A Jet Airways flight to Mumbai, with 160 passengers on board, had a close shave when the pilot took off ignoring a Met office warning and almost got trapped in a monstrous thundercloud.
The over-17-km-tall column of cloud bore charged particles, some of more than 1,000 volts, enough to electrocute the plane.
“There was no damage to the aircraft,” said a Jet Airways official. He claimed that the airline did not have any more information about the incident on April 12.
The flight was scheduled to take off around 6pm, said an airport official. “Around 4.50pm, the gigantic thundercloud was detected over the airport and an alert was sounded.”
The cloud was 750 metres above ground level and was moving from the north-west to the south-east. “The Met office had warned the pilot about the cloud 30 minutes before take-off,” said the official.
Around 20 flights were scheduled to take off around that time. “None of the planes, barring the Jet flight, took off due to the inclement weather condition,” said the official.
The Jet aircraft flew dangerously close to the cloud. “The pilot’s expertise and experience helped him steer the plane past the cloud,” he said. It was “a narrow escape”.
The cumulonimbus cloud was of the type that causes Nor’westers. “Met officials told us that the cloud’s movement was very unusual on that day,” said the official. Such clouds normally move from the south-east to the north-west. The cloud over the airport drifted away around 7.30pm.
The air safety wing of the directorate-general of civil aviation (DGCA) has started an inquiry into the incident.
“We have sought a detailed report on the weather condition on April 12, along with satellite and radar pictures of the area from the Met department of Calcutta airport,” said a DGCA official on Sunday.
Sources in the directorate said the probe has been undertaken to determine whether the pilot ignored the warning or it was not communicated to him properly.
Errors by pilots and communication officers of the Air Traffic Control have resulted in a number of narrow escapes. Over the past 15 months, there could have been at least eight mid-air collisions over Calcutta, when planes came within 0.6 km (2,000 ft) of each other.
Aircraft are equipped with a Traffic Collision Avoidance System, which alerts pilots if another plane comes within 40 nautical miles (74.08 kilometres) of it. But the presence of the system is not a guarantee against collision.