Wind shear, hesitation behind plane’s bumpy landing in Istanbul: Experts

Hesitation of the pilots and the air traffic controller, rapid change in wind speed and the age-worn runway at Istanbul's Sabiha Gökçen Airport have been pointed as possible causes of the plane accident which left three dead and 180 injured on Feb. 5.

Pegasus Airlines Flight PC2193 was landing from the western province of İzmir when it skidded off the runway on Feb. 5 in inclement weather.

The preliminary assessment of the investigation commission, assigned by the Transport and Infrastructure Ministry, focused on the possibility of a "wind shear," which is defined as a sudden change in wind speed or direction over a short distance.

Normally, pilots are trained to avoid wind shear risks caused by microbursts and downbursts often by following a procedure of missed approach, according to an expert.

"The given tail wind limit for passenger planes is 10 knots. But, the limit decreases to five knots if the runway is wet. We see that the tail wind during the landing of this plane was 22 knots, and it even rose to 34 knots, or 61 kilometers per hour," said retired air traffic controller Zafer Yeşilgül.

"In such a situation the air traffic control tower should definitely not give permission for landing. Besides, the pilot can also see the wind speed on his screen. So, he should have initiated a go-around even if a landing permission was given," he added.

The decision of the two pilots, Turkish and South Korean nationals, to try for a difficult landing can be caused by a motivation to save time and fuel, aviation expert and daily Hürriyet columnist Uğur Cebeci wrote.

"Pilots always aim at landing as soon as possible to transport passengers on time. It's a hidden pressure," he wrote.

"If the ATC tower had acted more...