09 April 2014 (21:23 UTC-07 Tango 08 April 2014)/08 Jumada t-Tania 1435/20 Farvardin 1393/10 Wu-Chen 4712
Australian Defence ship Ocean Shield has heard pings on two more occasions, for a total of four times since 05 April. The Chinese ship Haixun 01 picked up signals twice.
The signal is 33.331 kilohertz, at 1.106 second intervals, consistent with flight data recorders.
Search will now concentration on an area 75-thousand square kilometers (46,602 square miles) in size. The ocean bottom in that area is known to be silty. Silty sea bed actually absorbs sonar and other acoustic sound detection systems. The silt could also be interfering with the data recorders’ pingers.
Satellite tracking data indicates MH370/CZ748 suffered engine flame out (due to running out of fuel) approaching the area of the pings.
The number of ships involved will be kept to a minimum because their props will generate noise that will interfere with the detection of pings. Aircraft will be dropping sonobuoys.
No wreckage has been seen.
During the search for Air France flight 447, it took underwater vehicles 20 days after the pings were heard before the plane was found.