india

Updated: Aug 27, 2019 09:36 IST

Four of the five runway excursions reported this year happened within 72 hours in late June and early July, according to information the Directorate General of Civil Aviation (DGCA) has provided under the Right to Information (RTI) act filed by this correspondent.

An Air India Express flight veered off the taxiway after landing on June 30 and got stuck in soft ground at the Mangalore airport. A SpiceJet flight from Bhopal to Surat overshot the runway after landing the same day. Runway excursions happen when an aircraft veers off the runway while taking off or landing.

On July 1, another SpiceJet flight from Jaipur overshot the runway after landing due to heavy rains in Mumbai. Air traffic was affected for the next four days as the aircraft remained stuck on the runway.

A day later, a SpiceJet flight from Coimbatore overshot the runway in Mumbai. Another SpiceJet flight from Delhi had an unstabilised final approach and overshot the runway at Shirdi on April 29.

Also Read: 2 SpiceJet pilots who overshot Mumbai runway banned from flying for a year

They have been rare in recent years with an exception in 2017 when five such cases were reported. As per DGCA, one case each of runway excursion was reported in 2014 and 2018 while two in 2015 and three in 2016.

Experts blame unstabilised approaches, late touchdowns and wet runways for such excursions, which can cause deaths, injuries and also damage to the aircraft.

Aviation safety expert Mohan Ranganathan said the increasing number of runway excursions also shows a lack of training and understanding of pilots regarding correct landing procedures.

“This also means checking standards are poor as the flight safety department should be able to identify potential overruns by monitoring digital flight data recorders,” Ranganathan said.

He said the trend of unstabilised approaches or late touchdown can be understood from that and the regulator can identify pilots, who have such tendencies. Ranganathan said airport conditions like wet runways contribute to such cases after touchdowns. He added if a touchdown is late, it constitutes pilot error.

DGCA chief Arun Kumar said they have taken measures like directives on operations during monsoon and runway friction tests to avoid runway excursions. He added no such incident has been reported since the series of incidents in June and July.

The DGCA issued an air safety circular in the first week of July asking airlines and airport operators to take extra precautions to avoid such cases during the monsoon season.

Unprecedented growth in air traffic could be another reason for the growing number of such incidents, according to the DGCA official.

The number of aircraft in India was 620 as on July 31, 2018, up from 448 in March 2016, according to DGCA’s annual report. The number of annual flights grew to 26.05 lakh in 2018-19, against 23.24 lakh in 2017-18 and 20.49 lakh in 2016-17, according to the annual traffic report of the civil aviation ministry.

As many as 4.60 lakh flights took off and landed at the Delhi airport alone in 2018-19, up from 4.41 lakh in 2017-18 and 3.97 lakh in 2016-17. In Mumbai, there were 3.21 lakh flight movements in 2018-19, against 3.20 lakh in 2017-18 and 3.05 lakh in 2016-17.

A DGCA circular on August 6 asked airports handling over 210 aircraft per runway daily to do friction tests once weekly. Those handling 151 to 210 aircraft will have to do the friction tests once in two weeks, it said. During an audit last year, DGCA found that at some airports, the runway friction values were found below the minimum level, which according to experts lead to skidding of planes.

The aviation regulator also issued a checklist for airlines and airport operators on August 9. It has said it will do an audit in two months and then every quarter to ensure the checklist is being followed to avoid skidding.