Satellite Images Are Called ‘Credible Lead’ in Plane Search
By KEITH BRADSHER and NICOLA CLARK
Malaysia’s defense minister on Wednesday said images taken Sunday showed
122 objects, some up to 75 feet in length, floating southwest of
Australia and that “this is still the most credible lead that we have.”
Asia Pacific
New Satellite Images Said to Be ‘Credible Lead’ in Jet Search
KUALA
LUMPUR, Malaysia — Malaysia’s defense minister announced on Wednesday
evening that Airbus Defense and Space, Europe’s main commercial
satellite company, had forwarded images taken on Sunday of 122 objects
floating southwest of Australia and said that his country had asked
Australia to check if they were debris from Malaysia Airlines Flight
370.
While
the objects might turn out to be unrelated to the missing aircraft,
Defense Minister Hishammuddin Hussein said, “this is still the most
credible lead that we have.”
The
objects are up to 75 feet, or 23 meters, in length, and are visible
through gaps in clouds over an area of 154 square miles, or 400 square
kilometers, he said. Some of the objects are bright, he noted without
elaboration. Metal objects that had recently entered the ocean might be
reflective.
Malaysia
forwarded the information to Australia on Wednesday afternoon, and it
was unclear if the floating objects can be checked before dark or if an
inspection may need to wait until Thursday, Mr. Hishammuddin said.
Video|1:11
Credit Azhar Rahim/European Pressphoto Agency
Malaysia Says New Objects Found in Ocean
Hishamuddin Hussein, Malaysia’s defense
minister, said that new satellite images were “the most credible lead”
in the search for the missing Malaysia Airlines Flight 370.
The
Australian Maritime Safety Authority said in a statement that it had
resumed search operations after a one-day halt for bad weather on
Tuesday and that at least four aircraft were scheduled to be searching
on Wednesday night.
The
floating objects are 1,589 miles, or 2,557 kilometers, southwest of
Perth. If the debris turns out to be from the missing plane, the next
step would be to figure out how far it might have drifted from where the
aircraft might have splashed down, to begin an undersea search, Mr.
Hishammuddin said.
Extreme Challenges for Investigators
Conditions in the Indian Ocean — where officials believe
Flight 370 may have ended — are some of the harshest in the world. Full Graphic »
India
India
Africa
Africa
INDIAN OCEAN
INDIAN OCEAN
Australia
Australia
Search
areas
Search
areas
Antarctica
Antarctica
Wind speed
Low
High
High
Wave height
Low
High
High
The
United States Navy has sent an undersea listening device and a sonar
device. But each needs to be towed far underwater behind a ship
traveling scarcely faster than a person walking on land.
The
listening device could pick up signals from the plane’s data recorders
before they stop transmitting pings in two to three weeks but needs to
be towed within a mile of them for reliable detection. The sonar will
work even after the data recorders go silent but needs to be even closer
to detect wreckage on the seabed.
Finding
floating debris from the plane might help provide closure for the
families and friends of the passengers and crew, but may prove of
limited use in locating the data recorders, oceanographers cautioned.
The debris could have drifted hundreds of miles in the 18 days since the
plane disappeared, said Jianping Gan, an oceanographer at the Hong Kong
University of Science and Technology who has done research aboard a
Chinese icebreaker in the waters around Antarctica.
Jason Ali, an earth sciences professor at Hong Kong University
who has studied currents in the Indian Ocean, said that “even if you’ve
got floating material, if it has been floating for two and a half
weeks, it’s not going to have much relation to the wreckage” on the
seabed.
Mike
Purcell, a senior engineer at the Woods Hole Oceanographic Institution
in Massachusetts, who led two underwater search expeditions for the
wreck of Air France Flight 447 in the Atlantic in 2010 and 2011, said
that the current search zone for Flight 370 was far more remote than the
location of the Air France wreckage and that the seas and weather
conditions were known to be considerably rougher.
“That
can slow down your progress considerably, because it makes it more
difficult to operate, to get the vehicles in and out of the water,” he
said. And bad weather can mean days of waiting to resume the search.
Tracking Flight 370
The sequence of events known by the authorities, in local times.
Mr.
Purcell estimated that there were fewer than a dozen underwater search
vehicles in the world equipped with the sonar and imaging technology
required for a deepwater search of this scale. These are operated by a
handful of private companies and oceanographic institutes as well as by
the United States Navy, he said.
Mr.
Purcell said one advantage was that the sea floor in the southern
Indian Ocean was relatively flat compared with the highly varied terrain
of the mid-Atlantic. The depth of the water is comparable, however, at
more than 10,000 feet.
Where Objects Have Been Found
In the search for Malaysia Airlines Flight 370.
5,000 FT.
Possible flight paths
AUSTRALIA
INDIAN OCEAN
WATER DEPTH
10,000 FT.
Perth
10,000 FT.
Areas previously
searched
Albany
15,000 FT.
10,000 FT.
OBJECTS SPOTTED
March 16 (satellite image)
Monday’s
planned
search areas
March 18 (satellite image)
March 24 (by a Chinese plane)
Military
submarines have sophisticated equipment for listening for ships or
other submarines. But unlike towed sonar like the Bluefin-21, which the
United States Navy is sending and which can descend to 14,700 feet, or a
towed pinger detector, which can plunge 20,000 feet, military
submarines are designed to operate within a few hundred feet of the
surface. That limits their ability to detect pings from far below the
surface in water of different densities, moving at different speeds and
at different temperatures.
For
now, aircraft from Australia and other countries have been looking in
an area the size of the western and southwestern United States, where
the plane is believed to have disappeared after its last signals to a
satellite. They have not extended the search to all the places where
debris might have drifted. But because the area of the aircraft’s
disappearance is so far from land, roughly a four-hour flight in each
direction, planes can spend only a couple of hours searching.
Making
matters worse, oceanographers said, is that currents in the southern
Indian Ocean are less well understood than in more heavily trafficked
seas. A violent storm on Tuesday, one of many in the region as the
southern hemisphere’s winter approaches and days become shorter, has
further churned the waters.
And
any debris sticking up out of the water will have been pushed by the
wind in directions that may be different from prevailing currents. “With
any wind, it’ll act like a sail,” Mr. Ali said. Waves may also have
pushed objects in unpredictable directions, making it hard to calculate
the movements of any debriss.
Even
finding the data recorders, although extremely difficult, may not be
enough to explain what happened to Flight 370. The cockpit voice
recorder stores only the two most recent hours of sounds in the cockpit
before the aircraft ceases operating. Investigators have been most
interested in why the plane turned around over the Gulf of Thailand
roughly seven hours before it is believed to have run out of fuel over
the southern Indian Ocean.
The
separate data recorder for various aircraft instruments and controls
would have saved information from the plane’s sharp turn, but might not
reveal the intent of whoever was in the cockpit or if the turn was
deliberate, as the Malaysian authorities have suggested.
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