US official says pattern of transmissions sent from jet after it dropped off radar implied human intervention or 'act of piracy'
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Almost a week after Malaysia Airlines flight MH370 vanished, it has emerged that the aircraft could have flown on for a further five hours with its communications systems deliberately switched off.
With no trace of the plane or wreckage despite a huge international search, one US official told Associated Press that the pattern of transmissions sent from the jet after it dropped off the radar implied human intervention or "an act of piracy". The focus of the search operation shifted to the Indian Ocean on Friday.
Two communication systems appear to have stopped transmitting at different times after the plane left Kuala Lumpur for Beijing, but further electronic signals were picked up by satellites after the last contact, which could be analysed to help estimate the location of the aircraft.
The signals, described as a series of hourly pings to the satellite, indicated that the plane's communication system was still working, but not transmitting data. The information would support theories that the plane's system was deliberately switched off.
The signals, provided to the investigators by British satellite telecommunications company Inmarsat, do not transmit location but can indicate a position and distance relative to the satellite, which could give a guide to a rough direction of travel over several hours. David Coiley, vice president, aviation, at Inmarsat, said any total absence of communication during normal aviation would be "a highly unusual situation".
The Wall Street Journal quoted US officials who said these signals persisted for another five hours.
The White House refused to comment on suggestions that US officials believe there may have been "an act of piracy".
"This is a difficult and unusual situation and we are working hard in close collaboration with the Malaysian government to investigate a number of possible scenarios for what happened to the flight," said spokesman Jay Carney.
"Unfortunately, definitive conclusions still cannot be drawn at this time," he added. "I don't have conclusive answers. I don't think anyone has."
Military radar evidence suggests that the Boeing 777 may have been deliberately flown west towards the Andaman Islands after it last made contact with air traffic control in the early hours of Saturday 8 March. Sources told Reuters that the flight path of an unidentified aircraft, believed by investigators to have been the MH370 jet, followed a route with specific navigational waypoints, suggesting someone with aviation training was at the controls.
The systems are designed to allow people to communicate when they want to communicate, constantly.
"When the system is not transmitting or receiving data on the aircraft, it will send network signalling info to establish that the aircraft satellite communication is switched on to say that the system could communicate.
The last known position of MH370 was at 1.21am at 35,000ft roughly 90 miles off the east coast of Malaysia, as the plane, with 239 people on board, made its way towards Vietnam, en route to Beijing.
If the aircraft picked up on the military radar is the missing jet, the data suggests it veered dramatically and deliberately westwards, heading north-east of Indonesia's Aceh province towards a navigational waypoint used for carriers headed towards the Middle East. From there, plot indications suggest the plane zigzagged towards the Thai island of Phuket and then towards the Andaman Islands and possibly onward towards Europe.
Malaysian military officials have previously confirmed that an aircraft that could have been MH370 was last seen on military radar at 2.15am some 200 miles off Malaysia's west coast.
A senior Malaysian police official told Reuters: "What we can say is we are looking at sabotage, with hijack still on the cards."
According to two US officials who spoke to ABC News, the Boeing 777's data reporting system was shut down at 1.07am, while the transponder – which sends back information to civilian radar regarding performance, location and altitude – was turned off at 1.21am.
The US has since moved surveillance planes into an area of the Indian Ocean 1,000 miles west of the Malayasian peninsula after an undisclosed suggestion that the plane may have crashed there. "We have an indication the plane went down in the Indian Ocean," a senior Pentagon official said.
The USS Kidd destroyer, which has helicopters aboard, will be moved to the western tip of the Malacca Strait, where it meets the Andaman Sea.
Most of the leads on the potential location have come from unattributed US sources assisting the Malaysian investigation. Under international protocols, the country where the missing aircraft was registered must lead the investigation.
Malaysian police have spent the past week investigating whether any personal or psychological problems affecting the crew or passengers may have had a role in the jet's disappearance, in addition to mechanical failure, hijacking or sabotage. Friday's revelations that the plane may have flown towards the Andaman Islands are the first real indication of a sinister cause.
At a press conference on Friday, Malaysia's defence and acting transport minister, Hishammuddin Hussein, said authorities were investigating the possibility that the plane's communications systems had been deliberately shut down and said there were four or five possibilities as to why they may have been turned off.
"It could have been done intentionally, it could be done under duress, it could have been done because of an explosion," he said. "That's why I don't want to go into the realm of speculation. We are looking at all the possibilities."
Hishammuddin confirmed that the plane's passengers and crew were being looked into and added: "If investigation requires searching the pilots' homes, it will be done."
Aviation experts from the UK – in addition to a team from Rolls-Royce, which manufactured the 777's engines – were due to arrive in Malaysia on Friday night to help with the investigation, said the civil aviation chief, Azharuddin Abdul Rahman.
A total of 57 ships, 48 aircraft and 13 nations are taking part in the search and rescue mission, which has been expanded further east into the South China Sea and further out into the Indian Ocean. Indian planes and ships have begun searching the 572 islands comprising the Andaman and Nicobar island groups using heat-seeking devices to help find the missing plane, and would likely extend the search to the Bay of Bengal.
A Chinese government spokesman would not be drawn on whether China believed the plane had flown for several hours or whether it had asked the US about the reports.
He added that China had asked Chinese commercial vessels to take note of any floating objects which might be connected to the missing flight. A subsequent comment suggested this applied to vessels in the Strait of Malacca.
The Chinese state news agency Xinhua reported on Friday evening that search vessel Haixun 31, which had been at work in the Gulf of Thailand, was heading to the Strait of Malacca to continue work there. Reported by guardian.co.uk 6 hours ago.
• Follow the latest updates here
Almost a week after Malaysia Airlines flight MH370 vanished, it has emerged that the aircraft could have flown on for a further five hours with its communications systems deliberately switched off.
With no trace of the plane or wreckage despite a huge international search, one US official told Associated Press that the pattern of transmissions sent from the jet after it dropped off the radar implied human intervention or "an act of piracy". The focus of the search operation shifted to the Indian Ocean on Friday.
Two communication systems appear to have stopped transmitting at different times after the plane left Kuala Lumpur for Beijing, but further electronic signals were picked up by satellites after the last contact, which could be analysed to help estimate the location of the aircraft.
The signals, described as a series of hourly pings to the satellite, indicated that the plane's communication system was still working, but not transmitting data. The information would support theories that the plane's system was deliberately switched off.
The signals, provided to the investigators by British satellite telecommunications company Inmarsat, do not transmit location but can indicate a position and distance relative to the satellite, which could give a guide to a rough direction of travel over several hours. David Coiley, vice president, aviation, at Inmarsat, said any total absence of communication during normal aviation would be "a highly unusual situation".
The Wall Street Journal quoted US officials who said these signals persisted for another five hours.
The White House refused to comment on suggestions that US officials believe there may have been "an act of piracy".
"This is a difficult and unusual situation and we are working hard in close collaboration with the Malaysian government to investigate a number of possible scenarios for what happened to the flight," said spokesman Jay Carney.
"Unfortunately, definitive conclusions still cannot be drawn at this time," he added. "I don't have conclusive answers. I don't think anyone has."
Military radar evidence suggests that the Boeing 777 may have been deliberately flown west towards the Andaman Islands after it last made contact with air traffic control in the early hours of Saturday 8 March. Sources told Reuters that the flight path of an unidentified aircraft, believed by investigators to have been the MH370 jet, followed a route with specific navigational waypoints, suggesting someone with aviation training was at the controls.
The systems are designed to allow people to communicate when they want to communicate, constantly.
"When the system is not transmitting or receiving data on the aircraft, it will send network signalling info to establish that the aircraft satellite communication is switched on to say that the system could communicate.
The last known position of MH370 was at 1.21am at 35,000ft roughly 90 miles off the east coast of Malaysia, as the plane, with 239 people on board, made its way towards Vietnam, en route to Beijing.
If the aircraft picked up on the military radar is the missing jet, the data suggests it veered dramatically and deliberately westwards, heading north-east of Indonesia's Aceh province towards a navigational waypoint used for carriers headed towards the Middle East. From there, plot indications suggest the plane zigzagged towards the Thai island of Phuket and then towards the Andaman Islands and possibly onward towards Europe.
Malaysian military officials have previously confirmed that an aircraft that could have been MH370 was last seen on military radar at 2.15am some 200 miles off Malaysia's west coast.
A senior Malaysian police official told Reuters: "What we can say is we are looking at sabotage, with hijack still on the cards."
According to two US officials who spoke to ABC News, the Boeing 777's data reporting system was shut down at 1.07am, while the transponder – which sends back information to civilian radar regarding performance, location and altitude – was turned off at 1.21am.
The US has since moved surveillance planes into an area of the Indian Ocean 1,000 miles west of the Malayasian peninsula after an undisclosed suggestion that the plane may have crashed there. "We have an indication the plane went down in the Indian Ocean," a senior Pentagon official said.
The USS Kidd destroyer, which has helicopters aboard, will be moved to the western tip of the Malacca Strait, where it meets the Andaman Sea.
Most of the leads on the potential location have come from unattributed US sources assisting the Malaysian investigation. Under international protocols, the country where the missing aircraft was registered must lead the investigation.
Malaysian police have spent the past week investigating whether any personal or psychological problems affecting the crew or passengers may have had a role in the jet's disappearance, in addition to mechanical failure, hijacking or sabotage. Friday's revelations that the plane may have flown towards the Andaman Islands are the first real indication of a sinister cause.
At a press conference on Friday, Malaysia's defence and acting transport minister, Hishammuddin Hussein, said authorities were investigating the possibility that the plane's communications systems had been deliberately shut down and said there were four or five possibilities as to why they may have been turned off.
"It could have been done intentionally, it could be done under duress, it could have been done because of an explosion," he said. "That's why I don't want to go into the realm of speculation. We are looking at all the possibilities."
Hishammuddin confirmed that the plane's passengers and crew were being looked into and added: "If investigation requires searching the pilots' homes, it will be done."
Aviation experts from the UK – in addition to a team from Rolls-Royce, which manufactured the 777's engines – were due to arrive in Malaysia on Friday night to help with the investigation, said the civil aviation chief, Azharuddin Abdul Rahman.
A total of 57 ships, 48 aircraft and 13 nations are taking part in the search and rescue mission, which has been expanded further east into the South China Sea and further out into the Indian Ocean. Indian planes and ships have begun searching the 572 islands comprising the Andaman and Nicobar island groups using heat-seeking devices to help find the missing plane, and would likely extend the search to the Bay of Bengal.
A Chinese government spokesman would not be drawn on whether China believed the plane had flown for several hours or whether it had asked the US about the reports.
He added that China had asked Chinese commercial vessels to take note of any floating objects which might be connected to the missing flight. A subsequent comment suggested this applied to vessels in the Strait of Malacca.
The Chinese state news agency Xinhua reported on Friday evening that search vessel Haixun 31, which had been at work in the Gulf of Thailand, was heading to the Strait of Malacca to continue work there. Reported by guardian.co.uk 6 hours ago.