[Peetwo]

Latest JACC MH370 SIO search update - Additional Fugro vessel.

Joint Agency Coordination Centre MH370 Operational Search Update

25 November 2015

This operational report has been developed to provide regular updates on the progress of the search effort for MH370. Our work will continue to be thorough and methodical, so sometimes weekly progress may seem slow. Please be assured that work is continuing and is aimed at finding MH370 as quickly as possible.

Key developments this week

• Fugro Discovery is en route to Fremantle, evacuating an unwell crew member. The vessel is expected to arrive in port on Friday 27 November and conduct resupply before returning to the search area.
  
• Fugro Equator continues to conduct bathymetry and underwater search operations in the search area.
  
• A third search vessel, Havila Harmony is currently being mobilised with the Hugin 4500 Autonomous Underwater Vehicle (AUV) search system at the Australian Marine Complex at Henderson, south of Fremantle.  
  
  

Medical evacuation
A crew member on the search vessel Fugro Discovery has fallen ill, suffering from severe pain. The vessel halted search operations on Saturday 21 November, recovering the towfish and commencing transit back to Fremantle. The full-time doctor on Fugro Discovery is attending to the crew member in consultation with onshore medical support.

The remoteness of the search area has been an ongoing challenge in the search for MH370. At the time the crew member became unwell, Fugro Discovery was approximately 2,800 kilometres from Fremantle – well beyond the range of any land-based helicopter.

The only viable option was to return to port.

This incident is a reminder of the difficult conditions in which crew members work. The vessels spend 42 days at sea between port calls in weather conditions which can be physically arduous and fatiguing for the crew. Some of the work performed can be hazardous, particularly handling the heavy deep tow search system on a ships’s wet deck moving in a seaway.

The risk of a serious illness or injury on board a search vessel is a real possibility and for this reason the vessels have a doctor on board with appropriate medical equipment and supplies. The risk of a medical emergency is partly mitigated with regular health checks for the crew and a comprehensive system of safe working procedures, however incidents can and will occur.

Underwater search operations
The search area has been expanded beyond an original 60,000 square kilometre search area to enable up to 120,000 square kilometres to be searched if required.

Weather continues to impact on search operations but conditions are expected to be improved over the coming months. The safety of the search crews, as always, remains a priority, and the vessels and equipment utilised will vary to reflect operational needs.
More than 70,000 square kilometres of the seafloor have been searched so far.

Havila Harmony is a Fugro vessel and will have the Hugin 4500 autonomous underwater vehicle (AUV) on board. After calibration trials off the coast of Fremantle, the vessel is expected to depart for the search area on Saturday for an expected arrival date in the the search area of 3 December.  The AUV will again be used to survey the most difficult portions of the search area that cannot be searched as effectively by the deep tow search systems on the other search vessels.

The Search Strategy Working Group continues to review evidence associated with MH370, which may result in further refinement of, or prioritisation within, the search area.

In the event the aircraft is found and accessible, Australia, Malaysia and the People’s Republic of China have agreed to plans for recovery activities, including securing all the evidence necessary for the accident investigation.

Click map to enlarge

[i]Click map to enlarge[/i]
 
Weather
Weather is forecast to be favourable for the coming week.
 
 
 

---

Previous versions:

• MH370 Operational Search Updates
  

Related: MH370

MTF...P2

[ventus45]

It is "interesting" that the Chinese Government has "apparently" got "interested" in the search again.

Having spent over a year "painfully, obviously, and distainfully disinterested" in the "East of Ninety Farce", I wonder why they seem willing to "re-engage"  "now" ?  

The Chinese Government has always (from the earliest days) favoured an area around, and south of, 85E 40S.

As the ATSB gradually inches towards there, does Simon's position(s) "interest" them ?

Supplying "money" to the Malaysian Seearch ( "effectively" sub-contracted to Australia ) was "never" in their creed.  Will they help fund the existing search, or will they "spend" their money on sending one ( or more ) of their own ship(s) to search their own preferred area, "independently" ?

Then, what if "they" find it ?
Specifically, what if they find the starboard wing, and that "control surface", ( or remnants of it ) are still there ?

In that event, I don't think the existing:
"In the event the aircraft is found and accessible, Australia, Malaysia and the People’s Republic of China have agreed to plans for recovery activities, including securing all the evidence necessary for the accident investigation."
will be worth the paper it is written on.

If that particular control surface ( or remnants of it ) is still there, it will sink Malaysia's credibility, ( and Australia's ), and "all bets" will be off.

Interesting times ahead - perhaps.

[ventus45]

Ok guys, what do you think of this (pages 10 and 11) ?

A paper by Kai Fan and Katherine Heller of Duke University dated 16th November 2015.

Title: - "k-means: Fighting against Degeneracy in Sequential Monte Carlo with an Application to Tracking"

http://arxiv.org/pdf/1511.04157.pdf

Related path graphics videos.

https://youtu.be/bFx2DeengXY

https://youtu.be/pgC3f65y_ZE

[Peetwo]

Ok guys, what do you think of this (pages 10 and 11) ?

A paper by Kai Fan and Katherine Heller of Duke University dated 16th November 2015.

Title: -   "k-means:  Fighting against Degeneracy in Sequential Monte Carlo with an Application to Tracking"

http://arxiv.org/pdf/1511.04157.pdf



Related path graphics videos.

P2

[Peetwo]

This AM courtesy of PlaneTalking.. :

MH370: Live notes from special update

Ben Sandilands | Dec 03, 2015 10:14AM |



Malaysia Airlines 777-200ER 9M-MRO, which flew the ill fated MH370 service

An update on the search for missing Malaysia Airlines flight MH370 is being held at around 1030 eastern Australian daylight time in Canberra. The key points will be logged here, followed as necessary by a considered review of the new information.
The media alert makes no reference to the finding of MH370.

Deputy Prime Minister and Minister for Infrastructure and Regional Development Warren Truss and Assistant Minister for Defence Darren Chester will hold a press conference this morning on updated analysis of the search for missing Malaysian Airlines flight MH 370.
 
Defence Science and Technology Group has provided further analysis to inform the Australian Transport Safety Bureau’s latest report: MH 370 – Definition of Underwater Search Area Update, which reaffirms the highest probability of the resting place of the aircraft in the current 120,000 sq km search zone.
 
The report will be released today.
 
Following the Ministers’ press conference [at 1230] the ATSB will conduct a separate technical briefing on the report for interested media.

MH370 with 239 people on board was en route from Kuala Lumpur to Beijing on 8 March 2014 when it disappeared as a transponder identified flight on air traffic control consoles while at 35,000 feet over the Gulf of Thailand.

Notes: Australia commissioned its own review of previous advice on the likely path taken by MH370 to ‘inform’ the new ATSB report on the definition of the underwater search area, and has released it today.

The deputy PM Warren Truss described the new report as ‘fairly heavy technical reading’.
He said the key points made by the new Defence Science and Technology Group confirmed the broad conclusions made by the strategic search panel that the jet turned south and flew to a point along the so-called seventh arc of possible locations of its point of impact with the water over the southern Indian Ocean.

At this point live television coverage in Australia switched back to the mass shooting tragedy in San Bernardino, and it would be fair to say, any aviation reporters living in SE Australia felt relieved that they hadn’t jumped in their cars in an attempt to reach Canberra in time to receive these new insights.

However, the new report hasn’t yet been studied in detail, and there is an ATSB press conference to come in less than two hours time.

 
MTF?- Definitely..P2

[ventus45]

3rd December 2015

Latest Update on search for MH-370

ATSB - cANBERRA

https://www.atsb.gov.au/publications/inv...4-054.aspx

https://www.atsb.gov.au/media/5733650/AE...ec2015.pdf

https://www.atsb.gov.au/media/5733804/Ba...ec2015.pdf

JACC - cANBERRA

https://www.atsb.gov.au/mh370-pages/upda...pdate.aspx

[Peetwo]

This AM courtesy of PlaneTalking.. :

MH370: Live notes from special update

Ben Sandilands | Dec 03, 2015 10:14AM |



Malaysia Airlines 777-200ER 9M-MRO, which flew the ill fated MH370 service

An update on the search for missing Malaysia Airlines flight MH370 is being held at around 1030 eastern Australian daylight time in Canberra. The key points will be logged here, followed as necessary by a considered review of the new information.
The media alert makes no reference to the finding of MH370.

Deputy Prime Minister and Minister for Infrastructure and Regional Development Warren Truss and Assistant Minister for Defence Darren Chester will hold a press conference this morning on updated analysis of the search for missing Malaysian Airlines flight MH 370.
 
Defence Science and Technology Group has provided further analysis to inform the Australian Transport Safety Bureau’s latest report: MH 370 – Definition of Underwater Search Area Update, which reaffirms the highest probability of the resting place of the aircraft in the current 120,000 sq km search zone.
 
The report will be released today.
 
Following the Ministers’ press conference [at 1230] the ATSB will conduct a separate technical briefing on the report for interested media.

MH370 with 239 people on board was en route from Kuala Lumpur to Beijing on 8 March 2014 when it disappeared as a transponder identified flight on air traffic control consoles while at 35,000 feet over the Gulf of Thailand.

Notes: Australia commissioned its own review of previous advice on the likely path taken by MH370 to ‘inform’ the new ATSB report on the definition of the underwater search area, and has released it today.

The deputy PM Warren Truss described the new report as ‘fairly heavy technical reading’.
He said the key points made by the new Defence Science and Technology Group confirmed the broad conclusions made by the strategic search panel that the jet turned south and flew to a point along the so-called seventh arc of possible locations of its point of impact with the water over the southern Indian Ocean.

At this point live television coverage in Australia switched back to the mass shooting tragedy in San Bernardino, and it would be fair to say, any aviation reporters living in SE Australia felt relieved that they hadn’t jumped in their cars in an attempt to reach Canberra in time to receive these new insights.

However, the new report hasn’t yet been studied in detail, and there is an ATSB press conference to come in less than two hours time.

Oh no BBB is back??

With beard 'a splendid' it would seem you can't keep our MH370 Super Sleuth Muppet out of the limelight indefinitely, here he is mi-mi-mi-ing around with the mi-mi-mi-miniscule...

   
Hmm...notice how the other dude - Assistant Minister for Defence Darren Chester - tries in vane to make himself scarce...   Can't say I blame him, I think I'd rather chew my arm off rather than be handcuffed to either of those two buffoons..


MTF..P2   

[ventus45]

P2,
(1) Was there a part 3 ? The end of pt-2 is abrupt.
(2) Have you any video of the additional ATSB brief that was to have been at 12:30pm ?

[Gobbledock]

Ami mi mi mi mi azing. Not!

What a load of old cobblers. A lisping, bumbling crustacean head Farmer and a furry faced mumbling numpty called Dolan! Incidentally the word 'Dolan' sounds to me like a Scottish turd ( i.e "I gotta go drop a Dolan"). Besides I would rather wear Amanda Vanstone's two day granny panties over my head than listen to that interview.

P.S Does Beaker look more like Father Christmas this year? With a greyer and fuller and more fluffy beard. Does it matter? No, not really, he is still a nimrod and so is Truss.

[Peetwo]

P2,
(1) Was there a part 3 ?  The end of pt-2 is abrupt.
(2) Have you any video of the additional ATSB brief that was to have been at 12:30pm ?

Sorry "V" cut Pt 2 short because it went back to other issues i.e. Barnaby Joyce etc. The ATSB 12:30 brief was not included in the Parlview footage. However they have updated their MH370 investigation webpage with this:

Assistance to Malaysian Ministry of Transport in support of missing Malaysia Airlines flight MH370 on 7 March 2014 UTC

 
Investigation number: AE-2014-054
Investigation status: Active
 

• Underwater search
  
• Flight path analysis
  
• Search areas
  
• Overview
  

Underwater search
Download report released 3 Dec 2015
[PDF: 1.77MB]
 
 
Listen to this PDF
Alternate: [DOCX: 4.94MB]
 
MH370 - Definition of Underwater Search Areas

Released: 3 December 2015

Summary
This report provides an update to the MH370 search area definition, described in previous ATSB reports. For background information, please see the ATSB publications MH370 - Definition of underwater search areas, 18 August 2014 and Flight Path Analysis Update, 8 October 2014 under the tabs on this web page.

Analysis of available data has been ongoing since the search for MH370 commenced. Initial results assisted the search and rescue mission, and later refinements have formed the basis for the underwater search areas.

The Australian Defence Science and Technology (DST) Group conducted a comprehensive analysis of the available data. The analysis used models of the Inmarsat satellite communications (SATCOM) data and a model of aircraft dynamics. Recorded meteorological data (wind and air temperature) were also modelled in the analysis. The SATCOM model was calibrated using SATCOM data and flight data from B777 flights including previous flights of the accident aircraft.

Validation experiments were conducted to ensure that predictions aligned with actual flight data. The output of the DST Group analysis was a probability density function (PDF) defining the probable location of the aircraft’s crossing of the 6th arc. These results were then extrapolated to the 7th arc. The analysis indicated that the majority of solutions only contained one significant turn after the last recorded radar data. DST Group have written a book called Bayesian methods in the search for MH370 detailing the entire analysis.

Performance analysis by Boeing produced a series of achievable ranges, with time intervals, for different cruise altitudes. It was noted that maintaining a constant altitude of FL350 or higher gave range values that closely matched the region on the arc corresponding to the DST Group analysis results. The DST Group and Boeing results were obtained independently and it is significant that they were in general agreement.

In contrast to the series of data points that were recorded from the SATCOM system, only the following indirect information was available to assist the ATSB in determining the end-of-flight scenario and therefore determine a search area width:

• probable aircraft systems status
  
• simulator results
  
• review of previous accidents
  
• glide distance.
  

The original ATSB underwater search area definition report published in August 2014 identified a width of 20 NM behind the arc and 30 NM forward of the arc as the priority search area width. This primary priority width has been adjusted to make it symmetrical about the arc (20 NM on both sides). The ATSB has also defined and prioritised additional search area widths.

The probability distribution of the location of the aircraft is shown in Figure 1.

Figure 1: Probability distribution of the location of MH370
Ongoing work:
Any further evidence that becomes available, and may be relevant to refining the search area,will be considered.
 

• Bayesian Methods in the Search for MH370 by Defence Science and Technology Group, Australia. This analysis has informed the ATSB’s latest report, MH370 – Definition of Underwater Search Area.
  

Download report released 3 Dec 2015
[PDF: 1.77MB]
 
 

Any enquiries in respect of the ongoing investigation should, in the first instance, be directed to:
Malaysian Annex 13 Safety Investigation Team
Email: MH370SafetyInvestigation@mot.gov.my
 
General details
Date:
07 Mar 2014
 
Investigation status:
Active
 
Time:
1722 UTC
 
Investigation type:
External Investigation
 
Location   (show map):
Southern Indian Ocean
 
Occurrence type:
Missing aircraft
 
State:
International
 
Occurrence class:
Technical
 
Release date:
03 Dec 2015
 
Occurrence category:
Technical Analysis
 
Report status:
Pending
 
Highest injury level:
Fatal
 
Expected completion:
Jun 2016
 
 
Aircraft details
Aircraft model:
777-200ER
 
Aircraft registration:
9M-MRO
 
Operator:
Malaysian Airlines
 
Type of operation:
Air Transport High Capacity
 
Sector:
Jet
 
Departure point:
Kuala Lumpur, Malaysia
Destination:
Beijing, China
 
 

 


Last update 03 December 2015

MTF..P2

[Brock McEwen]

Another MH370 search audit, another set of gaping holes in the official story. Comparative analysis of 9 drift studies:

https://twitter.com/Brock_McEwen/sta...35285801246720

Coles Notes verdict on official claims flaperon "vindicates" current search zone: chaff.

[Brock McEwen]

FYI, here's the ERRONIOUS version of the GEMS report that caused the ATSB to, however unwittingly (...) misdirect attention to Indonesian shores:

https://drive.google.com/open?id=0B-r3yu...TNobFRxeVk

Took me twelve months - and invocation of Australia's FOI Act - to cajole this mere snippet out of them. Date-stamped Dec.1, 2015, so, you know, BRIMMING with authenticity.

[Peetwo]

FYI, here's the ERRONIOUS version of the GEMS report that caused the ATSB to, however unwittingly (...) misdirect attention to Indonesian shores:

https://drive.google.com/open?id=0B-r3yu...TNobFRxeVk

Took me twelve months - and invocation of Australia's FOI Act - to cajole this mere snippet out of them.  Date-stamped Dec.1, 2015, so, you know, BRIMMING with authenticity.

Thank you for that Brock...

Here are the individual pages for ease of viewing:









MTF..P2

 

[Peetwo]

FYI, here's the ERRONIOUS version of the GEMS report that caused the ATSB to, however unwittingly (...) misdirect attention to Indonesian shores:

https://drive.google.com/open?id=0B-r3yu...TNobFRxeVk

Took me twelve months - and invocation of Australia's FOI Act - to cajole this mere snippet out of them.  Date-stamped Dec.1, 2015, so, you know, BRIMMING with authenticity.

Thank you for that Brock...

Here are the individual pages for ease of viewing:








Here is a link for Brock's latest MH370 research paper - MH370 Drift Studies Comparative Analysis

MTF...P2

[P7_TOM]

I believe Master McEwan is to be, once again, congratulated.  Not for solving the riddle; but for logic, pragmatism and a honest effort to balance all against reason, logic and mathematical probability.  

On a more personal level I applaud the lack of egocentric behaviour which several academics seem to need in order to pooh-pooh each others pet theory; without having anymore proof to support theory than the next man or the fools in the market place.  

Anyway – thank you Brock for the effort, the research and the unfailing humour.

Cheers P7.

Brock McEwen Wrote: [/url]FYI, here's the ERRONIOUS version of the GEMS report that caused the ATSB to, however unwittingly (...) misdirect attention to Indonesian shores:


[url=https://drive.google.com/open?id=0B-r3yuaF2p72bDhUVTNobFRxeVk]https://drive.google.com/open?id=0B-r3yuaF2p72bDhUVTNobFRxeVk

Took me twelve months - and invocation of Australia's FOI Act - to cajole this mere snippet out of them.  Date-stamped Dec.1, 2015, so, you know, BRIMMING with authenticity.

Thank you for that Brock...

Here are the individual pages for ease of viewing:








Here is a link for Brock's latest MH370 research paper - MH370 Drift Studies Comparative Analysis

[Peetwo]

P2,
(1) Was there a part 3 ?  The end of pt-2 is abrupt.
(2) Have you any video of the additional ATSB brief that was to have been at 12:30pm ?

Sorry "V" cut Pt 2 short because it went back to other issues i.e. Barnaby Joyce etc. The ATSB 12:30 brief was not included in the Parlview footage. However they have updated their MH370 investigation webpage with this:

Assistance to Malaysian Ministry of Transport in support of missing Malaysia Airlines flight MH370 on 7 March 2014 UTC

 
Investigation number: AE-2014-054
Investigation status: Active
 

• Underwater search
  
• Flight path analysis
  
• Search areas
  
• Overview
  

Underwater search
Download report released 3 Dec 2015
[PDF: 1.77MB]
 
 
Listen to this PDF
Alternate: [DOCX: 4.94MB]
 
MH370 - Definition of Underwater Search Areas

Released: 3 December 2015

Summary
This report provides an update to the MH370 search area definition, described in previous ATSB reports. For background information, please see the ATSB publications MH370 - Definition of underwater search areas, 18 August 2014 and Flight Path Analysis Update, 8 October 2014 under the tabs on this web page.

Analysis of available data has been ongoing since the search for MH370 commenced. Initial results assisted the search and rescue mission, and later refinements have formed the basis for the underwater search areas.

The Australian Defence Science and Technology (DST) Group conducted a comprehensive analysis of the available data. The analysis used models of the Inmarsat satellite communications (SATCOM) data and a model of aircraft dynamics. Recorded meteorological data (wind and air temperature) were also modelled in the analysis. The SATCOM model was calibrated using SATCOM data and flight data from B777 flights including previous flights of the accident aircraft.

Validation experiments were conducted to ensure that predictions aligned with actual flight data. The output of the DST Group analysis was a probability density function (PDF) defining the probable location of the aircraft’s crossing of the 6th arc. These results were then extrapolated to the 7th arc. The analysis indicated that the majority of solutions only contained one significant turn after the last recorded radar data. DST Group have written a book called Bayesian methods in the search for MH370 detailing the entire analysis.

Performance analysis by Boeing produced a series of achievable ranges, with time intervals, for different cruise altitudes. It was noted that maintaining a constant altitude of FL350 or higher gave range values that closely matched the region on the arc corresponding to the DST Group analysis results. The DST Group and Boeing results were obtained independently and it is significant that they were in general agreement.

In contrast to the series of data points that were recorded from the SATCOM system, only the following indirect information was available to assist the ATSB in determining the end-of-flight scenario and therefore determine a search area width:

• probable aircraft systems status
  
• simulator results
  
• review of previous accidents
  
• glide distance.
  

The original ATSB underwater search area definition report published in August 2014 identified a width of 20 NM behind the arc and 30 NM forward of the arc as the priority search area width. This primary priority width has been adjusted to make it symmetrical about the arc (20 NM on both sides). The ATSB has also defined and prioritised additional search area widths.

The probability distribution of the location of the aircraft is shown in Figure 1.

Figure 1: Probability distribution of the location of MH370
Ongoing work:
Any further evidence that becomes available, and may be relevant to refining the search area,will be considered.
 

• Bayesian Methods in the Search for MH370 by Defence Science and Technology Group, Australia. This analysis has informed the ATSB’s latest report, MH370 – Definition of Underwater Search Area.
  

Download report released 3 Dec 2015
[PDF: 1.77MB]
 
 

Any enquiries in respect of the ongoing investigation should, in the first instance, be directed to:
Malaysian Annex 13 Safety Investigation Team
Email: MH370SafetyInvestigation@mot.gov.my
 
General details
Date:
07 Mar 2014
 
Investigation status:
Active
 
Time:
1722 UTC
 
Investigation type:
External Investigation
 
Location   (show map):
Southern Indian Ocean
 
Occurrence type:
Missing aircraft
 
State:
International
 
Occurrence class:
Technical
 
Release date:
03 Dec 2015
 
Occurrence category:
Technical Analysis
 
Report status:
Pending
 
Highest injury level:
Fatal
 
Expected completion:
Jun 2016
 
 
Aircraft details
Aircraft model:
777-200ER
 
Aircraft registration:
9M-MRO
 
Operator:
Malaysian Airlines
 
Type of operation:
Air Transport High Capacity
 
Sector:
Jet
 
Departure point:
Kuala Lumpur, Malaysia
Destination:
Beijing, China
 
 

 


Last update 03 December 2015

Update - Clarification

MH370 - Definition of Underwater Search Areas



Update: 10 December 2015

The ATSB has issued an update to clarify its recently released report MH370 - Definition of Underwater Search Area.

The update establishes that the ‘power loss’ mentioned on page 9 occurring between 17:07:48 and 18:03:41 was referring to the Satellite Data Unit (SDU) only.  The SDU did not respond to an automatic interrogation from the Ground Earth System (GES) at 18:03:41 UTC, although it resumed working at 18:25:27.

MTF..P2

[Peetwo]

Recent analysis/review, on Duncan Steel's website, by members of the IG regarding the ATSB 3 December 2015 released document - titled MH370 - Definition of Underwater Search Areas & DSTG analysis :

Comments and Questions Regarding the ATSB Report on MH370 of 3 December 2015 

Response to the ATSB Report and DSTG Book on MH370

Richard Godfrey and Victor Iannello
9th December 2015

 
Introduction
The Australian Transport Safety Bureau (ATSB) published an update to their report entitled “MH370 – Definition of Underwater Search Areas” on 3rd December 2015. At the same time, the Australian Defence Science and Technology Group (DSTG; formerly the DSTO) through the ATSB made available a book entitled “Bayesian Methods in the Search for MH370”. Both may be downloaded as PDFs (1.76 MB and 8.76 MB respectively) via this webpage.

At first sight, the search area centred on a point located at 38.0S 88.4E aligns very well with the end point published by the IG (over 14 months ago, on 26th September 2014; see here also) at 37.71S 88.75E. In fact, these two points are only 24 NM apart.

However, when one digs a little deeper, there are obvious flaws in the Bayesian approach adopted by the DSTG team and the belated confirmation of the IG end point by the DSTG is more due to error than design. There appears to be a fundamental disconnect between the mathematics employed and the constraints imposed on possible paths based on the aircraft dynamics and satellite communication data. In this brief post we summarise how and why this is so.

Bayesian approach
The BFO and BTO data are stochastic in nature, so assigning random variables and calculating probability density functions for the derived end point from paths based on the uncertainty of these variables seems reasonable, especially if other constraints are considered such as human factors and aircraft performance characteristics.

The path travelled, however, was most likely not stochastic: there was a deterministic reason for whatever path the plane took, be it human intention or a particular failure mode. And that particular path could have a very low probability if it is just one of many possible random paths that are generated in the way the DSTG researchers generated their possible paths.

Bias toward straight paths and against curved paths
The DSTG posterior distribution has a high incidence of straight paths, which peaks the end point distribution around 38S. In fact, if all speeds and turn times are equally probable, the distribution should be much flatter. By virtue of the way the DSTG generate paths using random manoeuvres and random changes in heading and speed, curved paths (which require more turns) are not represented as often in the posterior distribution.

This bias for straight paths can be seen in Chapter 7 of the DSTG book. Figures 7.2 and 7.4 show paths for which the BTO and BFO are ignored completely. There is a hot spot for the end point in Oman, corresponding to a straight flight starting at 18:02 and proceeding northwest.

The assumption made, then, is that the plane flew straight between manoeuvres, so a flight with few manoeuvres flies relatively straight. This produces a bias in the analysis in favour of straight paths and against curved paths.

Bias toward faster speeds and against slower speeds
In the DSTG study, the speeds after manoeuvres are chosen to be randomly distributed between Mach 0.73 and Mach 0.84 based on fuel considerations. In this brief section we indicate why the choice of lower speed limit is erroneous if fuel consumption is the only consideration.

At FL350 and DTisa=0, these Mach speeds corresponds to True Air Speeds (TAS) of 421 knots and 484 knots respectively. At DTisa = 10K, the TAS range is 430 to 495 knots.

The Holding Speed of an aircraft is defined as the speed at which fuel flow rate is at its minimum, for any specified altitude. Over the interval from 18:28 to fuel exhaustion the average weight of the plane is about 192.3 tonnes. Using this average as a constant weight throughout that interval, at Holding Speed at FL200, and with DTisa = 0, the appropriate Indicated Air Speed (IAS) is 213 knots, which corresponds to Mach 0.47 and a TAS of 288 knots. At DTisa = 10K, Mach 0.47 corresponds to a TAS of 293 knots.

There is therefore a fundamental error made in setting a lower limit of TAS equal to 421 knots when speeds of around 288 knots would have sufficient endurance if the aircraft flew at a level around FL200.

Because fuel considerations allow lower speeds than M0.74, the DSTG model has an inherent bias toward faster speeds.

Cost Index
The Cost Index (CI) has finally been made public (a request for its publication was made in September 2014) and we are told that the flight was planned on the basis of a CI of ECON 52. The resulting MH370 Flight Path Model V16.0 is published elsewhere and shows an end point of 38.4S 87.7E.

Radar Data
The DSTG Bayesian approach is based on a prior defined by the Malaysian Military Primary Radar at 18:01 (penultimate 10-second radar capture).

The single capture from the Malaysian Military Primary Radar at 18:22 was not used by the DSTG because it is thought likely to be less accurate, near the radar system’s maximum range. However, this single radar capture has been shown to align with the satellite data a few minutes later.

The Malaysian authorities’ previous public releases of their Military Primary Radar data is not consistent with the Malaysian Military Primary Radar available to the team at DSTG, as it shows a detailed radar trace with a large number of data points after 18:01:49 up to 18:22:12. For example, see the photograph below.

We request the following:

1. Publication the 10-second Primary Radar data from 16:42:27 to 18:01:49.
2. An explanation of the source of the Primary Radar trace between 18:01:49 and 18:22:12 (as shown above) and whether the Malaysian authorities have made these radar-determined positions available to the ATSB and the DSTG.

BFO Bias
The BFO bias was found by the DSTG researchers to have a geographic dependency, but it was not possible for them to determine the cause. A geographic dependency can be ruled out, as the laws of physics do not change with location and time. As this uncertainty in the bias causes a large uncertainty in the overall BFO measurement, it needs to be better understood.

Conclusion
In summary, the recent DSTG report presents a generalized, Bayesian method to prioritize the search zone. Although the ATSB is using this report as justification of its current search area, the alignment between the new results and previous results are a result of an inherent bias towards straight, high speed paths. More generalized methods would allow a larger range of end points. This bias should be acknowledged.

MH370 Flight Path Model version 16

Richard Godfrey
9th December 2015

 
I have updated my MH370 Flight Path Model to include a simulation of the Cost Index (CI) at ECON 52, now that the CI has been made available in the latest ATSB report. This updated model is labelled as version 16.0, the preceding version 15.1 having been described here.

The model version 16.0 (Excel spreadsheet, 2.5 MB) may be downloaded by clicking here.
I retained a late final major turn (FMT) starting at 18:37:24 and 15.6 NM before the waypoint IGOGU.

I also retained a step climb to 39,000 feet.

The resultant end point is located at 38.4S 87.7E.

Update 10th December:

Version 16.1 of the Flight Path Model is now available here. Version 16.0 entailed a constant speed being used between ping arcs 6 and 7, whereas a deceleration would be expected (a value of -0.315 knots per second has now been used here in v16.1, in line with Brian Anderson’s analysis).

The resultant end point is now 38.2S 88.0E.

Thanks to Brock McEwen for pointing this out.

Misinterpretation of Aircraft Control Modes in the DSTG Book on MH370

Brian Anderson
14th December 2015 

 

1. Introduction 
   
   

The Australian Transport Safety Bureau (ATSB) published an update to their report entitled “MH370 – Definition of Underwater Search Areas” on 3rd December 2015. At the same time, the Australian Defence Science and Technology Group (DSTG; formerly the DSTO) through the above ATSB webpage made available a book entitled “Bayesian Methods in the Search for MH370” (hereafter, DSTG book).

Some of the statements made by the DSTG authors warrant further attention and explanation. Specifically, the statements made in relation to control angles and headings in 6.3.1 thru 6.3.5 of the DSTG book are inaccurate and misleading, although the way that these factors are incorporated in the analysis may not change the result of the study.
In this post I explain how and why those statements are misleading, why the errors made might be of fundamental importance in the search for MH370, and indicate what could and should be done in terms of correcting the analysis. The intent here is simply to identify mistakes made in order to assist the official search teams.
 

1. Lateral Control Functions
   
   

All the descriptions I have read of the roll functions for the B777 aircraft – and probably the Continental B777 Training Manual is the most detailed on the subject – indicate that magnetic parameters are calculated with reference to a look-up table of magnetic declination by using inputs of angles, velocities and position derived from the Inertial Navigation System (INS) and earth references (as opposed to the magnetic parameters being directly measured). For example:

Ref: section 34-20-00, page 41 of the Continental Manual (page 1839 of 3328)

Magnetic Heading And Magnetic Track
Rotational rates and linear accelerations go to the rotate accelerations to earth reference function. The rotate accelerations to earth reference function calculates accelerations in relation to the earth. The accelerations in relation to the earth go to the velocities integrator. The velocities integrator calculates velocities. The velocities go to the position integrator and the calculate magnetic parameters function. The position integrator calculates airplane position.

The calculations described above are performed in the ADIRS – ADIRU system, shown in block diagram form in section 34-20-00, page 43 of the Continental Manual (page 1841 of 3328), as below: .
The roll control functions are described as follows:
  
Heading/Track Hold
In this mode, the airplane holds either heading (HDG) or track (TRK).
If the HDG/TRK display on the MCP shows TRK, the airplane holds track.
If the HDG/TRK display on the MCP shows HDG, the airplane holds heading. 

Heading/Track Select
In this mode, the airplane turns to the heading or track that shows in the heading/track window.
If the HDG/TRK display shows HDG, the airplane goes to and holds the heading that shows in the heading/track window.
If the HDG/TRK display shows TRK, the airplane goes to and holds the track that shows in the heading/track window. 

It is not explicitly stated in the manual whether the aircraft will (at least over a period of some hours) hold the heading or the track if the heading display is in Norm (i.e. displaying a magnetic heading, and thus follow a curved path).
(With regard to the distinction between the terms “Heading” and “Track”, please see the addendum at the end of this post.)

Further evidence that magnetic angles are in fact calculated and not measured can be ascertained from Aero Quarterly (issue: Qtr 04/09), as published by Boeing, discussing Correcting the Effects of Magnetic Variation, and emphasizing the importance of airlines updating their inertial reference systems to the latest magnetic variation (MagVar) tables in order to avoid potentially hazardous magnetic heading-related navigation errors.

The Heading- and Track-Select functions serve only to turn the aircraft onto a new Heading. Once that Heading has been acquired the roll control functions serve to maintain the Heading or the Track automatically.

Considering the possibility that the Heading or Track may be displayed with reference to True North [True], or Magnetic North [Norm], there are therefore four possible combinations of Heading and Track Hold that might ultimately determine the path of the aircraft, as follows:

(i) TRK Hold [True]
In this mode the track of the aircraft is maintained constant with respect to True North, and small instantaneous adjustments to the aircraft heading are performed to compensate for wind vectors so as to achieve this. The resulting flight path describes a loxodrome.

(ii)        HDG Hold [True]
In this mode the heading of the aircraft is maintained constant with respect to True North. No adjustments to the aircraft heading are performed to compensate for wind vectors. The resulting flight path would describe a loxodrome in zero wind conditions, but is otherwise continuously modified by wind vectors.

(iii)       TRK Hold [Norm]
In this mode the track of the aircraft is maintained constant with respect Magnetic North, and small instantaneous adjustments to the aircraft heading are performed to compensate for wind vectors to achieve this. The resulting path will be curved. Since the magnetic heading is calculated in the ADIRS – ADIRU system the aircraft heading (with respect to the earth) must be continually modified and updated by incorporating the declination obtained from the MagVar tables relating to the current aircraft position, and the wind vector.

(iv)       HDG Hold [Norm]
In this mode the heading of the aircraft is maintained constant with respect to Magnetic North. No adjustments to the aircraft heading are performed to compensate for wind vectors. The resulting path will be curved as in (iii) above in zero wind conditions, and is otherwise continually modified by wind vectors. Again, the aircraft heading (with respect to the earth) must be continually modified and updated by incorporating the declination obtained from the MagVar tables relating to the current aircraft position.
 

1. Lateral Navigation
   
   

Lateral Navigation (LNAV) is a specific control mode whereby the aircraft typically follows a series of waypoints previously stored as a flight plan in the Flight Management System (FMS). The track followed by the aircraft between waypoints is (a segment of) a Great Circle. The aircraft heading is continuously adjusted for wind vectors to maintain this track.

Waypoints can be defined in many ways. They are not limited to predefined Instrument Flight Rules (IFR) waypoints, and can be entered into the FMS (more specifically, the Control Display Unit, or CDU) to modify the flight plan at any time. For example it is possible to describe a waypoint simply as a set of latitude and longitude coordinates (such as “N071.2E0953.15”, which represents a waypoint at  N7° 1.2’ E95° 3.15’, and is displayed as N07E095).

Section 6.3.5 of the DSTG book states, in reference to the LNAV control mode:

“Expert advice indicates that if the autopilot system is operating in lateral navigation mode and it reaches the final programmed waypoint, then it reverts to the previously selected heading hold mode.” 

This statement is at variance with the description of LNAV operation in the Honeywell B777 FMS Manual, and with the description found in a variety of other B777 FMS references.

The Honeywell description of the LNAV action after overflying the last programmed waypoint is this:

“. . . DISCONTINUITY is displayed in the scratchpad, and the aircraft maintains its existing track.” 

Other references state:

“LNAV maintains current heading when passing the last active route waypoint.” 

The different terminology used in different references (Track vs Heading) may simply be one of common usage of the terms when describing an instantaneous point in flight (i.e. the instant that the discontinuity occurs).

It is interesting to note, from the Honeywell manual, that:

“Only the active waypoint course can be referenced to magnetic north because the ADIRU can provide magnetic variation only for present position.”

This would suggest that the course followed after passing the last waypoint, which by definition cannot be an active waypoint course, cannot therefore be referenced to magnetic north.
 

1. How is this relevant
   

Considering the aircraft path southwards from a position in the northwest of the Malacca Strait:

(i) If this path was being managed in LNAV mode (with or without manual input), then the final turn south must have been at or about a predetermined waypoint, and furthermore the track from that point must be a Great Circle to another waypoint that had previously been manually entered into the FMS via the CDU. Clearly, manual input of at least two waypoints is therefore necessary at some time before reaching the final turn in the Malacca Strait. After overflying that final waypoint (if indeed it was actually reached), then the aircraft would be expected to continue on the same track. At that point the track may become a loxodrome.

(ii) There is no evidence to exclude the possibility of some flight manoeuvres towards the end of the track in the Malacca Strait, which would have delayed the commencement of the flight south. For example it is entirely possible that the aircraft completed an orbit of greater than 360 degrees, perhaps 460 degrees even, before proceeding south. Any delay or manoeuvres such as this can be shown to still fit the available satellite data, in particular an intercept with an arc meeting the BTO at 19:41 UTC. However it seems most unlikely that such manoeuvres would have been manually entered in to the CDU to become an active flight plan.

(iii) An alternative to the final turn south being a turn at a waypoint is the possibility that the turn was initiated manually using the Heading- or Track-Select controls. After selection the aircraft rolls onto the desired heading or track, and then holds the selection, as described in 2(iii) and 2(iv) above. (Note that this selection also effectively overrides the LNAV function.) It is therefore necessary to consider flight paths consistent with these control modes.

(iv) We do not know the control mode in use at the time of the final turn south. However, one might be biased toward Norm (magnetic reference) rather than True, since Norm is the de facto standard for most flight manoeuvres where these control modes would be used. For example, virtually all tracks and headings described on aviation navigation charts are referenced to Magnetic North, as are virtually all instructions from Air Traffic Control (ATC).

(v) While TRK Hold [True] would result in a relatively straight path (a loxodrome) from the final turn, each of the other three control modes would result in curved paths, in fact curving significantly eastwards as the flight progressed, due to increasing westerly winds at more southerly latitudes, and the magnetic declination increasing more rapidly.

(vi) The DSTG analysis seems heavily biased toward straight paths after the final turn south, and it is therefore not surprising that a “hot spot” at about 38 degrees south results. On the basis that it seems equally likely that curved paths may have been followed, or indeed the turn south commenced further to the NW in the Malacca Strait, or occurred at a later time, it is of concern that termination points further NE on the 7th arc have not been shown to be viable, and perhaps even equally probable, given our lack of knowledge of the aircraft control modes in operation during MH370’s flight southwards.

(vii) It can be shown that curved paths, such as might result from control modes described in 4 (ii), (iii) and (iv), can also fit the Inmarsat-derived data, and end on the 7th arc, but further to the northeast on that arc than the “hot spot” indicated in the DSTG book and on the cover of the latest ATSB report update. Such curved paths, however, are not at constant speed. Speed variations, and in particular significant slowing of the aircraft towards the end of the flight, are necessary in order to fit the Inmarsat data with these paths.

(viii) While TRK/HDG Hold [Norm] have their place in managing aircraft navigation – and in particular in respect of standard procedures, navigation chart information and under instruction from ATC – the requirement in these situations is for only relatively short times and relatively short distances. In such situations the magnetic declination does not change significantly and the resulting aircraft azimuth remains essentially fixed.

Furthermore, that azimuth would be precisely the same whether the displayed track or heading was referenced to Magnetic or True North. In contrast, maintaining TRK/HDG Hold [Norm] over lengthy times or long distances has absolutely no value. The fact that either of these two modes may have become the default lateral control mode over something like the last six hours of the flight of MH370 serves only to compound the problem of identifying the final resting place.
 

1. Conclusion
   

The analysis in the DSTG book should be reviewed after correcting the misinterpretation of the aircraft control modes as presented in Chapter 6 of that book.

Also of interest is this article from Planetalking today:

New details about MH370 search come to light

Ben Sandilands | Dec 17, 2015 1:22PM |

Just a tiny part of the seventh arc search zone

New insights into the search for missing flight MH370, and what happens the moment the jet is found, were explained at a briefing for members of the Surveying and Spatial Sciences Institute in Perth recently.

Paul Kennedy, MH370 Search Project Director, Fugro Survey, took the audience through the same induction video shown to recruits before they joined the three vessels that are sonar scanning the priority zones in the southern Indian Ocean that are believed most likely to contain the sunk wreckage of the jet.

This YouTube of his presentation gives but a distant low resolution view of Mr Kennedy’s graphics, but it is what he says that is of interest.

At the outset he reminds the audience that the so called seventh arc along which the priority zones are located is different from the earlier arcs which represented places MH370 could have been when it send automated pings to an engine performance monitoring site at Rolls-Royce in Derby via an Inmarsat satellite and ground stations.

This last and unexpected transmission from the jet was initiated by the failure of its engine generated electrical supply and the automated deployment of a ram air turbine that popped out of the fuselage to generate emergency power as the jet fell toward the sea.

With the help of audience members Mr Kennedy unrolled a large scroll of the seabed in the seventh arc priority zone that stretched across the room and out one door which had mapped its features and their depths with sufficient accuracy to prevent deep sea ‘tow fish’ or sonar scanning platforms being towed into the side of underwater obstacles like volcanic craters while surveying the terrain from a height of around 100 metres.

On that map MH370 would only have been a small dot, and it is of course covered in dots, and often convoluted terrain, with deep fissures and troughs and sea mounts and cliffs.

Mr Kennedy said the Boeing 777 would only have subtended half a millimeter in size on the waist high scroll unfolded across the room.

He explained that the raw data was not just being recorded on the search vessels in real time, but being uploaded to ‘cloud’ computers via specially targeted reception beams directed to them from satellites to provide a high bandwidth tunnel.

That data was being simultaneously but separately reviewed “by multiple sets of eyes in Australia and the US”. (He made no reference to Malaysia in relation to the uploads.)
This was occurring in sea states in which peak waves had been recorded as 16.5 metres at their highest, but more commonly of around 11 metres , and often around 6-8 metres.

(There is a great deal of information in the presentation on the working environment, and the health and safety precautions taken on ‘swings’ that included around 13 days total sailing time from Fremantle to reach and return from the priority zones).

Mr Kennedy said there had been prolonged periods when the search vessels had to maintain a heading into winds of around 150 kmh, unable to turn to either side in the sea states that prevailed. He said the crews working shifts covering continuous operations were holding onto the sides of their bunks while trying to sleep, causing considerable fatigue toward the end of periods of duty.

He said the seabed search includes ‘nightmare’ zones when towering complex cliffs and pot holes within volcanic craters may hide the wreckage of the Malaysia Airlines 777-200ER .

The Norwegian Hugin autonomous underwater vehicle or AUV was being used to explore the otherwise impossible to scan wrinkles which could contain parts of MH370. This had included descending deep into features inside volcanic cones, and continued to look into a 200 kilometres long 70 degrees slope that was around 1000 metres in height above the adjacent sea floor.

This slope contained ledges and fissures that the regular tow fish could not look into.
By coincidence on the first anniversary of the disappearance of MH370, a towfish had come across an unnatural set of objects which looked as though they could have come from the missing flight.

However when it was studied in closer detail by the AUV it was found to be an unchartered, and so far, untraced shipwreck.

Mr Kennedy said that some maritime detective work had established that the anchor was probably made around 1820. The actual wooden ship had disappeared over time, and all that was left was the anchor, the ship’s bell, a spread of metal nails and fixtures, and a large sea chest.

What happens when MH370 is found?
Once it is clear that MH370 has been found the satellite data links to the vessel will be shut down and immediate steps made to notify the next of kin of the 239 people on board the jet.

Mr Kennedy’s brief comments about this made it clear that the search intends, commendably, to ensure that those who lost their loved ones on MH370 will be first to learn that the jet and thus their final resting places, have been found.

They will not learn of it through the media. (However it is highly probable that once next of kin have learned of a discovery, word will reach the media, possibly before but most likely only shortly before, an official media briefing is called. These are this reporter’s observations, not Mr Kennedy’s).

Other revelations in the briefing include a sea floor duration of up to 32 hours for the AUV and a very important checking process that validates the performance of the equipment being used in the priority search area. The AUV doesn’t upload in real time, but sends tracking information to the surface, and on recovery after a dive then downloads its data.

Boeing has set up a test and calibration field on the sea floor that each vessel passes through on its way out of and into Fremantle with each tour of duty.

This field includes objects that would correspond to parts of the sunk wreckage of MH370, such as the engines and other heavy components, and replicates their expected resolution to sonar scanning tow fish.

The scientist who made this YouTube record of the presentation said,
“This is incredibly important as when you do surveying you must have confidence that all the work you have done is verified.

“If upon returning to port and doing a closing check on the way back, the items in the test field were unable to be sighted in the detail they had expected this would not only detect a fault with the equipment, but almost certainly void ALL of the past several weeks of deep ocean scanning carried out.

“You wouldn’t know if your equipment stopped working at 100 percent two weeks or 2 hours ago!

“So doing a return scan over the items off the coast of WA would be a great relief to all of the crew on board that all their work is valid.”

MH370 vanished early on a flight between Kuala Lumpur and Beijing on 8 March 2014, when the jet was over the Gulf of Thailand and about to enter air space under Vietnamese control.

Here is the presentation on Youtube, definitely well worth viewing...

MTF..P2

[Peetwo]

New details about MH370 search come to light

Ben Sandilands | Dec 17, 2015 1:22PM |

Just a tiny part of the seventh arc search zone

New insights into the search for missing flight MH370, and what happens the moment the jet is found, were explained at a briefing for members of the Surveying and Spatial Sciences Institute in Perth recently.

Paul Kennedy, MH370 Search Project Director, Fugro Survey, took the audience through the same induction video shown to recruits before they joined the three vessels that are sonar scanning the priority zones in the southern Indian Ocean that are believed most likely to contain the sunk wreckage of the jet.

This YouTube of his presentation gives but a distant low resolution view of Mr Kennedy’s graphics, but it is what he says that is of interest.

At the outset he reminds the audience that the so called seventh arc along which the priority zones are located is different from the earlier arcs which represented places MH370 could have been when it send automated pings to an engine performance monitoring site at Rolls-Royce in Derby via an Inmarsat satellite and ground stations.

This last and unexpected transmission from the jet was initiated by the failure of its engine generated electrical supply and the automated deployment of a ram air turbine that popped out of the fuselage to generate emergency power as the jet fell toward the sea.

With the help of audience members Mr Kennedy unrolled a large scroll of the seabed in the seventh arc priority zone that stretched across the room and out one door which had mapped its features and their depths with sufficient accuracy to prevent deep sea ‘tow fish’ or sonar scanning platforms being towed into the side of underwater obstacles like volcanic craters while surveying the terrain from a height of around 100 metres.

On that map MH370 would only have been a small dot, and it is of course covered in dots, and often convoluted terrain, with deep fissures and troughs and sea mounts and cliffs.

Mr Kennedy said the Boeing 777 would only have subtended half a millimeter in size on the waist high scroll unfolded across the room.

He explained that the raw data was not just being recorded on the search vessels in real time, but being uploaded to ‘cloud’ computers via specially targeted reception beams directed to them from satellites to provide a high bandwidth tunnel.

That data was being simultaneously but separately reviewed “by multiple sets of eyes in Australia and the US”. (He made no reference to Malaysia in relation to the uploads.)
This was occurring in sea states in which peak waves had been recorded as 16.5 metres at their highest, but more commonly of around 11 metres , and often around 6-8 metres.

(There is a great deal of information in the presentation on the working environment, and the health and safety precautions taken on ‘swings’ that included around 13 days total sailing time from Fremantle to reach and return from the priority zones).

Mr Kennedy said there had been prolonged periods when the search vessels had to maintain a heading into winds of around 150 kmh, unable to turn to either side in the sea states that prevailed. He said the crews working shifts covering continuous operations were holding onto the sides of their bunks while trying to sleep, causing considerable fatigue toward the end of periods of duty.

He said the seabed search includes ‘nightmare’ zones when towering complex cliffs and pot holes within volcanic craters may hide the wreckage of the Malaysia Airlines 777-200ER .

The Norwegian Hugin autonomous underwater vehicle or AUV was being used to explore the otherwise impossible to scan wrinkles which could contain parts of MH370. This had included descending deep into features inside volcanic cones, and continued to look into a 200 kilometres long 70 degrees slope that was around 1000 metres in height above the adjacent sea floor.

This slope contained ledges and fissures that the regular tow fish could not look into.
By coincidence on the first anniversary of the disappearance of MH370, a towfish had come across an unnatural set of objects which looked as though they could have come from the missing flight.

However when it was studied in closer detail by the AUV it was found to be an unchartered, and so far, untraced shipwreck.

Mr Kennedy said that some maritime detective work had established that the anchor was probably made around 1820. The actual wooden ship had disappeared over time, and all that was left was the anchor, the ship’s bell, a spread of metal nails and fixtures, and a large sea chest.

What happens when MH370 is found?
Once it is clear that MH370 has been found the satellite data links to the vessel will be shut down and immediate steps made to notify the next of kin of the 239 people on board the jet.

Mr Kennedy’s brief comments about this made it clear that the search intends, commendably, to ensure that those who lost their loved ones on MH370 will be first to learn that the jet and thus their final resting places, have been found.

They will not learn of it through the media. (However it is highly probable that once next of kin have learned of a discovery, word will reach the media, possibly before but most likely only shortly before, an official media briefing is called. These are this reporter’s observations, not Mr Kennedy’s).

Other revelations in the briefing include a sea floor duration of up to 32 hours for the AUV and a very important checking process that validates the performance of the equipment being used in the priority search area. The AUV doesn’t upload in real time, but sends tracking information to the surface, and on recovery after a dive then downloads its data.

Boeing has set up a test and calibration field on the sea floor that each vessel passes through on its way out of and into Fremantle with each tour of duty.

This field includes objects that would correspond to parts of the sunk wreckage of MH370, such as the engines and other heavy components, and replicates their expected resolution to sonar scanning tow fish.

The scientist who made this YouTube record of the presentation said,
“This is incredibly important as when you do surveying you must have confidence that all the work you have done is verified.

“If upon returning to port and doing a closing check on the way back, the items in the test field were unable to be sighted in the detail they had expected this would not only detect a fault with the equipment, but almost certainly void ALL of the past several weeks of deep ocean scanning carried out.

“You wouldn’t know if your equipment stopped working at 100 percent two weeks or 2 hours ago!

“So doing a return scan over the items off the coast of WA would be a great relief to all of the crew on board that all their work is valid.”

MH370 vanished early on a flight between Kuala Lumpur and Beijing on 8 March 2014, when the jet was over the Gulf of Thailand and about to enter air space under Vietnamese control.

Right said Fred -

Presumably feeling emboldened by the ATSB admission that MH370 suffered a power loss (see above posts & 3 December released report MH370 - Definition of Underwater Search Area ), Simon Gunson kicked off some lengthy commentary - see HERE - on Ben's article. To which Ben made this choc frog reply.. :

3
Ben Sandilands
Posted December 18, 2015 at 6:46 am | Permalink

Simon,

As I’ve mentioned previously many times, much of your concern about claimed radar data is based on believing unsubstantiated media echo chamber fabrications. It doesn’t reflect well on my profession, and I am deeply embarrassed by that, but certain high profile reporters invented sh*t which you keep putting in your sandwiches.

Put alongside the clumsy, and perhaps wilfully misleading variations in the official and amazingly variable narratives from KL you, I and everyone is entitled to be thoroughly annoyed.

But none of this helps us explain in detail your fire and decompression theory, and how it relates to a sequence of electrical events, some of which may be coincidental and thus unrelated which may tell us important things about the conduct of the flight.

This matrix of events and possibilities is the main reason why I have no coherent theory as to what happened to MH370 that I’d be prepared to defend.

There are too many uncertainties, and too high a risk of unknown factors, including some which may have been suppressed by the authorities, who didn’t seem to give a damn on the night the flight disappeared. (There is something really weird about the unresponsiveness of the airline and the authorities to the disappearance of a 777 FFS!)

I am disappointed but ought not be surprised by the current broader discussion (way wider than it is here) where basically it has became a slanging match between the supporters of various theories, all backed up by incomplete or totally missing data as the case may be.  

But of course as is typically the case Simon was not happy to let it slide and he continued to bang on until "V" stepped in at post #13:

13
Ventus45
Posted December 23, 2015 at 1:08 am | Permalink

Simon: you said:

“My own estimate is that the 7th Arc is offset 315nm closer to the satellite and MH370 flew further south sans detour.”

Please explain your reasoning for shortening the 7th arc radius (with the maths if possible).

14
Simon Gunson
Posted December 23, 2015 at 10:25 am | Permalink

Ventus45
Sorry my explanation was not very clear.

I am saying I believe the PERCEIVED 7th Arc is presently 315nm nearer to satellite than it actually is. In fact I am saying all Arcs were displaced nearer to satellite by BTO transmission bias errors.

As you probably understand BTO transmission delay is the unknown variable. The doubt was resolved by averaging BTO bias from samples pre take off.

If MH370 suffered electrical failure before 18:03 UTC then they cannot assume the BTO transmission bias before take off was same after problems.

In particular if electrical fire caused a fire to melt fuselage skin then decompression would subject avionics to chilling below -40degC which is minimum operating temp for most avionics associated with ACARS.

Chilling avionics reduces electrical resistance in metal, thereby shortens the signal path delay. This gives a pseudo impression that the BTO Arcs were closer to the satellite.

Methodology was quite crude simply generating an arc for satellite at 00:11 UTC passing thru impact co-ordinates calculated by China by reverse drift analysis (45.30S, 85.30E)= 315nm further out from current 7th Arc.

Remember if MH370 was hypoxic flight south after electrical fire then all fuel endurance assumptions are wrong too and MH370 could have flown further south.

My belief is that MH370 reached BITOD and turned back for Kuala Lumpur, then suffered fire in MEC and whilst trying to resolve this MH370 suffered decompression whilst pilots were distracted.

If there was failure to R & L Main AC transfer buses, then all AIMS shut down.
Autopilots kept working off Standby Transfer bus but post decompression Autopilots could only follow last magnetic heading they had. From this I extrapolate they flew a Rhumb line south.

Rhumb line would have curved east due to distortion of Earth’s magnetic field in SIO. The BFO data will be correct but to understand the BFO track mathematically you either have to have a plausible start point or work back from a finish point.

15
Ventus45
Posted December 23, 2015 at 12:22 pm | Permalink

Simon.

OK, I follow your line of reasoning now.

The BTO bias of minus 495679 micro sec calculated at Gate C1 at normal temps is basic to all of the ping ring calculations.

It has been taken almost as an “article of faith” by ATSB and the IG to be both stable and correct. If that is a wrong assumption, all arcs after 17:07utc could be off.
The problem of where MH-370 actually “went” comes back to the radar, the Penang turn, and in particular, the last radar hit at 02:22 local (18:22utc).

If “that” position can be “solidly” established, then the calculations for the next ping, only 5 minutes later, at 18:27utc could be verified from performance analysis.
But, unfortunately, the Malaysian Government refuses to release the raw radar data, supposedly for “security reasons”.

Without a “precision position for 18:22utc” we can not do a “sanity check” on the BTO Bias “in flight”. We are therefore left with the calculated Bias at Gate C1, and are left guessing as to whether or not it is “stable”.   

But even then Simon just had to have the last word :

16

Simon Gunson
Posted December 24, 2015 at 10:33 am | Permalink

Ventus45

Whether one believes in decompression or not, ponder this:
For the SDU to out of action from at least 18:03 (expected ACARS handshake) to 18:25 (AES log on) means both L&R Main AC transfer buses were unable to power the SDU.

This means the autopilot was working solely from the Standby Transfer Bus.

This bus will power the autopilot but not higher brain functions of the AIMS.

Without AIMS, MH370 could not have navigated turns through the Straits of Malacca. It is not an article of faith whether you believe in Decompression. No AIMS = no detour.

Having become predictive & repetitive that is where the discussion normally fizzles out..

However 2 days ago Fred weighed in with my nomination for the first POTW for 2016 :

17

Fred
Posted January 2, 2016 at 1:37 pm | Permalink

Simon,

Your theory of a fire within the aircraft’s Main Equipment Centre (MEC) and subsequent decompression is certainly worth exploring and may ultimately prove to be correct if the aircraft is ever found and useful data is recovered. The power interruption to the Satellite Data Unit (SDU) that occurred early in the flight does seem to be an indication that something was amiss. Finding out what caused that power interruption may well be the key to the sequence of events that followed. That said, I think it’s a little early to be making categorical conclusions based on the paltry evidence we have to date. As Ben said, “there are too many uncertainties and too high a risk of unknown factors”.

Some of your technical information is incorrect. First, the Airplane Information Management System (AIMS) is essentially the ‘brains’ of the B777. The system consolidates the processing for a number of aircraft systems and is essential to the operation of the aircraft. For redundancy purposes there are two identical AIMS cabinets within the MEC. Each AIMS cabinet has several separate DC power sources, for which there are several layers of backup in the event of a power failure. If all else fails, the AIMS cabinets will continue to be powered directly from the aircraft battery. AIMS will not shut down if AC power is lost to the Main AC buses.

Second, the B777 does not have a Honeywell Mark III Communications Management Unit (CMU), which you identified (on other websites) as the root cause of MH370’s disappearance. The equivalent function is performed by the Data Communications Management System (DCMS) within AIMS. The DCMS is incorporated within a Core Processor Module (CPM) within each AIMS cabinet. That does not rule out a fire originating within the CPM or elsewhere within one of the AIMS cabinets, but in the event of such a fire the DCMS functions should be taken over by the other AIMS cabinet.

I tend to think that a fire within the MEC would be more likely to occur within one of the Electrical Load Management System (ELMS) panels, also located within the MEC. The ELMS panels that service the left buses are on the left hand side of the MEC, close to the fuselage wall and adjacent to the crew oxygen bottles. If a fire did erupt in that area and subsequently compromised the oxygen system, the results would be catastrophic to say the least.

Finally, Penang was the nearest suitable airport that was available at the time the aircraft is believed to have turned back towards the Malaysian peninsular (Kota Bharu is closed at that time of night). It is not, therefore, unreasonable to assume that in a serious emergency the crew would have initiated a turn back towards Penang rather than Kuala Lumpur. They might well have programmed the Flight Management Computer (FMC) accordingly before becoming incapacitated. The aircraft’s final track would ultimately depend on what was entered into the FMC.    

Two choc frogs for Fred..


MTF..P2

Ps I wait with interest for Simon's reply & for his math on the shortening of the 7th Arc radius..

[Kharon]

Ben Sandilands: - “This matrix of events and possibilities is the main reason why I have no coherent theory as to what happened to MH370 that I’d be prepared to defend.

There are too many uncertainties, and too high a risk of unknown factors, including some which may have been suppressed by the authorities, who didn’t seem to give a damn on the night the flight disappeared. (There is something really weird about the unresponsiveness of the airline and the authorities to the disappearance of a 777 FFS!)

I am disappointed but ought not be surprised by the current broader discussion (way wider than it is here) where basically it has became a slanging match between the supporters of various theories, all backed up by incomplete or totally missing data as the case may be.”

Fred: - “It is not, therefore, unreasonable to assume that in a serious emergency the crew would have initiated a turn back towards Penang rather than Kuala Lumpur. They might well have programmed the Flight Management Computer (FMC) accordingly before becoming incapacitated. The aircraft’s final track would ultimately depend on what was entered into the FMC.”

The voices of calm thought and reasonable doubt expressed rationally.  Ventus 45, Brock and several are others quite happy to present a ‘scenario’, back it up with logic and data for discussion – all the while acknowledging that there is scant ‘evidence’ to work with and any attempt beyond the ‘known’ facts is speculative – at best.  The “I’m right” crowd are just feeding a mindless media machine with their ego driven, often inaccurate theories.  I, for one completely agree with Ben

Ben Sandilands: - "I am disappointed but ought not be surprised by the current broader discussion (way wider than it is here) where basically it has became a slanging match between the supporters of various theories, all backed up by incomplete or totally missing data as the case may be."

Choc frog for Ben – Tim Tam for Fred….

P2 – “I wait with interest for Simon's reply & for his math on the shortening of the 7th Arc radius.”

Me too mate, ....  ....me too!

Toot toot.

[Tinkicker]

Fred gets it...& comments made in relation to the B777 are 'technically' correct!

Moreover, Fred understands that the B777 shed the conventional federated avionics structure for an integrated avionics structure from it's inception. The integrated avionics architecture of the Airplane allows several functions normally housed in separate LRUs (i.e. CMU), to now be processed & implemented from within a single avionics system--the AIMS cabinet. There are two of these systems on board the B777. Each AIMS cabinet operates totally partitioned from the other. This provides system redundancy in the event that a cabinet fails.

Simon's technical knowledge, especially with regard to the B777, often appears lacking! To those who 'know' the Aircraft that comes as no surprise. But to those who don't, it's easy to fall prey to anyone over-claiming knowledge & experience, & confusing fact with opinion.

On a different note, #3 Ben says: "This matrix of events and possibilities is the main reason why I have no coherent theory as to what happened to MH370 that I’d be prepared to defend." Fair do's, Ben!

I'll throw in another choc frog & a Tim Tam.