Runway ends at Kozhikode Calicut International Airport (CCJ), where Air India Express Boeing 737-800 was involved in a fatal runway excursion Aug. 7, were adjusted to create more runoff space for aircraft in 2019, an Airports Authority of India (AAI) document shows.

But the moves stopped short of recommendations made following a similar accident in 2010.

The changes, detailed in a February 2019 AAI Aeronautical Information Service update, show that the declared distances for landings and takeoffs on Runway 10/28, Calicut’s only runway, were reduced 160 m (525 ft), to 2,700 m. The modifications, which included installing red lights to designate the new runway ends but no other physical alterations to the runway surface, created 240 m of designated runway safety area at the end of each runway, factoring in existing overrun area.

Safety measures at the airport, which is set atop a hill and has downward slopes just beyond each runway overrun area, will be one of many areas scrutinized during the Air India Express Flight 1344 (IX1344) investigation.

Flight IX1344, repatriating passengers amid the COVID-19 pandemic, was carrying 184 passengers and six crew en route from Dubai. The pilots initially attempted to land on CCJ’s Runway 28 at about 1910 local time, India Directorate General of Civil Aviation (DGCA) director general Arun Kumar said.

“They could not land, and they asked for the other [runway end],” Kumar told CNN International.

After breaking off the initial approach, the flight was cleared for an Instrument Landing System (ILS) approach to Runway 10 at 1937 local time. The plane touched down at about 7:41 p.m. local time, well past the expected landing zone.

“The preliminary information that we have, they landed more than 3,000 ft. down the runway,” Kumar said. “They should have landed before 1000 feet … exact numbers will come out from the flight data recorder.”

The aircraft ran past the runway end and down an embankment beyond the designated runaway safety area. Its main fuselage broke into two pieces and the tail section separated from the rest of the airframe. Both pilots and 16 passengers were killed.

The area’s reported weather around the time of the accident included scattered clouds at 1200 ft. and below, rain, winds from 240-260 deg at 11-12 kt, and visibility of 2000 ft.

CCJ is one of three so-called “tabletop” airports—featuring runways atop flattened hills—with commercial service in India. Another, Mangalore International Airport, was the site of the only other Air India Express fatal accident, in May 2010, when a 737-800 ran off the runway end following continuation of an unstable approach. Investigators determined the flight landed long, and the pilots could not prevent the aircraft from running past the runway end, through a 90 m runway safety area, and down a steep slope. The aircraft broke into three pieces and 158 of 166 onboard were killed.

Among investigators’ findings: safety at tabletop airports could be enhanced by eliminating downward slopes beyond runway ends, and installing Engineering Material Arresting Systems (EMAS), the October 2010 final report on the probe said.

“As per worldwide data published by ICAO, most of the accidents occur during landing and take-off phases, with a large number of runway excursions and aircraft overrunning into the overshoot area,” the report said. “Considering the large momentum of these aircraft, a downward slope in the overrun area can worsen the outcome. It is therefore recommended that such downward slopes … be brought to the same level of the runway surface.”

Indian officials considered an EMAS for both CCJ and Mangalore based on the 2010 recommendations. But they determined enlarging the runway overrun areas by re-designating part of the runway surface as safety area and reducing the published, declared takeoff and landing distances was a more prudent approach.

“Provision of EMAS at Mangalore & Kozhikode were examined by AAI in consultation with DGCA,” India Minister of Civil Aviation Hardeep Singh Puri wrote on Twitter Aug. 10. “Considering the complexities of post installation maintenance & issues related with immediate replacement of product (in case of damage to EMAS) in such a critical safety area … it was then felt that the installation/provision of EMAS may not be suitable.”

The aircraft involved in the most recent accident, registered as VT-AHX and manufacturer serial number 36323, was delivered new to Air India Express in November 2006.

India’s Aircraft Accident Investigation Bureau and the DGCA are participating in the investigation. Both the flight data and cockpit voice recorder have been recovered, Kumar said.

source: Aviationweek