Malaysian Airlines MH370 contact lost
the unresponsive crew/ hypoxia event type appeared to best fit the available evidence
Yes. But likely quite different profiles after fuel exhaustion. Is 90 odd km sufficient to encompass a glide for max range? I don't think so.
There will have been careful consideration of diplomacy in this document. Also carefully worded disclaimers to minimise any criticism in case of an alternative ultimate explanation. "Hey that was not our responsibility and was not relevant to our role."
It is certain there was very careful consideration given to every comment that even hints at cause in a document of this nature.
There will have been careful consideration of diplomacy in this document. Also carefully worded disclaimers to minimise any criticism in case of an alternative ultimate explanation. "Hey that was not our responsibility and was not relevant to our role."
It is certain there was very careful consideration given to every comment that even hints at cause in a document of this nature.
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I am wondering about one thing in the definion of the search area report:
If the AP had been off for that long, how could the satellite system log on? Doesn't it require a directional antenna? Wouldn't a spiral dive already have developed after 3 minutes, making any directional antenna use impossible? Or is the tracking that quick?
Balancing this was the consideration that, by the time of the final SATCOM log on message, the autopilot could have been disengaged for approximately 3 minutes and 40 seconds and the aircraft would have been descending during that period
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ATSB - Update 18 August 2014
Since the public release of the report 'MH370 – Definition of Underwater Search Areas' on 26 June 2014, the ATSB has received a number of queries about some of the technical details contained in the report. The queries have been made directly to the ATSB or through the Chief Commissioner’s blog, InFocus, on the ATSB website.
As a result of the queries, the ATSB is today releasing an updated version of the report to clarify a number of technical aspects. The changes to the report are detailed in the Addendum on the inside cover.
MH370 - Definition of Underwater Search Areas -PDF: 7.33MB- (updated 18 August 2014)
Since the public release of the report 'MH370 – Definition of Underwater Search Areas' on 26 June 2014, the ATSB has received a number of queries about some of the technical details contained in the report. The queries have been made directly to the ATSB or through the Chief Commissioner’s blog, InFocus, on the ATSB website.
As a result of the queries, the ATSB is today releasing an updated version of the report to clarify a number of technical aspects. The changes to the report are detailed in the Addendum on the inside cover.
MH370 - Definition of Underwater Search Areas -PDF: 7.33MB- (updated 18 August 2014)
Civilian shipping
Something that does not seem to be in the ATSB report us an analysis of civilian shipping location and course at the time of the 7th partial handshake. The information we do have is the exact time of this transmission, and the location of this arc. The location of ships in the vicinity of this arc at that time is surely available.
The ocean is huge and shipping is fairly low in density relative to other waters. However there is a reasonable amount of shipping between Australia and South Africa - the sea lane of most relevance to MH370. Many of the tracking services are only accessible via paid subscription. However one historical graphic I was able to find shows 1920 vessels in the Indian ocean for 6th April 2012, with a small minority of these in the general area of interest.
Given we have an absence of positive information (i.e. something seen), have we made all possible use of negative information. Might it help define the most likely areas to search if we use reports of what was NOT seen.
Sure any ships in the area could easily have missed something. There are countless stories from shipwrecked people ultimately rescued of not being seen by a passing ship.
However everything about the proposed new search area is based on analysis of various probabilities and compromises - which is logical given we can't search everywhere.
So could we assign (admittedly somewhat arbitrary) values for the probability of a ship seeing something had it been in the right area e.g. 777 spiralling into ocean, or a fresh debris field. Looking at the solar terminator at the time of the final handshake, it was daylight in the proposed search area. That increases the probability something would have been seen by a ship in the right place.
Can we use this information to calculate adjusted probabilities (i.e. MH370 less likely in this area as a ship in that area didn't see anything, and correspondingly other areas become more likely).
The ocean is huge and shipping is fairly low in density relative to other waters. However there is a reasonable amount of shipping between Australia and South Africa - the sea lane of most relevance to MH370. Many of the tracking services are only accessible via paid subscription. However one historical graphic I was able to find shows 1920 vessels in the Indian ocean for 6th April 2012, with a small minority of these in the general area of interest.
Given we have an absence of positive information (i.e. something seen), have we made all possible use of negative information. Might it help define the most likely areas to search if we use reports of what was NOT seen.
Sure any ships in the area could easily have missed something. There are countless stories from shipwrecked people ultimately rescued of not being seen by a passing ship.
However everything about the proposed new search area is based on analysis of various probabilities and compromises - which is logical given we can't search everywhere.
So could we assign (admittedly somewhat arbitrary) values for the probability of a ship seeing something had it been in the right area e.g. 777 spiralling into ocean, or a fresh debris field. Looking at the solar terminator at the time of the final handshake, it was daylight in the proposed search area. That increases the probability something would have been seen by a ship in the right place.
Can we use this information to calculate adjusted probabilities (i.e. MH370 less likely in this area as a ship in that area didn't see anything, and correspondingly other areas become more likely).
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"Hmmm... I would have assumed it was a phased array conformal antenna" - Astramike
You are correct Sir, and I am wrong. There is a non steerable low gain antenna on the roof of the T7 but there is also a phased array high gain antenna.
The phased array antenna is an Esterline CMC Electronics Inc (Canada) model CMA-2102SB (source airframer.com)
It is 60" long, 18" wide and 4.5" high, takes 69 watts, can switch the beam in 50 microseconds and offers a minimum of 9dBiC gain over 100% of the hemisphere above the horizon. Looking straight up it gives 17dBiC gain.
dBiC is decibels of gain of the antenna relative to an isotropic antenna (no gain) dealing with a circularly polarized EM field.
The gains offered by this antenna range from 2 to 7 relative to an omnidirectional antenna.
You are correct Sir, and I am wrong. There is a non steerable low gain antenna on the roof of the T7 but there is also a phased array high gain antenna.
The phased array antenna is an Esterline CMC Electronics Inc (Canada) model CMA-2102SB (source airframer.com)
It is 60" long, 18" wide and 4.5" high, takes 69 watts, can switch the beam in 50 microseconds and offers a minimum of 9dBiC gain over 100% of the hemisphere above the horizon. Looking straight up it gives 17dBiC gain.
dBiC is decibels of gain of the antenna relative to an isotropic antenna (no gain) dealing with a circularly polarized EM field.
The gains offered by this antenna range from 2 to 7 relative to an omnidirectional antenna.
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MH370: Malaysian Firm Says Chinese Hackers Took Classified Data From Investigators’ C
MH370: Malaysian Firm Says Chinese Hackers Took Classified Data From Investigators? Computers
Chinese hackers targeted the computers of high-ranking officials at agencies involved in the investigation of Malaysia Airlines Flight MH370, just a day after it went missing, and stole classified information, a Malaysian newspaper said Wednesday.
Chinese hackers targeted the computers of high-ranking officials at agencies involved in the investigation of Malaysia Airlines Flight MH370, just a day after it went missing, and stole classified information, a Malaysian newspaper said Wednesday.
MH370: Revised search focus
The West Australian newspaper is reporting today :
Fresh information suggested the jet "may have turned south" earlier than thought, Deputy Prime Minister Warren Truss said.
The detail came to light following "further refinement" of satellite data and as investigators attempted to map the plane's position during a failed attempt to contact it earlier in its flight path.
"After MH370 disappeared from the radar, Malaysia Airlines ground staff sought to make contact using a satellite phone. That was unsuccessful," he said.
"But the detailed research that's being done now has been able to... trace that phone call and help position the aircraft and the direction it was travelling."
The minister said investigators still believed MH370 was somewhere on the search zone's seventh arc, where it emitted a final satellite "handshake".
"It remains on the seventh arc - that is, there is a very, very strong view that this aircraft will be resting on the seventh arc," he said.
Fresh information suggested the jet "may have turned south" earlier than thought, Deputy Prime Minister Warren Truss said.
The detail came to light following "further refinement" of satellite data and as investigators attempted to map the plane's position during a failed attempt to contact it earlier in its flight path.
"After MH370 disappeared from the radar, Malaysia Airlines ground staff sought to make contact using a satellite phone. That was unsuccessful," he said.
"But the detailed research that's being done now has been able to... trace that phone call and help position the aircraft and the direction it was travelling."
The minister said investigators still believed MH370 was somewhere on the search zone's seventh arc, where it emitted a final satellite "handshake".
"It remains on the seventh arc - that is, there is a very, very strong view that this aircraft will be resting on the seventh arc," he said.
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A further report in the Guardian today
MH370: satellite phone call revealed as Australia gives update on search | World news | theguardian.com
I am still surprised that there has been no comment in the ATSB report on any attempt to establish whether any passenger or crew mobile phones were left on by mistake.
MH370: satellite phone call revealed as Australia gives update on search | World news | theguardian.com
I am still surprised that there has been no comment in the ATSB report on any attempt to establish whether any passenger or crew mobile phones were left on by mistake.
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"A further report in the Guardian today
MH370: satellite phone call revealed as Australia gives update on search..."
The article probably comes from this Communiqué:
MH370 Tripartite Meeting
Hope we have a full transcript, because the fact about "the revelation of a phone call" is not written in the Communiqué.
MH370: satellite phone call revealed as Australia gives update on search..."
The article probably comes from this Communiqué:
MH370 Tripartite Meeting
Hope we have a full transcript, because the fact about "the revelation of a phone call" is not written in the Communiqué.
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Whilst public attention is focused on the search effort, no reports are released on the criminal investigation which continues under wraps. Is it not high time the authorities release some information as to progress on this aspect of the search for answers.
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The Inmarsat Communication Log provides the following details:-
Remarks in [brackets] added by me, and a duplication of the BURUM data in the log is not reproduced here.
The unanswered call was routed via BURUM in the Netherlands. While the most relevant thing is that PERTH checked the call progress and subsequent release, which resulted in two BFO's.
18:39 - Ground Initiated to Air Telephony Call - Zero Duration (Not Answered)
18:39:52.907 | IOR-P10500-0-386B | IOR | 301 [BURUM NL] | 10 | P-Channel TX | 0x20 - Access Request/ Call Announcement Telephone/ Circuit-Mode Data
18:39:52.907 | IOR-P10500-0-386B | IOR | 301 [BURUM NL] | 10 | P-Channel TX | 0x33 - C-Channel Assignment (Regularity)
18:39:55.354 | IOR-3730-21000 .... | IOR | 305 [PERTH AU] | 06 | C-Channel RX | 0x30 - Call Progress - Test | 88 [BFO]
18:40:56.354 | IOR-3730-21000 .... | IOR | 305 [PERTH AU] | 06 | C-Channel RX | 0x30 - Call Progress - Channel Release | 90 [BFO]
18:39:52.907 | IOR-P10500-0-386B | IOR | 301 [BURUM NL] | 10 | P-Channel TX | 0x20 - Access Request/ Call Announcement Telephone/ Circuit-Mode Data
18:39:52.907 | IOR-P10500-0-386B | IOR | 301 [BURUM NL] | 10 | P-Channel TX | 0x33 - C-Channel Assignment (Regularity)
18:39:55.354 | IOR-3730-21000 .... | IOR | 305 [PERTH AU] | 06 | C-Channel RX | 0x30 - Call Progress - Test | 88 [BFO]
18:40:56.354 | IOR-3730-21000 .... | IOR | 305 [PERTH AU] | 06 | C-Channel RX | 0x30 - Call Progress - Channel Release | 90 [BFO]
The unanswered call was routed via BURUM in the Netherlands. While the most relevant thing is that PERTH checked the call progress and subsequent release, which resulted in two BFO's.
The Inmarsat Communication Log provides the following details:-
Remarks in [brackets] added by me, and a duplication of the BURUM data in the log is not reproduced here.
The unanswered call was routed via BURUM in the Netherlands. While the most relevant thing is that PERTH checked the call progress and subsequent release, which resulted in two BFO's.
Remarks in [brackets] added by me, and a duplication of the BURUM data in the log is not reproduced here.
The unanswered call was routed via BURUM in the Netherlands. While the most relevant thing is that PERTH checked the call progress and subsequent release, which resulted in two BFO's.
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I'm not sure how you get 441 kt (I get ~360), but yes, that's more or less what it means. BFO 88 Hz is in line with later BFO points and it's a good indication that the turn south was completed by 18:40. I don't know if that's the point they are trying to make. This data was available from the beginning and I would've assumed that it was included in original estimates.
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Back to the satcom system.There is no single high gain antenna on top center.
http://www.upload-pictures.de/bild.p...hgainJ9U9R.jpg
Photos: Boeing 777-2H6/ER Aircraft Pictures | Airliners.net
http://www.upload-pictures.de/bild.p...hgainJ9U9R.jpg
Photos: Boeing 777-2H6/ER Aircraft Pictures | Airliners.net
Its a bit hard to follow why the BFO analysis from the 1839 satellite call changes things now. They presumably had this information before. But the media release certainly suggests this data is being used to refine the most likely search area.
Anyway if we accept the location of the last primary contact at 1822, this fits pretty well with the first "ring" at 1825. Unlikely the plane turned south between 1822 and 1825 as this would have taken it over land.
Then a turn to the south by 1840 - not long after passing the "tip" of Sumatra.
Its hard to identify a constant course that would hit all the rings at the right time. Best fit appears to be close to due south - although the distance covered between the 2141 and 2241 rings seems a bit large.
Assuming the last ring = fuel exhaustion and crash, we know the plane flew for a defined time from last known point. We can estimate an interval of most likely speeds from the fuel load and fuel consumption. So we can estimate an interval of most likely distance covered from last known point. An earlier turn south doesn't change the known duration, nor the estimated velocity or distance covered. These stay constant.
So an earlier turn south presumably puts the crash a bit further south west along the 7th arc.
Anyway if we accept the location of the last primary contact at 1822, this fits pretty well with the first "ring" at 1825. Unlikely the plane turned south between 1822 and 1825 as this would have taken it over land.
Then a turn to the south by 1840 - not long after passing the "tip" of Sumatra.
Its hard to identify a constant course that would hit all the rings at the right time. Best fit appears to be close to due south - although the distance covered between the 2141 and 2241 rings seems a bit large.
Assuming the last ring = fuel exhaustion and crash, we know the plane flew for a defined time from last known point. We can estimate an interval of most likely speeds from the fuel load and fuel consumption. So we can estimate an interval of most likely distance covered from last known point. An earlier turn south doesn't change the known duration, nor the estimated velocity or distance covered. These stay constant.
So an earlier turn south presumably puts the crash a bit further south west along the 7th arc.
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Something that does not seem to be in the ATSB report us an analysis of civilian shipping location and course at the time of the 7th partial handshake. The information we do have is the exact time of this transmission, and the location of this arc. The location of ships in the vicinity of this arc at that time is surely available.
So unless the aircraft appeared and was recorded on radar as it impacted I doubt anyone saw anything. Might be different if it was on fire though?