Australian search team leader, Air Chief Marshal Angus Houston, has announced that after 6 consecutive days of no further signal detections they are calling off the use of the Towed Ping Locator.  

In addition Angus Houston says: “the chance of finding any floating debris has diminished”; and visual debris searches are due to be discontinued in the next 48 hours pending further consultation with all parties assisting in visual search…..

The search team has determined to go underwater. They are moving to deploy the autonomous underwater side scan radar known as Bluefin-21.
Each deployment of the Bluefin-21 will take 24 hours. Two hours to reach depth (approx. 4,500 meters); 16 hours “on station” as it sweeps the sea floor [5k x 8k];  two more hours to resurface, and four hours to download and prepare for redeployment.
The use of the Bluefin-21 side-scan radar begins today.
In addition an oil slick was located yesterday approximately 5,500 meters downrange of the search area where the previous 4 ping signals were determined. Two liters of samples were taken, however it will take several days for analysis to determine chemical composure of oil slick residue.
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