KUALA LUMPUR - The international team investigating the disappearance of Flight MH370 scrutinised seven areas to identify the likely causes during its year-long probe.
It started out by looking at the airworthiness and maintenance schedule of the Boeing 777-200, which had passed every annual Certificate of Airworthiness test mandated by the Department of Civil Aviation (DCA) since it was issued in 2002.
According to the interim statement, the plane with the serial number 28420 underwent its last test on May 15, 2013, and a torn left flaperon inboard seal was found to be the only problem.
The aircraft had also undergone several major repairs for its wing tips during minor accidents in 2012.
Next, the team looked at Air Traffic Control (ATC) transcripts from 1.19am on March 7 to 6.32am on March 8.
The statement noted that a total of five hours and 13 minutes passed between the last communication from MH370 with the ground and the first message triggering the "Distress Phase".
The transcripts showed conversations between the ATC centres in Kuala Lumpur and Ho Chi Minh after MH370 vanished from radar as it passed Malaysian air space into Vietnam.
It said the confusion started when the MAS Operations Centre said MH370 was still exchanging signals with the Flight Explorer tracking system and that it was "somewhere over Cambodia". Three hours later, MAS admitted that the information from the flight tracker was based on projections and was not reliable.
The investigators also scrutinised cargo onboard the flight, with close attention to the lithium ion (Li-ion) batteries and the shipment of mangosteens, which made up the bulk of the cargo on the plane.
The statement said the 221kg of batteries did not go through security checks but they were not regulated as "dangerous goods" because the packing adhered to International Civil Aviation Organisation (ICAO) guidelines.
The statement also included military radar data that tracked the diversion of the aircraft near waypoint IGARI over the South China Sea and that it was last tracked at waypoint MEKAR, between Sumatra and Penang, at about 2.22am.
Finally, the report looked at the seven "handshakes" made by the plane's satellite communications (Satcom) system and Ground Earth Station (GES), which led investigators to search in the southern Indian Ocean.
It said two out of the seven handshakes were initiated by MH370 but did not include the plane's flight ID.
The report also included the organisational and management information of the DCA and Malaysia Airlines.
THE AREAS OF SCRUTINY
Airworthiness & Maintenance and Aircraft Systems
ATC operations from 1719 to 2232 UTC on March 7, 2014 (1.19am to 6.32am Malaysian time on March 8, 2014)
Diversion from Filed Flight Plan Route
Organisational and Management Information of DCA and MAS