[Peetwo]

Dolan correcting the record..

The capability of the MH370 search operation

2 June 2015

Recent news reports about the search for MH370 have included highly inaccurate assertions about the search and how it is being conducted.

The ATSB strongly refutes assertions that Fugro Survey Pty Ltd was not the best choice to undertake the underwater search or that the search methods are ineffective. The search is being carried out to the highest standards of effectiveness and quality.

“These attacks are unfounded and unfair”, said Chief Commissioner Martin Dolan. “The search for MH370 represents thousands of hours of work by hundreds of people who are dedicated, expert and professional. They are fully committed to finding the aircraft.

“The opportunity to tender services for the search for MH370 was open to the international underwater search industry. We received a number of tenders which encompassed a range of different capabilities and methods. A comprehensive and exhaustive evaluation process was conducted in line with strict Australian Government procurement and probity rules.

“I am very conscious that we must use taxpayers’ money responsibly. Fugro’s bid represented the best value for money and demonstrated that they could capably manage the technical aspects of this challenging search operation and deliver the necessary results.”

Fugro has been involved with numerous aircraft and helicopter search and recovery operations since the 1980s. They have been using the Edgetech Deeptow side-scan sonar systems since the mid-90s and have one of the largest commercial AUV fleets in the world for performing commercial surveys in deep water.

Their ability to detect man-made objects on the seafloor in ultra-deep water is evidenced by the recent detection of a previously unknown shipwreck.

“The debris in the shipwreck field was significantly smaller, and therefore harder to detect, than we expect to find with MH370,” Chief Commissioner Dolan said.
“The ATSB has put in place systems of review and expert quality assurance so we can be certain that the quality of search data meets the high standards we have specified,” said Chief Commissioner Dolan. “We selected Fugro on their capacity to meet those standards.”

As part of its quality assurance process, the ATSB has enlisted the expertise of Sherrell Ocean Services founded by Andrew Sherrell, one of the leading sonar search specialists in the world, who has worked on a number of commercial air investigations, including the search and recovery of Air France 447, TWA 800, and Egypt Air 990.

Mr Sherrell has been involved as the Quality Assurance Manager in many elements of the search for MH370, beginning with the tender process and continuing with the planning of the search and review of the gathered sonar data. Mr Sherrell said he is confident that the appropriate technology is being used.

“The equipment was tested thoroughly in ocean trials at a purpose-built test range to ensure the maximum swath width without compromising the detection capability. Fugro’s faster-than-average tow speed enables them to scan significant amounts of sea floor per operational day. As a result, we are seeing substantial coverage with the required level of resolution,” said Mr Sherrell.

“We have a rigorous and thorough quality assurance program that ensures appropriate overlap between adjacent swaths and positioning of each line as well. We are achieving very accurate and consistent results with a new state-of-the-art positioning system that gives us full confidence in the towfish position, even 9km behind the vessel.

“Furthermore, we verify this system by using the accurate bathymetry maps collected during Phase 1 of this search. By matching specific features on the seafloor, we can ensure that the positions being calculated are correct, and we do this for every single line of data collected. We also perform feature matching with the side scan sonar data between adjacent lines to ensure sufficient overlap of data is maintained. This is also done on every line as it is collected, with any deficiencies documented and catalogued.
“In addition, Fugro are using multibeam sonar to supplement the side scan sonar equipment; this covers the traditional “nadir” gap directly below the towfish. The multibeam ensures more complete coverage of the seafloor it passes over. This is optimising our rate of progress, and is a feature that is not available on some older systems that are still in use by other organisations.”

Without this type of system, a much higher percentage of seafloor would need to be covered twice to fill in this missing data. Duplicating coverage of the seafloor not only increases the cost of the search, but also the time required to cover the search area. Using a multibeam sonar in this way is a very efficient technique for covering large areas of seafloor.

“The challenges remain,” Chief Commissioner Dolan said. “The search zone is remote, the weather and sea conditions are difficult  and the search area is vast, but I’ve never had any doubt about the capabilities of Fugro, their commitment to the mission or their professionalism.”

While on the subject of 'correcting the record' it would appear that the ATSB Director of the Operational Search for MH370 Peter Foley has a further clarification for the Senate after this brief appearance at Senate Estimates:

 

The clarification... - ATSB_Foley correction 28 May  

Dear Senator Heffernan,


Subject: Budget Estimates May 2015


I write regarding some information given at Senate Estimates on May 28, some details of which were unintentionally inaccurate and could be misinterpreted.

In response to a question from Senator Rice in relation to the Integrated Marine Observing System acoustic detections around the time of the loss of MH370, I stated that there was a detection approximately an hour after the aircraft exhausted its fuel in a north-westerly direction - towards Diego Garcia and the Maldives.

This evidence may have been misleading and I wish to tender further information in relation to the analysis of acoustic detections in the search for MH370.

Low frequency hydro-acoustic signals present in the Indian Ocean were examined between March and June 2014 to determine whether they could provide any information to help define the search area. These signals were recorded by hydrophones as part of the United Nations Comprehensive Nuclear-Test-Ban-Treaty Organisation (CTBTO) or the Integrated Marine Observing System (IMOS).

Recordings of low-frequency underwater acoustic signals from data loggers and hydrophones off the WA coast (these hydrophones are located in the Perth Canyon to the west of Rottnest Island not Carnarvon as I stated) were retrieved and analysed by Curtin University's Centre for Marine Science and Technology during the search for MH370.

The ATSB requested the Curtin University Centre for Marine Science and Technology CMST) and the Defence Science and Technology Organisation to analyse these signals in an attempt to detect and localise underwater sounds that could be associated with the impact of the aircraft on the water or with the implosion of wreckage as the aircraft sank.

One acoustic event of interest was identified that occurred at a time that could have potentially linked it to MH370. This event appeared to have been received just after 0130 UTC on 8 March 2014 on one of the IMOS recorders near the Perth Canyon (RCS) and at the CTBTO hydro-acoustic station at Cape Leeuwin (HA01 ). A detailed analysis of these signals resulted in an approximate localisation for the source of the event. Based on the propagation speed of acoustic signals, the timing of the event was compatible with the time of the last satellite handshake with the aircraft, which occurred at approximately 0019 UTC, shortly before the aircraft is calculated to have entered the ocean. The location of this acoustic event was, however, incompatible with the satellite to aircraft range derived from the handshake.

Using the three hydrophones from the Cape Leeuwin station, Curtin University subsequently calculated a precise bearing that showed the signal came from the northwest, in the central Indian Ocean, with the most likely location calculated to be 5.93°S, 77.22°E with a corresponding time of the event approximately of 0039 UTC.

There is however uncertainty about where the event occurred and therefore about the time taken for the signal to arrive at the hydrophone array.

In summary, all the acoustic events recorded around the time of the likely splashdown of MH370 were carefully analysed. The one event which may have occurred close to the right time came from a direction in the Indian Ocean which was not compatible with the data derived about the aircraft's position from the satellite handshakes.

I apologise for the inaccuracy and trust that this clarifies the matter.

FCOL two brief appearances at Estimates & two 'clarifications'... 

What say you Feline Nut??- Told you so!!