THIRUVANANTHAPURAM: A day after the Air India Express plane skidded off the Kozhikode Airport runway and split into two claiming 18 lives, the focus on Saturday was on finding the reasons for the crash. While a section of aviation experts and staff at the airport pointed fingers at the cockpit crew, others questioned the standard of the runway. While an investigation has begun, an analysis of the flight data recorder (black box) and cockpit voice recorder (CVR), which were recovered on Saturday, is expected to provide vitals clues. They were sent to New Delhi for retrieving data.
Civil Aviation Minister Hardeep Singh Puri, talking to reporters in Kozhikode, said: “Let’s not speculate on the reasons. The AAIB (Aircraft Accident Investigation Bureau, under the Civil Aviation Ministry) is conducting an investigation,” he said. The minister, however, ruled out tabletop runway being the reason for the accident.
“This is not the only airport with a tabletop runway. We’ve other airports and our neighbouring countries too have airports with tabletop runways,” he said.
Theories and rumours about the possible reasons for the crash — from hydroplaning to tailwind to pilot error — were doing the rounds right from Friday night.
Doha-based aviation expert Jacob K Philip said the chances of hydroplaning are very remote as there were only light showers during the time of the accident.
“At least 3mm water is required on the runway for hydroplaning, a process in which a layer of water builds between the wheels of the aircraft and the runway surface, leading to a loss of traction that prevents the aircraft from responding to control inputs. But the topography of the airport and its runway and the light rain during the time of accident can rule out this,” he said.
Another theory is that tailwind (wind that blows in the direction of travel of the aircraft) caused the plane to skid off. The data accessed by TNIE revealed that there was only 12.7 knots of tailwind at the time.
“The narrow-bodied aircraft can operate in tailwind up to 15 knots. So, that possibility can also be ruled out,” Jacob said.
An Airport Authority of India staff, who witnessed the accident, said the pilot attempted to land on runway 28 first. But it didn’t come through due to bad weather and the aircraft circled the airport a couple of times.
When it again approached runway 10, just opposite of runway 28, the visibility was around 2000 metres, and the pilot was given permission for landing.But things took a turn for the worse as the plane touched down almost past mid-way of the 2,860-metre runway, while the threshold marking for touchdown is about 300 metres from the start.
“The pilots either did not have the time to pull up when they realised it or they thought that the aircraft could be stopped before reaching the Runway End Safety Area (RESA),” said an airport staff.
“It overshot the runway and went through the RESA, skidded off and plunged 35 feet down.”
While experts said only decoding of data from the black-box can reveal what went wrong, they pointed out that in the 2010 Mangaluru air crash, the pilots of Air India Express flight IX-812 misjudged the length of the runway while landing and then tried to get the plane airborne again after landing beyond the touchdown zone.
The social media was abuzz with reports that the pilot had drained fuel before making a belly landing due to bad weather.
Experts said before making a belly landing, the ATC has to be alerted to make preparations.
No such communication passed between the cockpit crew and the ATC in this case, said airport staff. Kapil Kaul, CEO and director of CAPA Advisory, an aviation consulting firm, said he does not want to speculate on the cause of the accident but added that the runway should be extended.
Proper runway surface condition should be maintained, especially at airports with tabletop runways, he said.
“We need to evolve a system to ensure pilots have information from ATC about the runway surface condition during monsoons when we have torrential rains,” Kaul said.
An airport employee told TNIE: “Though there was a slight mist in the area, we could see the aircraft landing safely and go past the fire station. But we didn’t see it coming back to the apron and heard a noise. When we rushed to the spot, we saw passengers coming out of the broken fuselage.”
Another airport staffer said, “Fire force rushed to the spot and sprayed foam to form a protective carpet around the aircraft to avoid the plane catching fire. The left engine of the aircraft was almost dislodged from its position and fuel supply was cut. Luckily, we could prevent the aircraft from catching fire.”