REVEALED: Missing Malaysian Plane #MH370 changed course before co-pilot's last message

The abrupt U-turn made by the missing Malaysia Airlines passenger plane is believed to have been programmed into the on board computer before the last radio contact was made with the co-pilot.

The change in direction in the Kuala Lumpur to Beijing flight on March 9 was made about 12 minutes before Fariq Abdul Hamid told controllers: 'All right, good night', sources have claimed.

The timing of the change in Flight 370's plan is the latest twist in the mystery of the missing aircraft, which was carrying 239 people.

Although it appears that the change in direction had been planned and executed in the cockpit before contact was lost with the plane, the information does not suggest a sinister motive.

'Some pilots program an alternate flight plan in the event of an emergency. We don't know if this was an alternate plan to go back to Kuala Lumpur or if this was to take the plane from some place other than Beijing,' Greg Feith, a former investigator for the National Transportation Safety Board told NBC News.

The flight path change was first confirmed by authorities on Saturday, who said the aircraft had veered off course because of 'deliberate action by someone on the plane'.

To change a flight path, someone with knowledge of aircraft would have had to enter navigation codes into the Flight Management System in the cockpit.

The system guides the plane along the route chosen, in normal circumstances, by the pilots, and information from the computer is sent back to the airline's maintenance crew.

However, the information was not relayed to the crew and it remains unclear whether it was closed down before or after the last verbal contact with the pilots, Malaysia Airlines CEO Ahmad Jauhari Yahya said.

Former FAA spokesman Scott Brenner told Fox News however: 'One of the pilots clearly had the intention ... that he was going to take [the plane] in a different direction.

'It's 100 percent clear this pilot, or this co-pilot, was going to take this plane with the intent of doing something bad.'

He added: 'For a pilot or co-pilot to punch in a new waypoint in their flight management system without the other one noticing would be hard to do.'

Ross Aimer, a retired United Airlines pilot, said it would have taken 'extensive training' to turn the plane round and reprogram the flight system.

More than a week after the flight disappeared, a leading aviation expert has suggested that Asian military officials may be staging a mass cover-up because they do not want to expose holes within their countries' air defences.

The Malaysian Airlines jet went missing at 1.30am on Sunday, March 9. But it wasn't until the following Tuesday that the Malaysian Air Force reported they had spotted the aircraft on radar over the Strait of Malacca at 2.15am.

Thailand's military later claimed that they detected a plane at 1.28am, eight minutes after MH370's communications went down, heading towards the Strait.

They said they didn't share the information right away because they were not asked for it.