KUALA LUMPUR: AN analysis of satellite and aircraft performance data has indicated that Malaysia Airlines flight MH370 had more fuel than was initially estimated.
As such, the aircraft could have traveled further south than the area in the southern Indian Ocean which was initially thought to have been the place where it crashed after running out of fuel.
It is understood that a failed second phone call by MAS to the satellite phone aboard the aircraft was also used to refine the search area and the plane’s possible flight paths.
Through analysis of the satellite and aircraft performance data, independent specialists are considering some 1,000 possible flight paths to gain a consensus as to where the aircraft entered the water.
The Joint Agency Coordination Centre (JACC), which is leading the search for MH370, said these flight paths indicate a high probability search area close to a long but narrow arc of the ocean west of Perth.
“The latest information and analysis confirms that MH370 will be found in close proximity to the seventh arc, which is 4,000km long. The expert satellite working group continues to work very closely with the Australian Transport Safety Bureau (ATSB) to determine where the aircraft most likely entered the water,” it told the New Straits Times via email.
The focus will be on a 60,000-square-kilometre area in the southern Indian Ocean, 1,800km off the coast of Western Australia.
With the 1,000 flight paths and additional fuel factors to consider, aviation expert Associate Professor Captain Dr Mohd Harridon Mohamed Suffian said the new information was strongly indicative, as even a small alteration in the flight path changes the search area significantly.
He said a small deviation from the flight path would put the aircraft thousands of kilometres away from the original search area.
“The new information of the plane turning south much earlier entails that the airplane did not use the majority of its fuel moving westward, suggesting much of its fuel was used to go further south than the current search area.
“Hence it is perhaps possible that the airplane's location would be further south of the seventh arc or the Broken Ridge (Kerguelen Plateau),” said Harridon, adding that he was convinced the plane would be found in the areas.
Although the Aircraft Communications Addressing and Reporting System (ACARS) on MH370 was disabled at 1.21am, the system cannot be totally disabled from the aircraft, as it goes in standby mode.
The last known location of MH370 identified by military radar was west of Malaysia, after which aircraft ‘handshakes’ were recorded by Inmarsat ground station at Perth.
MH370 was flying for another 7 hours 38 minutes after ACARS was switched off and it had been estimated that it had about eight hours of fuel in its tanks. The normal flight from Kuala Lumpur to Beijing takes about six hours.
The last (seventh) handshake or partial handshake was initiated by the plane at 8.19am on March 8, which was responded by the ground station and the aircraft replied with a 'log-on acknowledgement’.
This is said to be in response to an interruption in the plane’s power supply, whereby the Boeing 777’s “ram air turbine” kicked in.
At 9.15am on March 8 the aircraft failed to respond to its hourly handshake attempt, suggesting that the plane had exhausted its fuel, consistent with the maximum endurance of the aircraft.
When asked to explain the Boeing 777 satellite communication and Acars systems, Harridon said the log on request was usually done automatically by the computer of the airplane if it detects any anomalies in the aircraft system.
He said the anomalies include electrical power surges or lack of power, engine performance below par or other.
“It's quite difficult to actuate the log on request manually but theoretically it could be done by simulating anomalies during flight. The Auxiliary Power Unit (APU) starts up during flight (in order to replace the airplane main power), the computer onboard the airplane would detect this start up and theoretically an automatic log on request would be sent since this start up is considered an anomaly.
“The APU and small wind turbine would pop out underneath the belly of the airplane if the primary source is not available.
“Usually Boeing 777 electrical system would reboot immediately after the loss of an engine or both engines. This is to ensure a smooth transition of using other means of electrical source,” he said.
Harridon said by looking at the available satellite data the rebooting was actuated immediately on MH370.
On what could have caused the power interruption, Harridon said that it could have occurred if one or either engines failed or if thunderstorms caused a voltage surge.
On the question of the plane flying on autopilot until it ran out of fuel as reported by ATSB chief commissioner Martin Dolan, he said the plane would have flown on a straight path.
“To go to a certain coordinate or waypoint using autopilot, the pilot needs to key in the coordinate or waypoint using the scratch pad of the aircraft before engaging the autopilot. Unless the autopilot was programmed to follow specific waypoints, then the airplane would fly towards the waypoints and this perhaps would be in a zigzag manner if those waypoints are not within a straight path,” he said.
Australian authorities have said that the straight path was based on the electronic handshakes the plane had exchanged with satellites.
MH370 was carrying 227 passengers and 12 crew members. It went off radar on March 8 just one hour after taking off from KL International Airport at 12.41am.
The flight was scheduled to land at Beijing International Airport at 6.30am on the same day.