[Peetwo]

Joe the sneak on MH370 debris - Finally a true tin-kicker verifies debris and not a Muppet in sight - yea hah! Oh and Griffin on why the ATSB is definitely in the right area...   (Joe in blue & Griffin in red):

Credit: AFP

This handout image taken by the Lotter family on March 9, 2016 and released on March 12, 2016 shows a debris found by the family off the coast of Mozambique in December 2015, that could be a part of the missing Malaysian flight MH370. Picture: Candace Lotter/ Handout/ AFP

By: Terry van der Walt

Durban key to MH370 mystery?
news/south-africa/kwazulu-natal / 
27 March 2016 at 12:16pm
By: Terry van der Walt

A top investigator looking into the disappearance of Malaysian flight MH370 has examined plane debris found by a KZN teenager and believes it “almost certainly” comes from the doomed plane that claimed the lives of all 239 people on board.

And it is highly likely that more pieces of debris, furnishings and personal items of passengers will drift ashore on our coast, further intensifying the call for beachgoers to be on the lookout.

Last week relatives of those on board the flight from Kuala Lumpur to Beijing launched a global appeal, Voice370, urging South Africans, fishing vessels and ships to help look for traces of the plane, in what has become the world’s largest aviation investigation.

On Saturday Joe Hattley, of the Australian Transport Safety Bureau, tasked with heading the international probe into MH370, told the Sunday Tribune that the piece recovered by Wartburg teenager Liam Lotter, as well as the piece found by Blaine Gibson, both on the Mozambican coast, had been examined by him in Australia last week.


He made a call for people to take a photograph in situ, exactly how they find any flotsam, and to then place it in a plastic bag and notify the South African Civil Aviation Authority (SACAA).


“The ‘flaperon’ piece found on the island of Reunion on July 29 last year is still with French authorities in Toulouse, and it has been confirmed to have come from the flight. I believe negotiations are under way between the Malaysian authorities and the SACAA to recover the latest piece found on Monday near Mosselbay by Neels Kruger,” said Hattley.

SACAA spokesman Kabelo Ledwaba confirmed this piece had been collected, and would be handed over to Malaysian authorities.


Hattley said that even with these four pieces, it was still impossible to refine the seabed search area, since so many factors could affect the movement of debris.


“It is still very difficult to work out where the plane went down. The drifting patterns of each piece are rather erratic, so the more data we get, including more debris finds, the more we will be able to narrow the search area, which is 120 000km,” he said.


He said Dr David Griffin, an oceanographic expert with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) of Australia, had provided useful insights to the crash investigators, using data provided by the Global Drifter Programme (GDP).

The GDP uses data from buoys regularly placed in the ocean over the past 30 years, which record surface temperatures and ocean currents.

This data tends to back up the seabed search area favoured by the Australian Transport Safety Bureau: a vast area of the Indian Ocean, along an arc the plane may have flown before it ran out of fuel. Investigators believe the plane deviated from its flight path, and turned southward near the island of Sumatra.

Griffin believes the flaperon piece found on Reunion was likely to have followed a similar path to that of drifters.


“This data shows that the flaperon probably entered water warmer than 18°C within a month or two of the crash, so barnacle nauplii may have started settling and growing on the flaperon for most of the voyage.


In his report (www.marine.csiro.au/~griffin/MH370/) he concludes: “The flaperon finding does, however, support the flight path analysis conclusion that the 39°S-32°S segment of the seventh arc is indeed the highest priority search region for MH370.”

Hattley said readers who had questions on anything they might find on our shores were welcome to e-mail him on atsbinfo@atsb.gov.au
Sunday Tribune

 
&..from DG:

MH370 - drift analysis

David Griffin





28 February 2016 update: 'No step' item found on a sandbank off Mozambique

An item which appears to be a wing fragment, with NO STEP printed on it, has been found by Blaine Gibson on a sandbank in the Mozambique Channel. The item has been handed in to authorities for investigation. If it can be identified as being from MH370, this brings to two the number of items potentially usable for oceanographic back-tracking.



Unlike the flaperon found on La Reunion, however, this item is not heavily encrusted with sea life, so it has probably spent a significant length of time either weathering in the sun and/or washing back and forth in the sand at this or some other location. The time at sea is therefore possibly much less than the 716 days that have elapsed since 14 March 2014, and the path taken may have been two or more distinct segments.


The tracks of Global Drifter Program drifters arriving in the Mozambique Channel (during 1985-2015) were overwhelmingly from the east, as shown at right. Two were close to the ATSB search area 700d prior to being in the Mozambique Channel, suggesting that the 'no step' item could very well have followed a similar path. But other drifters arrived near Mozambique from very different points along the 7th arc, showing that those, too, could also be regarded as possible origins of the item.


As with the flaperon, therefore, we conclude that while the location of this finding does not cast doubt on the ATSB's choice of search area (based on the Inmarsat handshakes), it can not provide particularly strong support for it either, because the trajectories of drifting items are so chaotic.


Trajectories of Global Drifter Program drifters

2 October 2015 update: Composite trajectories



Introduction


Few drifters complete journeys long enough to be directly relevant to the task at hand, especially since we are only interested in the subset of the drifters' trajectories that are before or after specific places, and with or without the drogue attached. We have therefore elected to create composite trajectories by adding shorter trajectories together head-to-tail. There are gaps in time and space involved, but we think that the benefits of the vastly greater number of composite trajectories more than compensates for the damage done by these gaps.


Method


Our method is simple: at the end of a partial trajectory, we do a search for all trajectories that meet distance-away, time-of-year and drogue on/off criteria. At the ends of all those trajectories, another set of searches is done. Drifter data density is quite uneven, potentially biasing the results, so we under- or over-sample the available trajectories appropriately (by time-shifting in the latter case). We have limited the number of partial trajectories to three or four for the results shown here, so they are either 538/3 or 538/4 days long. This results in a large number of trajectories. Using the trajectories back from La Reunion, we can estimate the possible location of the flaperon 508 days earlier (the time between 8 March 2014 and 29 July 2015) by mapping the density of points 508days (+/- 30days, center-weighted) back along all the trajectories.


One way to rationalise this approach is to consider that the best way to estimate where a drifter might go, having come to a certain point, is to look at the paths of other drifters that have passed near that point. This is, after all, what we were doing by looking at single-drifter trajectories, anyway. So now, as well as single-drifter trajectories, we have very many more three- or four-drifter trajectories. We have done this for a selection of La Reunion-backward and drogued and un-drogued trajectories

• .
  
  
  
  
  Results
  
  The image above shows our estimate of the likelihood function of where the flaperon was on 8 March 2014. The 7th arc is added for reference, with the 'high priority' search zone shown in bold. The sea-floor search zone is clearly within the zone of likely origins. The southern end of the search zone is close to the southern flank of the likelihood function, while the northern end of the search zone is towards the eastern flank, but at slightly higher likelihood than the southern half. But why is there a broad maximum NW of the arc, e.g. near 35S, 75E - 30S, 90E? Because this is where drifting buoys are evidently concentrated, moving at lower average velocity and therefore spending more time. We have verified that this is not an artefact of where drifters are deployed or lose their drogues. There is a (leaky) mechanism that concentrates them here in the centre of the gyre. Our back-tracking inevitably concludes that the most likely prior location of the flaperon was where it probably spent a lot of time, regardless of exactly where it entered the water nearby. This assumes that the flaperon drifted exactly like an undrogued drifter, which is probably not the case, being a very different shape. But it probably drifted much more like an undrogued drifter than a drogued one (in which case we would conclude that it entered the water much farther north).
  
  
  The end points of forward-tracks originating near the northern half of the high-priority seafloor search zone are distributed fairly evenly around La Reunion. A similar result is obtained for the southern half, reinforcing our earlier conclusion that if the plane had crashed where it is thought to have, that Reunion would be one of the most likely places where debris would be found.

MTF...P2