Crew
members on board a U.S. Navy P-8A Poseidon man their workstations while
assisting in search operations for Malaysia Airlines flight MH370 over
the Indian Ocean, in this handout photo taken March 16, 2014. Malaysia
has appealed for help and international coordination in a search for its
missing passenger jet that stretches across two corridors from the
Caspian Sea to the southern Indian Ocean, diplomats said on Sunday.
Malaysia must "immediately" expand and clarify the scope of the search for a Malaysia Airlines jetliner that disappeared with 239 people on board, the Chinese Foreign Ministry said on Monday in a statement posted on its website.
Meanwhile, Foreign Ministry spokesman Hong Lei said at a regular briefing in Beijing that China's ambassador to Malaysia met Malaysia's foreign minister on Monday.
Engineer suspect
Malaysian police are investigating a flight engineer who was among the passengers on the missing Malaysia Airlines plane as they focus on the pilots and anyone else on board who had technical flying knowledge, a senior police official said.
The aviation engineer is Mohd Khairul Amri Selamat, 29, a Malaysian who has said on social media he had worked for a private jet charter company.
Cont.....reading
Historic satellite search
Finding a missing Malaysia Airlines plane may hinge on whether searchers can narrow down where they need to look using satellite data that is inexact and has never been used for that purpose before, search and rescue experts say.
Authorities now believe someone on board the Boeing 777 shut down part of the aircraft's messaging system about the same time the plane with 239 people on board disappeared from civilian radar.
But an Inmarsat satellite was able to automatically connect with a portion of the messaging system that remained in operation, similar to a phone call that just rings because no one is on the other end to pick it up and provide information.
No location information was exchanged, but the satellite continued to identify the plane once an hour for four to five hours after it disappeared from radar screens.
Based on the hourly connections with the plane, described by a US official as a "handshake," the satellite knows at what angle to tilt its antenna to be ready to receive a message from the plane should one be sent.
Using that antenna angle, along with radar data, investigators have been able to draw two vast arcs, or "corridors" — a northern one from northern Thailand through to the border of the Central Asian countries Kazakhstan and Turkmenistan, and a southern one from Indonesia to the southern Indian Ocean.
The plane is believed to be somewhere along those arcs.
Air crash investigators have never used this kind of satellite data before to try to find a missing plane, but after pursing other leads it's the best clue left.
"The people that are doing this are thinking outside the box. They're using something that wasn't designed to be used this way, and it seems to be working," said William Waldock, who teaches accident investigation at the Embry-Riddle Aeronautical University in Arizona.
"In terms of search and rescue, they're probably going to have rewrite the book after this."
25 countries, 43 ships, 58 aircraft
Authorities generally believe the plane crashed into the ocean, although they can't rule out the possibility that it may be on land somewhere.
Twenty-five countries are involved in the search for the plane, using at least 43 ships and 58 aircraft.
"If it really is out there in the Indian Ocean, they're going to need a lot more than that," Waldock said.
"It's immense. It takes a lot of effort, a lot of people, a lot of ships and airplanes."
In order to narrow down the location low-flying planes are searching broad swathes of water for any sign of debris.
The search is complicated by the vast amount of trash floating in the world's oceans.
If the airliner did crash into the ocean, some lighter-weight items such as insulation, seat cushions, and life jackets, as well as bodies not strapped to seats, are likely to be floating on the surface, Waldock said.
The heavier parts of the plane would sink, with depths in some parts of the Indian Ocean at over 15,000 feet(4,570 meters), he said.
When suspected debris of a plane is found, the nearest ship — whether it's a search ship or a commercial vessel that happens to be in the area — is sent to the site.
A small boat or life raft usually has to be lowered into the water for a closer look at the debris to judge whether it might have come from the missing plane.
If searchers find airplane debris, ocean currents will have already moved away from where the plane went into the water.
Searchers will then have to use their knowledge of currents in the region to estimate how far and from what direction the debris came, and work backward to that location.
The airliner is equipped with two "black boxes" — a flight data recorder that contains hundreds of types of information on how the plane was functioning, and cockpit voice recorder that contains pilots' conversations and noise in the cockpit. Both are equipped with underwater locator beacons, sometimes called "pingers," that emit a sonic signal that can only be heard underwater. Sonar on ships can sometimes pick up the pings, but they are best heard using a special pinger locator device that is lowered into the water.
The US Navy in the Indian Ocean region has a pinger locator. "It's boxed up, it's ready to be sent somewhere," said a US official. "Right now, there just isn't enough evidence to tell us where to send it."
The official agreed to speak only on condition anonymity because he wasn't authorised to speak publicly.
Global call
Malaysia has appealed for help and international coordination in a search for its missing passenger jet that stretches across two corridors from the Caspian Sea to the southern Indian Ocean, diplomats said on Sunday.
Malaysian officials briefed envoys from 22 countries on the progress of the investigation after calling off a search in the South China Sea for the jet that vanished from radar screens more than a week ago, with 239 people on board.
Although countries have been coordinating individually, the broad formal request at a meeting of ambassadors marked a new diplomatic phase in a search operation thought increasingly likely to rely on the sharing of sensitive material such as military radar data.
"The meeting was for us to know exactly what is happening and what sort of help they need. It is more for them to tell us, 'please put in all your resources'," T.S. Tirumurti, India's high commissioner to Malaysia, told Reuters.
The diplomatic initiative could become significant as nation ponder whether to share any military data on the Boeing 777's fate, and fills a void left by the failure of Southeast Asian nations to work as a bloc on the crisis, a diplomat said.
"There are clearly limits to military data," the diplomat said, adding that nations were nonetheless aware of the strong public interest in cooperation on a civilian issue.
Malaysian Defence Minister and Acting Transport Minister Hishammuddin Hussein said Malaysia had itself fed the findings of its own military radar tracks into what is now a domestic criminal enquiry into suspected hijacking or sabotage.
He declined to say whether Kuala Lumpur had asked others to open up their military radar tracks, but told a news conference that it had asked for both primary and secondary radar data.
Experts say military forces mainly use primary or classic radar, which works by listening for its own echo bouncing back off a potentially unfriendly object.
Civil air traffic control mostly uses secondary radar, which relies on hearing a signal sent back from the aircraft's transponder along with data designed to identify the plane.
It was the apparently deliberate decision to turn the jet's transponder off that left Malaysian authorities relying on the blips picked up by primary military radar to form the theory that the aircraft - on a flight to Beijing - had turned back west before disappearing.
Underscoring the caution surrounding the request for deeper co-operation, at least one country represented at Sunday's ambassadorial meeting asked Malaysia to supply its request in writing, a diplomat present at the talks said.
Southeast Asia has been at the centre of a regional arms race for several years amid tensions in the South China Sea, with maritime surveillance and air defences high on the list of hardware laid out at last month's Singapore Airshow.
The search for the missing jet is focusing on a wide stripe of territory either side of two arcs formed by satellite plots of the aircraft's last known possible position.
The northernmost of these stretches runs north through Thailand and China and bends towards India, Pakistan and then Central Asia, over some of the world's most strongly guarded defences.
If the jet did stray into those areas, sensitivities over whether and how such sensitive data could be shared could be further complicated by potential embarrassment over how such a large unidentified aircraft could have continued unchallenged.
Defense analysts said on Saturday that the jet's disappearance raised awkward questions about the strength of regional or even global air defences.
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