The Air India Express crash at Kozhikode airport on August 7 could have been averted had the country’s civil aviation regulator, Directorate General of Civil Aviation, followed its own regulations after a similar accident involving another Air India Express flight at Mangalore airport in May 2010. “It was an accident waiting to happen,” underscored aviation safety experts.
DGCA had stated on Friday that it was raining heavily when pilots of the ill-fated Air India Express Boeing 737 plane from Dubai tried to land. The flight was supposed to land on Runway 28, but due to low visibility, the flight landed on the opposite Runway 10, which is said to have had tailwinds due to heavy rains. The tailwind is likely to have increased the speed of the flight and it skidded till the end of the runway, before falling into the valley below and breaking into two.
Both Mangalore and Kozhikode are table-top airports. A table-top runway sits on a hill, usually with sides dropping to a deep valley. In 2010 after the Air India Express crash in Mangalore that killed 158 people on board, an enquiry report by a former Indian Air Force Air Marshal BN Gokhale had warned about overshooting the paved runway surface.
A tabletop airport has limited space at the end and beginning of the runway and in case of Kozhikode, there is a 70-feet drop after the runway. The crash on Friday was also because the Air India Express flight overshot the runway.
“Tabletop airports per se are not dangerous. Where and how it goes wrong depends on how you use it and how the regulator monitors it. I have written multiple times to DGCA about Kozhikode airport and there is a case pending at the Kerala High Court about the airport since 2016,” pointed out Yeshwant Shenoy, a lawyer and aviation safety activist.
After the 2010 Mangalore crash, DGCA declared 11 airports as critical airports and Kozhikode was one of them. Apart from Kozhikode, airports in Leh, Kullu, Shimla, Port Blair, Agartala, Lengpui, Mangalore, Jammu, Patna and Latur were on the list.
“In aviation, everything is terminology. No airport in the world is termed critical; only the DGCA uses the term. DGCA is a regulator, not a media house to declare names for airports. It is supposed to regulate,” underscored Shenoy.
What they need to do, Shenoy said, is to bring in operational restrictions. This means that the airport should operate only in certain weather conditions, during a certain time period and only certain aircrafts can fly in. “Now, that is technical work, and no one wants to work. So, conveniently they termed the airport critical and left it at that,” explained Shenoy.
Kozhikode airport has several problems, but instead of addressing them, the DGCA gives it temporary declarations to keep the airport running though all the issues are permanent.
“The Calicut airport is not safe for widebody aircrafts such as Boeing 777 or Airbus 330 or Boeing 747, so they changed the classification of the airport to permit widebody aircraft. This is illegal and completely wrong. It was pointed out and in 2015, DGCA stopped operation of wide-body aircraft to Kozhikode,” explained Mohan Ranganathan, a civil aviation safety expert. However, since 2019, widebody aircrafts are permitted at Kozhikode airport. In the intervening period, nothing was done to change the systems on the ground.
The flight that landed in Kozhikode was a Boeing 737. “Theoretically, it is safe, but not in tailwind wet conditions. There are no obstacles on the West, so the pilot attempted to land on Runway 10, but due to tailwinds, it overshot the runway. We are lucky that the wing did not break. If the wing had broken, the fuel would have spilt on the engine and it could have caught on fire even in the rain,” explained Ranganathan. The pilots aborted landing twice as the weather conditions were severe and the runway did not have enough light.
Another issue pointed out by aviation experts is the runway in Calicut airport. A runway with brute surfaces is required. Whenever a flight lands on a runway, it leaves a lot of rubber. Unlike car tyres, plane tyres are smooth, so the grip has to come from the surface rather than the tyre. The rubber is supposed to be removed on a regular basis, but the Airport Authority of India did not do its job and the DGCA did not act on it.
“The runway has a lot of rubber deposit; it’s not a flat runway as is being projected. It is almost like an inverted V. It’s got a steep upslope and a steep downslope. So, from either ends it’s not a flat runway. If an aircraft is landing from the West and touches down a little late, it will touch the runway after the hump. That’s what happened to this aircraft,” explained Ranganathan.
“There’s a steep downslope, a rubber-covered runway and in the rain the friction is very low. It does not have the 155-metre safety area. Beyond the runway it is a 70-metre drop onto the ground. To make it safe, according to guidelines, there must be a 60-metre runway strip and 240-metre runway end safety area (RESA) on either ends of the runway. Calicut airport does not have it,” highlighted Ranganathan
DGCA has been ignoring a number of warnings. The runway has only 75 metres on either side, when it should have 155 metres on either side of the centre line. “So, when there such narrow strip, which is also a safety strip, they are supposed to have restrictions on crosswinds. They have been issuing licences to Calicut airport without enforcing these norms. We had pointed this out in 2010 but the DGCA never bothered about it. All the audits which they have done are a joke,” remarked Ranganathan. He was one of the members of the advisory committee set up by the Ministry of Civil Aviation after the 2010 crash.
It was a contaminated runway on Friday due to heavy rains in the state. This means that there was more than 3 mm deep water on the runway, yet the authorities didn’t shut the airport.
There should be a proper obstacle assessment around the Calicut airport. “As they cannot extend the airport, the authorities must put an Engineered Material Arresting System (EMAS), even though its expensive,” said Ranganathan. Also known as an arrester bed, the EMAS is a bed of engineering material, which would help in halting an aircraft that has overrun.
If an EMAS system was there, it could have saved a few lives. “These are not solutions, but mitigation efforts. All that DGCA really needs to do it follow its own rules,” added Shenoy
According to reports, at both Mangalore and Kozhikode, the Airports Authority of India and the DGCA reportedly declined the proposal to have an EMAS.
“This is the first of series of air accidents that will happen in India. There is not a single airport in the country which is safe. DGCA has violated its own laws. Everyone would think that the Delhi airport is safe, but DGCA has filed an affidavit in Delhi High Court stating that there are 369 obstacles around the airport. These are obstacles which come in the flight path,” warned Shenoy.