For all the
headline-grabbing stories about security breaches, intoxicated pilots and faulty
equipment, sometimes a commercial plane’s worst enemy is Mother Nature.
appears to be the case for a new Boeing 737, operated by Indonesian budget
carrier Lion Air, that crashed into the shallow waters off the coast of Bali on
13 April, just short of the runway at Ngurah
Rai Airport. At the helm was an experienced pilot who managed to save all 108
passengers and crew, but told Reuters it felt like his aircraft was “dragged”
down by wind as he fought to regain control. The crash – and the pilot’s
alarming comments – are renewing fears about the chilling phenomenon known as windshear.
is a sudden change in wind speed and direction that can cause planes to rapidly
lose altitude. They are often caused by storms creating strong downdrafts of
rely on wind speed and direction to control takeoff and landing, typically doing
so in the direction of the wind. But sudden shifts in wind speed and direction can
cause planes to lose control, especially during takeoff and landing, when they
are low to the ground and have reduced engine power and little room to manoeuvre.
is it that Lion Air’s crash was caused by a windshear? Officials from a bevy of
agencies – including Indonesian state officials, the US National Transportation Safety Board, the Federal Aviation Administration (FAA), the Meteorological and Geophysics
Agency and Boeing – are
investigating the incident and expect to release their findings within a month.
But initial tests show that the pilot was experienced, was not under the
influence of drugs or alcohol, and the plane, a brand new Boeing 737, had no
technical issues, all of which rules out pilot or plane error.
more, weather reports indicate a strong storm and driving rains were developing
as the plane attempted to land, which lends support to the idea of windshear as
But the surprising – and unnerving – point is that aviation officials
consider windshear to be a problem that was solved long ago. Between 1964 and
1985 windshear was responsible for some 26 civil aircraft crashes in the US,
leaving about 500 fatalities and about 200 injuries, according to
NASA. The most famous incident involved a Delta Airlines
Lockheed Tristar, which crashed in 1985, killing 134 passengers and crew near
the Dallas-Fort Worth airport.
Since then, windshear-related incidents have dropped considerably,
thanks to FAA- and NASA-developed technology that warns pilots of oncoming storms.
The Predictive Windshear
System, available below 700m, warns pilots some 10 to 40 seconds ahead of
windshear to go around the bursts.
But for now, a
lot of unknowns remain, including whether the Lion Air crash was caused by windshear, whether the
windshear warning system was functioning on the aircraft and perhaps the
biggest question for the airline industry – whether windshear may again become
a serious concern.