Most civilian plane crashes are followed by speculation over whether they were caused by human error or a technical defect. With Friday’s crash at Kozhikode airport, there’s an added complication: tabletop runways.
India’s second tabletop plane crash in a decade has drawn the focus of authorities on these short runways that can challenge the best of pilots when the weather’s bad.
An Air India Express flight crashed after overshooting the runway at Kozhikode airport in Kerala on Friday night, killing 18 people and injuring scores. A very similar accident at the Mangalore tabletop airport in 2010 killed 158 people.
Landing aircraft on tabletop runways, which are located on top of a hill or a plateau with deep gorges running down their sides, is a stiff ask in poor weather conditions.
The slightest lapse in such conditions can lead to fatal crashes, three senior pilots said.
“If visibility is poor and there are tailwinds, landing on a tabletop airport becomes a challenge,” a pilot with national carrier Air India Ltd said, seeking anonymity.
The human at the centre of Friday’s crash of the Boeing 737, was Deepak Vasant Sathe, the flight captain and a former Air Force pilot described by aviation minister Hardeep Puri as one of India’s “most distinguished, experienced commanders”.
Airport infrastructure may be another factor.
“Aqua planning (drainage of water) and rubber deposits at tabletop airports are huge safety threats as these can lead to poor braking and aircraft overshooting the runway,” said another senior pilot, who, too, didn’t want to be named.
Puri said on Saturday issues like excessive rubber deposits, water stagnation, and cracks at the airport that were routinely flagged by DGCA had been addressed by airport operator Airports Authority of India (AAI) before the crash.
According to a senior official at the Directorate General of Civil Aviation (DGCA), the aviation watchdog, the crash happened because the aircraft landed at the 3,000-foot point on a runway that’s 8,500-foot long. “At the Kozhikode tabletop airport, aircraft normally land at 800 feet, but IX1344 landed beyond 3,000 feet, resulting in the accident,” the DGCA official said. “The incident is being investigated. The causes of the accident will be out soon.”
The airport at Kozhikode has two runways, both 2,700 metres in length. They have a safety feature called Runway End Safety Area (RESA) of 240 metres, as mandated by the International Civil Aviation Organization, which limit the consequences when aeroplanes overrun the end of a runway. Both are Instrument Landing System (ILS) CAT 1-enabled.
Experts are calling for India to pave runways with engineered materials arresting systems (EMAS) at seven tabletop runways—Kozhikode and Kannur (Kerala), Mangalore (Karnataka), Pakyong (Sikkim), Shimla and Kullu (Himachal Pradesh) and Lengpui (Mizoram).
EMAS, designed to stop planes from overshooting the runway, have been installed at US tabletop airports, and one senior airline official told Mint: “The accident could have been avoided if EMAS system had been put in place by airports which have runways in critical places like on top of a hill. However, myopic views of cost and high inertia prevent action being taken until forced.”
Another pilot, who analysed Friday’s wreckage pictures, said photographs of the engine show the thrust lever position was ‘full-forward’.
News Source: Livemint