Fear, anxiety, desolation, and grief ... Airline pilot community is awash in a tide of emotions in the wake of disappearance of a Malaysian passenger aircraft over South China Sea four days ago.

There is no trace of wreckage, much less meaningful radar track, of the B777-200 that mysteriously disappeared with 239 people on board.

Weather threat Animated discussions on the subject end ‘with a big exclamation mark’, a senior commander with Air India told Business Line .

Open Pacific Ocean, of which South China Sea is a part, is a vast cauldron of big weather events in the upper levels and offers a challenge for pilots.

But the Air India commander ruled them out as a cause for the disappearance of the aircraft for more reasons than one.

No weather station on ground, of which there were many around under the footprint of the flight path, had indicated any such threat.

Even if there was one, other passing aircraft would have reported it to ground control in Malaysia, Vietnam, Singapore, Indonesia, Hong Kong or Guam.

The annual cyclone season too has ended, and no thunderstorm build-up was warned of around the time of disappearance of the aircraft.

Safest phase Also, the aircraft was cruising at a height of 35,000 feet, a phase considered safest and event-free during a flight. At this height, there is hardly any violent weather that can possibly lead to a disintegration of the aircraft as argued by some people.

Akhilesh Gupta, expert meteorologist and operational forecaster, says that it is in the lower altitudes that aircraft have to contend with violent weather. He referred to dangerous ‘squall lines’ and huge thunderstorms with electrical discharge that could hit the fuselage with catastrophic results.

But he was not too sure if the delayed winter in the northern hemisphere that saw extreme weather at many places had set off matching events up above.

The commander speaking to Business Line ruled out any parallel with an Air France A330 aircraft that plunged into the Atlantic with 228 people on board in 2009. In that case, it had flown straight into a huge thunderstorm, stalled and lost height rapidly.

Curious aspect In contrast, area of the incident in which the Malaysian airliner went untraceable is under constant gaze of radars on all sides.

And that is the curious aspect about it all. The huge aircraft cannot vanish just like that unless the pilot switched off transponders on board under duress.

This opens up the probability that the aircraft may have been hijacked before being guided to a different destination. Else, the wreckage would have to show up somewhere in the ocean, given that four days have elapsed since its disappearance.

The other plot that sits well with the scenario is the intentional switch-off of systems on board as part of suicide bid. In this case, all tracking radars would get in such a scenario is a blip from the metal body of the aircraft. No communication can be had with the pilot.