Wildlife management in the areas surrounding airports in the country remains a perennial issue as birds continue to pose a threat to the flight operations.
This is evident if one considers the statistics available with the Directorate General of Civil Aviation (DGCA) till June 2017, which suggest that 764 bird hits damaging 66 aircraft were recorded in 2015. The number went up to 839 with 103 damages the next year. In 2017 until June, 363 bird hit cases resulting in 72 damages were reported.
The Visakhapatnam international airport, which is under the purview of Ministry of Defence, is also no exception as 10 bird hits have been recorded in the last three months.
According to Colonel E. Raman of World Bird Strike Association, an offshoot of International Civil Aviation Association, a scientific approach is needed to manage the wildlife including the issues pertaining to bird strikes at airports.
Colonel Raman, who has done a research on this subject, has been working actively with airports across the globe. “As per norms, every airport should try to keep the areas within 3 km to 13 km surrounding it free of habitation. If it is not possible then certain active and passive approaches should be implemented,” he says.
Speed and damage
For any aircraft, the last 200 metres while taking off or touching down is the most crucial. “The flying speed of any commercial aircraft varies between 430 nautical mile to 450 nautical mile and the landing speed is in the range of 120 NM and 140 NM. All bird hits happen between 0 to 200 feet. If a bird hits an aircraft at that speed then it may result in cracking of the canopy to the engine losing power,” he explains.
According to Colonel Raman, if bird hits the engine of an aircraft, the cost of repair can go up to 2 million USD and the loss of time and money both for the passenger and the operator add up to it.
Why Vizag vulnerable
Primarily a defence airfield, the Visakhapatnam airport operates both civil and defence flights. With the Meghadrigedda in its vicinity, the airfield is surrounded by marshy land with thick vegetation. And this serves a safe nesting ground for many avian species.
Giving details about some active methods, Colonel Raman suggests that the vegetation can be cut to below 15 cm to avoid flowering which attract birds for they feed on insects. It will also not allow birds to nest. “Another issue that plagues Vizag airport is its uneven topography dotted by puddles, a safe breeding ground for snails which attract birds,” says a senior naval officer.
Bio-acoustics
Colonel Raman adds that active methods such as implementing bio-acoustics at airports can work wonders to keep the avian species away.
“Bio-acoustics is all about sounds which could be a siren or any sound that drives birds away from the flight path. It can be positive phonotaxis that attracts birds towards the sound which can move them away from the flight part or negative phonotaxis that scares the birds away, depending upon the requirements. These can be followed by culling or use of round-the-clock trained patrolling staff armed with shotguns or firecrackers,” he adds.