Recent development in aviation services in Kunming is being badly affected by the hidden dangers of unforeseen bird strikes. In fact, one-third of the maintenance cost of Kunming International Airport is taken up in its prevention.

According to the vice-director of the airport office, Wang Lin, the problem is locally created.

"Pigeons fed by farmers who live around the airfield are dangerous to the safety of the airplane service." As recently as January, two planes were badly damaged by flying pigeons while they approached for landing at Kunming International Airport. The cost of the damage was said to be in excess of 1 million yuan (US$120,664) for the airline company.

The bird strike phenomenon seems to be making a serious impact on world aviation services. According to the World Bird Strike Association there are 607 accidents caused in such a manner every year in Japan with over 150 strikes causing accidents at Kennedy International Airport each year. In China, 170 bird impact accidents were reported in civil aviation airports between 1991 and 1997.

The problem in Kunming, and its frequency, appears to be a geographic phenomenon caused by the migration of birds from the north of China. Situated in Yunnan Province, a southwest highland area of China, the weather tends from mild to warm and attracts flocks of migratory birds. Unfortunately for aviation services there, the airport is located en route of the migratory path. According to the bird dispersal team that monitor activity at the airport, there are 60 different kinds of birds passing overhead, with more than 30 kinds remaining in the area for some time.

The team invariably adopts a system that drives the birds from the airfield flight path and attempts to do no harm. Some are caught in nets and released at a later date, while others, such as grass owls, are kept for protection. Six grass owls were caught by the team this January.

Birds that do stay in the area surrounding the airfield do so because of the specific conditions of the airport as well as the surrounding natural environment.

While Kunming develops, the city creeps closer to the airfield and as the crow-flies the distance between the two is now only 6.6 kilometers. According to research conducted at the airfield office, 67 percent of people taking part in agricultural production, and 7 percent of migrant workers are conducting breeding and slaughtering. Roughly 41 percent of people litter in the area, which attracts the significant attention as food for the birds. Hundreds of Larus ridibundus, or black headed gulls, swarm a slaughterhouse only two kilometers from the airfield. According to the bird team, they frequently have the misconception that the airfield is a lake.

"We have to spend 800,000 to 1 million yuan (US$96,000 to 120,664) to drive the birds from the airfield each year." Zheng Yuming, section chief of the airfield construction office, said that the bird dispersal team uses a bird control vehicle, a net, noise-making devices, racket bombs and automatic gas exploders to manage bird problems in the area.

The airport has invested 2 million yuan (US$241,328) on this equipment. Now the noise-making device, which cost them 1.8 million yuan (US$217,000), is redundant because of age. The net, on average nine kilometers long, is replaced every three months. As racket bombs are the most effective way to rid the area of birds, 200 bombs are used nearly every day, with that number rising up to 300 or 400 in the winter. The problem is that the racket bomb programs cost around 360,000 yuan (US$43,000) annually. Another device is the remote control eagle that the team intends to purchase at a cost of US$30,000. This is why the maintenance budget allocates one-third of its total to the activity.

Recently, the Civil Aviation Administration of Yunnan invested huge money to bird control as well as in entrusting Yunnan Institute of Environmental Science to conduct research on the topic and area surrounding the airfield. Expert opinion suggests that the bird's food source should be either eliminated or drastically reduced. But with city development, there is pressure on the local city government to improve the airport area. Garbage disposal plants, slaughterhouses and fish processing factories should be re-situated if the problem is to see a successful solution.

"Pigeons are more dangerous than other birds," says Chen Guoli, leader of the bird dispersal team. There are more than 3,000 pigeons fed by villagers who live near and around the airfield. The problem is they are no longer afraid of humans or airplanes. They have a flying height of 30-50 meters which poses a real problem for aircraft takeoffs and landings. Statistically, more than 27 percent of people who feed pigeons are unaware of the problems the birds can cause to aircraft. Seven accidents have happened since 2002, to a huge cost to the economy, caused by flocks of pigeons.

Kunming is one of the five biggest international airfields in China. More than 200 airplanes take off and land there daily, with that number increasing to 400 during the holidays, especially during the three Golden Week' holidays of Labor Day, National Day and the Spring Festival.

(China.org.cn by Wu Nanlan February 17, 2003)