Eyewitnesses said that flames could be seen coming out of the twin-engine aircraft’s left engine as it roared over Narefat, Koteshwor while making its final approach.

Bimlesh Lal Karna, Chief Air Traffic Controller at TIA, said that a bird slammed into the jet’s left engine at 12:05 pm at a height of 500-600 ft over the southern end of the runway.

According to him, the pilots declared “pan-pan” while making its final descent and requested priority landing clearance immediately after it suffered the bird hit.

The term “pan-pan” repeated thrice by a flight crew member means a state of urgency with no imminent danger to life or aircraft. The crew declares “pan-pan” when they require help to land safely.

Karna said that an airline engineering team was inspecting the stricken aircraft and it would be cleared to fly after the necessary maintenance was done.

Last March, a Malaysia Airlines jet was hit by a flock of birds while landing at TIA.

More than 82 bird hit incidents during take-off or landing have occurred at Kathmandu’s airport since 1990. Three of them involving a Thai Airways Airbus A300 in October 1996, a Bangladesh Biman DC-10 on September 2, 2010 and a Sita Air aircraft in September 2012 resulted in major damage.

TIA has a 52 percent incidence of bird strikes compared to other airports, officials said. According to experts, aircraft are significantly at risk during take-off and landing as 90 percent of birds fly below an altitude of 2,000 ft.

The polluted Bagmati and Manohara rivers, paddy cultivation, trees and landfill sites which are situated within a 15-km radius of TIA attract birds to the area.

Experts said that when a bird weighing 3 kg slams into an aircraft at 150 km per hour, the impact is equivalent to being struck by a 1,800-kg hammer on a 1 square foot area.

A Civil Aviation Authority of Nepal report shows that there are 39 species of birds in the area around TIA. Among them, five are large types, 10 are medium-sized and 24 small-sized.

The black kite is a major threat. Bird strikes happen mainly during the winter season, which is the bird migration season in the Kathmandu valley.