Last sighting

In one of the most baffling mysteries in modern aviation, no trace of the plane nor any sign of wreckage has been found despite a search by the navies and military aircraft of more than a dozen countries.

The last sighting of the aircraft on civilian radar screens came shortly before 1:30 a.m. Malaysian time last Saturday (1730 GMT Friday), less than an hour after it took off from Kuala Lumpur, as the plane flew northeast across the mouth of the Gulf of Thailand. That put the plane on Malaysia's east coast.

Malaysia's air force chief said on Wednesday an aircraft that could have been the missing plane was plotted on military radar at 2:15 a.m., 200 miles northwest of Penang Island off Malaysia's west coast.

This position marks the limit of Malaysia's military radar in that part of the country, a fourth source familiar with the investigation told Reuters.

When asked about the range of military radar at a news conference on Thursday, Malaysian Transport Minister Hishammuddin Hussein said it was "a sensitive issue" that he was not going to reveal.

"Even if it doesn't extend beyond that, we can get the cooperation of the neighboring countries," he said.

The fact that the aircraft - if it was MH370 - had lost contact with air traffic control and was invisible to civilian radar suggested someone aboard had turned its communication systems off, the first two sources said.

They also gave new details on the direction in which the unidentified aircraft was heading - following aviation corridors identified on maps used by pilots as N571 and P628. These routes are taken by commercial planes flying from Southeast Asia to the Middle East or Europe and can be found in public documents issued by regional aviation authorities.

In a far more detailed description of the military radar plotting than has been publicly revealed, the first two sources said the last confirmed position of MH370 was at 35,000 feet about 90 miles off the east coast of Malaysia, heading towards Vietnam, near a navigational waypoint called "Igari". The time was 1:21 a.m.

The military track suggests it then turned sharply westwards, heading towards a waypoint called "Vampi", northeast of Indonesia's Aceh province and a navigational point used for planes following route N571 to the Middle East.

From there, the plot indicates the plane flew towards a waypoint called "Gival", south of the Thai island of Phuket, and was last plotted heading northwest towards another waypoint called "Igrex", on route P628 that would take it over the Andaman Islands and which carriers use to fly towards Europe.

The time was then 2:15 a.m. That's the same time given by the air force chief on Wednesday, who gave no information on that plane's possible direction.

The sources said Malaysia was requesting raw radar data from neighbors Thailand, Indonesia and India, which has a naval base in the Andaman Islands.

Malaysia says last sighting of plane possibly off West Coast	Live Report:Malaysia extended search to the Straits of Malacca

	Video: How can an airplane disappear? MH370 is not the first aircraft that has disappeared without a trace.
	Video: Officials remain puzzled Tension mounted as the search for the missing Malaysian airplane continued.