primary SDU and a back up SDU operating on a master/slave basis ( see the MCS series manual).

    2. The back up SDU linked directly to the back up Low Gain Antenna is designed to come on only after the primary system has failed. See ARINC 741, the industry standard for the design of SATCOM systems, the comprehensive post on March 15th on the flyertalk forum and the MCS series manual.

    3. In other words, there was redundancy in the MH370 SATCOM system; there was a back up system.

    4. I am no expert but my guess is the back up SDU escaped harm’s way when the current from the lightning strike surged through the plane, because it was designed to be out of harm’s way, coming on only as a back up when the primary system is no longer functioning. Whether it was on a cold, warm or hot standby mode, I do not know.

    5. As the main system was knocked out, ACARS would have ceased and that is what we see, ACARS ceased some time between 1707 UTC and 1737 UTC, in all likelihood at 1721 UTC when the catastrophic event occurred.

    6. According to the manual, the back up SDU through the LGA, can only transmit ‘low rate packet data’. Thus when it logged on at 1825 UTC, it would have been a Class 1 log on (limited to such data) as compared to the original log on at 1600 UTC which would be for all data and voice ie a Class 3 log on.

    7. The communications from the IFE must have been in process when the catastrophic event struck breaking the link between the primary SATCOM system and the satellite.

    8. When the back up SDU logged back on at 1825 UTC, these IFE data (or the part of such data which can be transmitted on a Class 1 log on) which were already in the system ready for transmission, were transmitted by the back up SDU.

    9. People have speculated these IFE data related to credit card data in respect of payments made by passengers for the IFE on offer on a pay on demand basis.

    10. As stated in the ATSB Report, no such IFE data were transmitted during the log on at 8.19am. That is because the plane had crashed many hours ago, soon after 1.43am, so the question of any passenger having used the IFE after 1743 UTC or 1.43am, would not arise.

  45. Gysbregth,

    “As i understand it, ACARS is integrated into a larger system and cannot be switched off. If it is unable to send a scheduled message, then it either has no access to VHF or SATCOM communication equipment, or that equipment is inoperative”.

    1. VictorI and Don, in their exchange of comments on Duncan’s blog which have been quoted in a previous comment, had shown how the SDU would still have been able to respond to the satellite interrogation despite ACARS being down.

    2. Basically ACARS is in the nature of an App, just because this App was down does not mean the terminal could not function on some other more basic level.

    3. After the log on, the SDU did not do anything other than (a) responding to the satellite’s hourly interrogation by emitting these most basic of level “I am here” signals or pings and (b) “acknowledging” the 2 attempted satellite phone calls from the ground. It did not initiate anything.

    4. Pretty much like a handphone with no Apps, but with a battery and thus still able to emit the same ‘I am here’ signal in response to the pinging from a cell tower.

  46. Gysbregth,

    “That the BFO at 18.40 was similar to that at 16:00 is a coincidence. The value should have been different for a stationary airplane at a different time and place”.

    1. U may well be right that it is a coincidence. I just pointed it out in case some people may be able to discern something from this apparent coincidence.

    2. I have a gut feeling the data for this call which was routed from GES 301 (Burum, Netherlands), may ultimately yield some vital clues as to the whereabouts of the plane. For one thing, it means there is data for comparison and also some sort of “triangulation”, maybe.

    3. While we are on the topic of ‘triangulation’, is there the possibility that the pings were also picked up by another satellite, whether belonging to Inmarsat or otherwise? Just a thought.

  47. Alex – there was a presumption in many quarters that the pings would have registered elsewhere. Plenty of satellites out there, but nothing ever popped out?

  48. @JS
    >Is this ALWAYS true? I honestly don’t know what the BFO would look like
    >if the plane is directly away at 500kts. But if it’s flying a path tangent to the
    >satellite, or towards it, then it could be much lower.

    The BTO was changing so range to the satellite was also changing, ruling out tangential paths.

    >It seems like there’s some circular logic here: “We know the plane turned south
    >because the BFO said so, and we know the BFO is properly compensated because the plane turned south.”

    The analysis of the BTO/BFO data requires that the equipment was working correctly. If it wasn’t there is no way to analyse it or find the aircraft.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.