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As mystery over missing MH370 deepens, more theories surface

Published on Mar 18, 2014 3:33 PM

From mid-air stalking to cyber-hijacking, more theories have surfaced as the mystery over the missing Malaysia Airlines plane deepens, and efforts to track down the plane make little headway. We round up some of the popular but unverified theories:

1. Mid-air “stalking”
Some aviation enthusiasts and unnamed pilots have raised the possibility that the Malaysia Airlines plane could have shadowed another plane to escape detection by ground radar.

The Malaysian Insider, which quoted an unnamed pilot, reported on Tuesday that whoever was in control of the missing Boeing 777-200ER would just have to switch off all the plane’s lights and follow the night to avoid visual contact. “Once the transponders are off and the lights are dimmed, flight MH370 becomes a ghost flight in the night sky. It can follow other planes closely or fly below them without anyone knowing,” said the pilot. “It will know where the other planes are from the radio chatter.”

MH370, with its transponder switched off, would be invisible to the aircraft being “stalked” because the latter’s Traffic Collision Avoidance System raises alert based on transponder data.
This possibility was also reported on The Aviationist website, which quoted Mr Ed Pernotto, a retired US Air Force Reserve Colonel who has flown with armed forces of Malaysia and Thailand.

“When you fly over water or from point to point, pilots are frequently directed to change frequencies, told to turn, climb, descend, you name it. This is all ‘in the clear’ and not privileged communications, anyone with the right radio on the right frequency would hear it,” said Mr Pernotto. Whoever was in command of MH370 “could simply have slipped in behind a northbound airliner and flown slightly higher and behind by a mile or two matching the speed and not exceeding the airliner in front of them”, he added.

To a ground radar controller, the planes would appear as one or two “blips” depending on how close they were. “When they get close to the field, the slip-off unnoticed in the middle of China, pull the throttles back, and make a very quiet approach and landing at their destination,” he said.

But those who came up with this theory acknowledged that it would be difficult for MH370 to trail another aircraft at night, without radar help.

2. Fly “nap of the earth”
MH370 could have dropped to an altitude of 5,000 ft, or possibly lower, to avoid commercial radar coverage after it turned back from its Kuala Lumpur-Beijing route on March 8, reported Malaysia’s New Straits Times, quoting officials involved in the probe.

Slate magazine also suggested that one possibility might be to fly “nap of the earth”, close enough to the surface of the earth to elude the sweeps of a radar beam. “Nap” stands for “near as possible”. This could explain why the aircraft was able to penetrate the military radar coverage of multiple nations, according to Slate, which suggested that the aircraft has most likely ended up in western China or an adjacent Turkic area.

But flying at such low altitude would require a much higher fuel burn and result in a lower speed, some noted.

3. Terrain masking
Whoever was piloting the plane could have also used a technique known as “terrain masking” to avoid detection, officials investigating the mysterious disappearance of MH370 told Malaysia’s New Straits Times.

Officials told the newspaper that “it's possible that the aircraft had hugged the terrain in some areas that are mountainous to avoid radar detection”. This technique, called terrain masking, is used by military pilots to fly to their targets stealthily, using the topography to mask their approach from prying microwaves.

Professor Jason Middleton, head of the aviation department at New South Wales University, told British newspaper Guardian that avoiding radar was a well-known technique. “Radar goes in a straight line. If you are in the shadow of a mountain or even the curve of the Earth – if you are under the radar beam – you can’t be seen,” he said. “The further (radar beams) go out the weaker they are and the further they need to come back. Radars have dead zones which are low and also which are far away.”

But flying a large aircraft this way is dangerous because it puts tremendous stress on the airframe, said other experts. Airsickness could also easily set in.

4. Cyber-hijacking
British anti-terrorist expert Sally Leivesley put forth a bold theory - that the plane could have fallen victim to the world’s first ‘‘cyber-hijack’’.

The former Home Office scientific adviser said a plane could be taken over using a mobile phone or USB stick. Hackers could change the plane’s speed, altitude and direction by sending radio signals to its flight management system, she told the Sunday Express in London. It could then be landed or made to crash by remote control. It was possible, said Dr Leivesley, for hackers to get into the main computer network of the plane through the inflight, onboard entertainment system. The hacking threat was raised at a science conference in China last year, she added.

But other experts said there was no way one could hijack a plane with a mobile phone.

MH370 graphic