Robotic Bluefin 31 submarine drone and MH370

Australian Joint Agency Coordination Centre (JACC) has used up to 12 international aircrafts and 14 vessels to search for the missing aircraft MH370 in southern Indian Ocean. Vessels such as Haixun and Ocean Shield had detected acoustic pulses or pings believed to be from the black box recorders of the ill-fated aircraft.  Now, it has proceeded to robotic Bluefin 21 submarine drone to scour the 4500 metre deep seabed covered with several metres of sea mud. It is daunting. We need good luck.