An underwater search has begun for the black box belonging to
missing Malaysia Airlines flight MH370 - a slow process that
authorities concede is akin to a shot in the dark.
Australian navy vessel Ocean Shield and the British
oceanographic survey vessel HMS Echo yesterday deployed
"pinger detectors" and began slowly converging on each other
over a 240km tract of the Indian Ocean.
All of the data that has been used to determine where the
Boeing 777 probably ran out of fuel - including the final
ping picked up by satellite, the likely speed of the plane
and the fuel burn rate - has now been fully analysed.
Search teams are slowly combing the area using underwater
technology, hoping at the same time that debris from the
plane will be seen on the surface, which would allow them to
"backtrack" to the crash site.
"I think we've got to the end of the process of analysis,"
retired Australian Defence Force chief, air chief marshal
Angus Houston, who has been recruited to lead the Perth-based
search coordination unit, said on Friday.
"The data we've got is the data we've got.
"Hopefully, the calculations are putting us in the right
Asked whether the search for the black box was a shot in the
dark, US Navy Captain Mark Matthews said it was an apt
Ocean Shield and HMS Echo were listening for a 37.5 kilohertz
signal that repeats every second and has a detection range of
Capt Matthews said the process was slow, at about 2-3 knots,
meaning it would take a couple of days to cover 240km.
"We're searching on what information we do have, our best
guess at where it would have been lost," he said.
"There's a lot of smart people that did the analysis that
determined the plane was likely on this course. It's the best
information we have. But certainly, it's a broad search.
"If you tow directly over it, you're going to be hearing it
for about an hour before if fades out of range, you're then
going to circle around it and then come back through it, so
you're going to get good positional information."
Air chief marshal Houston said other sophisticated underwater
search devices on the Ocean Shield included a vehicle that
could search the ocean floor unmanned and in deep water for
"And we've got a couple of other devices that can assist with
the search that can be dropped from the air," he said.
While the battery on the black box beacon was expected to run
out of power within days, crews could still search underwater
once it had stopped transmitting, he said.
The plane and satellite-based search for debris was still
important as it would narrow the search area, he said.
"Instead of searching over an area the size of Ireland, we
might be able to get into an area which is the size of
metropolitan Perth, for example.
"When you come to the use of the underwater devices, that's
going to help immensely."
The 217,000 square kilometre search area, about 1700
kilometres northwest of Perth, would be adjusted as required,
The flight disappeared on March 8 while flying from Kuala
Lumpur to Beijing.
All 239 passengers are presumed dead.