Hijackers may have tampered with vital cockpit equipment on the missing Malaysia Airlines jet mid-journey in a bid to avoid radar detection, aviation experts analysing a new government agency report say.
The Australian Transport Safety Bureau has released a report detailing evidence of a "not common" power outage occurring on the plane less than 90 minutes after take off from Kuala Lumpur.
Investigators revealed that after the power outage, the Boeing 777's satellite data unit (SDU) attempted to log-on to a satellite - a process called a "handshake" in aviation industry lingo.
"A log-on request in the middle of a flight is not common and can occur for only a few reasons," the investigators said. "An analysis was performed which determined that the characteristics and timing of the log-on requests were best matched as resulting from power interruption to the SDU."
The interruption of electrical power on board the Beijing-bound plane could have been the result of a hijacking attempt, said aviation expert Peter Marosszeky from the University of New South Wales.
"If there was a crew wanting to do something that was rather sinister or there were hijackers on board, they would remove power by opening up the bus-tie breakers and opening up the battery control switch. That way the aircraft virtually loses all power to just about all systems except the engines," he said.
"The engines have their own little computer and they have their own power source by a generator on the gearbox.
"You can reset the power in some way, this way the aircraft would go dead as far as any satellite contact or any information being transmitted by transponders. They can reinstate it and re-initialise the flight management computers ... it has to be a very clever pilot or person that really knows that aeroplane to be able to achieve that."
The power failure could be the result of tampering to minimise the use of the aircraft's systems, aviation safety expert David Gleave from Loughborough University told the UK's The Telegraph.
"A person could be messing around in the cockpit which would lead to a power interruption," Mr Gleave said. "It could be a deliberate act to switch off both engines for some time. By messing about within the cockpit you could switch off the power temporarily and switch it on again when you need the other systems to fly the aeroplane."
Chris McLaughlin from Inmarsat, which owns and operates a global satellite network, told The Telegraph: "It does appear there was a power failure on those two occasions ... it is another little mystery. We cannot explain it. We don't know why. We just know it did it."
ATSB investigators also reported that a second mysterious "handshake" request occured nearly six hours later. This one, they speculated, was caused by fuel exhaustion and power loss before the plane crashed into the Southern Indian Ocean.
The Malaysia Airlines plane went missing on March 8, sparking an international search for the wreckage. On Friday, the federal government announced a new search zone: a 60,000-square-kilometre area of the sea floor about 1800 kilometres west of Perth. The search begins in August.
- Sydney Morning Herald