Bird-hit cases at Indira Gandhi International Airport (IGIA) have reportedly come down over the past four years,with only nine incidents till June this year compared to 67 in 2008.
The Delhi International Airport Limited (DIAL) has attributed this steady decline to several measures it had adopted for keeping birds away from the airports periphery.
The airport operator has claimed that techniques such as high-pitch sound blasts and a cleanliness drive in and around IGIA have been gradually showing results 36 and 34 bird-hits in 2010 and 2011,respectively.
Vehicles mounted with scarecrows and devices that periodically emit high-pitched distress calls patrol the area. They also use acoustic guns that fire high-frequency soundwaves to shoo away birds from the runway.
Currently,airports around the world use this system that emits electronic sounds,distress and alarm calls and predator attack cries to keep birds away from their vicinity,but it proves ineffective when planes gain height and move away from airport.
Most of the bird-hits occur when the aircraft is either gaining altitude or descending for landing. A study says the majority of bird-hits take place up to 500 feet from the ground level.
But DIAL CEO I Prabhakara Rao said: The methods have proven to be exceptionally successful. This is illustrated by the reduction in the number of bird-hit incidents over the past few years.
Besides,80 bird-chasers and 12 sharpshooters have been divided into teams and they work in shifts on the operational runways.
Garbage disposal in the open and in drains has been banned within a 10-km radius. Birds,especially scavengers,flock to garbage mounds and risk being sucked into aircraft jet engines during take-off and landing.
The grass near the runways are mowed periodically to maintain a height of six inches in accordance with the International Civil Aviation Organisation (ICAO) standards so that insects lay hidden from the birds.
A study by aircraft manufacturer Airbus says theres a 41 per cent chance of a planes engine,nose and windshield getting damaged in the event of a bird-hit. While chances of fuselage or wings getting damaged is just seven per cent,it stands at three per cent for landing gears and one per cent for the tail.