Investigators involved in the search and rescue operations for the missing Malaysia Airlines flight MH370 are reportedly looking at the flight profile of the aircraft to see if it used "terrain masking" after it went missing from radar coverage.

According to Malaysian paper The New Straits Times, trained pilots can fly safely in low altitudes and "be able to perform 'terrain masking'."

NST said: '"Terrain masking" is a means of avoiding active radar by positioning the aircraft so that there is natural earth hiding it from the radio waves sent by the radar system. This technique is used by military pilots to fly to their target stealthily, using the topography to mask their approach from prying radar microwaves."

The report said flight MH370 might have dropped to an altitude of 5,000 ft or 1.5km to avoid detection after air traffic control lost contact with the plane on March 8.

Meanwhile, Malaysia Airlines chief executive Ahmad Jauhari Yahya said he was unaware of any reports saying the plane might have flown lower than 5,000 ft.

"We are not aware of any such reports. We will have to check with the investigators," he said in an NST report today.