KUALA LUMPUR, Malaysia- Officials revealed a new timeline Monday suggesting the final voice transmission from the cockpit of the missing Malaysian plane may have occurred before any of its communications systems were disabled, adding more uncertainty about who aboard might have been to blame.
The search for Flight 370, which vanished early March 8 while flying from Kuala Lumpur to Beijing with 239 people on board, has now been expanded deep into the northern and southern hemispheres. Australian vessels scoured the southern Indian Ocean and China offered 21 of its satellites to help Malaysia in the unprecedented hunt.
With no wreckage found in one of the most puzzling aviation mysteries of all time, passengers' relatives have been left in an agonizing limbo.
AP Photo/Malaysia’s acting Transport Minister Hishamuddin Hussein shows maps of northern search corridor during a press conference at a hotel near the Kuala Lumpur International Airport, in Sepang, Malaysia Monday.
Investigators say the Boeing 777 was deliberately diverted during its overnight flight and flew off-course for hours. They haven't ruled out hijacking, sabotage, or pilot suicide, and are checking the backgrounds of the 227 passengers and 12 crew members - as well as the ground crew - for personal problems, psychological issues or links to terrorists.
Malaysian Defense Minister Hishammuddin Hussein said finding the plane was still the main focus, and he did not rule out that it might be discovered intact.
"The fact that there was no distress signal, no ransom notes, no parties claiming responsibility, there is always hope," Hishammuddin said at a news conference.
Malaysian Airlines CEO Ahmad Jauhari Yahya said an initial investigation indicated that the last words ground controllers heard from the plane - "All right, good night" - were spoken by the co-pilot, Fariq Abdul Hamid. A voice other than that of Fariq or the pilot, Zaharie Ahmad Shah, it would have been clearest indication yet of something amiss in the cockpit before the flight went off-course.
Malaysian officials said earlier that those words came after one of the jetliner's data communications systems - the Aircraft Communications Addressing and Reporting System - had been switched off, suggesting the voice from the cockpit may have been trying to deceive ground controllers.
However, Ahmad said that while the last data transmission from ACARS - which gives plane performance and maintenance information - came before that, it was still unclear at what point the system was switched off, making any implications of the timing murkier.
The new information opened the possibility that both ACARS and the plane's transponders, which make the plane visible to civilian air traffic controllers, were turned off at about the same time. It also suggests that the message delivered from the cockpit could have preceded any of the severed communications.
Turning off a transponder is easy and, in rare instances, there may be good reason to do so in flight - for example, if it were reporting incorrect data.
The Malaysian plane does not appear to fit that scenario, said John Gadzinski, a 737 captain.
"There is a raised eyebrow, like Spock on Star Trek - you just sit there and go, 'Why would anybody do that?'" Gadzinski said of what he is hearing among pilots.
Other pilots in the United States cautioned against reading too much into what little is known so far about the actions of the Malaysia Airlines crew.
"You can't take anything off the table until everything is on the table, and we don't even have an aircraft," said Boeing 737 pilot Mike Karn, president of the Coalition of Airline Pilots Associations.
Authorities have pointed to the shutdown of the transponders and the ACARS as evidence that someone with a detailed knowledge of the plane was involved. But Bob Coffman, an airline captain and former 777 pilot, said that kind of information is not hard to find in the digital age.
Authorities confiscated a flight simulator from the pilot's home Saturday and also visited the home of the co-pilot in what Malaysian police chief Khalid Abu Bakar initially said were the first police visits to those homes.
But the government, which has come under criticism abroad for missteps and foot-dragging in releasing information, issued a statement Monday contradicting that account, saying police first visited the pilots' homes as early as March 9, the day after the flight disappeared.
Coffman said the flight simulator could signify nothing more than the pilot's zeal for his job.
"There are people for whom flying is all consuming," he said, noting some pilots like to spend their off-duty hours on simulators at home, commenting on pilot blogs or playing fighter-pilot video games.
Although Malaysian authorities requested that all nations with citizens aboard the flight conduct background checks on them, it wasn't clear how thoroughly the checks were done in Malaysia.