3 seconds to take off from tragedy
It can take up to three seconds for an aircraft that has nearly touched down to accelerate and take off again — an eternity to the Air India pilots who had no more than an instant to get their plane airborne on Saturday before it crashed.delhi Updated: May 23, 2010 01:35 IST
It can take up to three seconds for an aircraft that has nearly touched down to accelerate and take off again — an eternity to the Air India pilots who had no more than an instant to get their plane airborne on Saturday before it crashed.
Clues to the crash of Air India Boeing 737 in Mangalore while possibly trying to abort a landing — a theory now being offered — come from a similar disaster 20 years ago and 350 km to the east in Bangalore, reveals a perusal by HT of civil aviation records.
A new Indian Airlines Airbus A-320 went down short of the runway at Bangalore’s old HAL airport in perfect landing conditions, killing 93 people on February 14, 1990.
The pilots of the 1990 Indian Airlines disaster made a series of fatal errors just before landing. When they tried to abort the landing it was too late, a former civil aviation official associated with the 1990 disaster-probe told HT.
“Aviation technology has progressed a lot since then, but the split-second reaction to an aborted flight must still be picture perfect,” said the official. “Everything must work perfectly in that instant.”
The majority of aviation disasters worldwide have occurred during takeoff or landing. Go-arounds, as aborted landings are called in aviation parlance, are common and safe, involving a split-second decision, the sudden acceleration, raising wheels and rapid climbs.
In rare instances they can go wrong, if man and machine do not function like clockwork.
That may have happened in Mangalore — if the Serbian captain of the Air India Boeing was trying to take off again. Only an official invesigation will reveal if this was the case.
In 1990, the Civil Aviation ministry’s inspector of accidents concluded the pilot and co-pilot did not select a “go around” altitude of 6,000 feet, a normal procedure during a landing approach.
The pilots set their instruments at an altitude lower that the plane’s actual altitude, and the autopilot was disconnected. The aircraft went in an “open-descent mode”, which meant the engines went into idling. When the pilots realised they were short of the runway and tried to accelerate in that instant, the engines were running too slow. They did not get the three seconds they needed to accelerate and climb away.
The Airbus struck a golf-course embankment less than a km short of the runway, bounced over a ravine and a road, sheared off its engines and exploded in flames. There were 56 survivors. India initially said the A-320, manufactured by Airbus Industries, the European consortium, or its American-made Pratt & Whitney engines were faulty, an accusation that Airbus rejected.