scope:

GENERAL

On 7 September 1908, while piloting the Wright Flyer, Orville Wright had what is believed to be the first collision between an aircraft and a bird, what is now known as a bird strike. Less than four years later, on 3 April 1912, at Long Beach, California, Calbraith Perry Rodgers, the first man to fly an aeroplane across the United States, became the first person to die as the result of a bird strike. His Wright Flyer became entangled with a gull that jammed the aircraft's controls, causing it to plunge out of control into approximately 1.5 m of sea water. The frail structures and power plants of the early aeroplanes meant that they were susceptible to bird strike damage. Fortunately, their slow speed gave pilots and birds/wildlife plenty of time to take any evasive action necessary.

Development of aircraft progressed to the point that they were robustly constructed and, consequently, more resistant to bird strike damage. Nevertheless, serious bird strikes did occur to such aircraft, usually involving the cockpit, the windshield and surrounding structure. Occasionally, injuries to flight crew did result from these bird strikes. During the 1950s, many metal, propeller-driven aeroplanes were gradually replaced by the faster and more efficient early jets; however, today, well into the 21st century, many propeller-driven aircraft are still in active flight operation.

Ironically, just at the dawn of jet passenger travel, two accidents involving propeller-driven airliners caused the aviation industry to more closely examine the danger that bird strikes pose to aircraft. Both occurrences involved a relatively new type of aircraft propulsion system, the turboprop. The first accident took place on 4 October 1960 at Boston's Logan International Airport. The aircraft, a Lockheed Electra L188, struck a flock of starlings (Sturnus vulgaris) just as it became airborne. The birds were ingested into three of the aircraft's four engines, causing the aircraft to lose power, stall and crash into the harbour. Of the seventy-two passengers and crew on board, sixty-two died. Two years later, on 23 November 1962, a Vickers Viscount struck a flock of Whistling Swans (Cygnus columbianus) over the State of Maryland, while flying at 6 000 feet. One of the horizontal stabilizers was penetrated by a swan, weakening the structure and causing it to separate from the aircraft which subsequently crashed and killed all on board. This crash resulted in the bird impact criteria for horizontal stabilizers being raised to eight kilograms (8 kg).

With the proliferation of jet aircraft and the increases in traffic that occurred throughout the 1960s and 1970s, modern jet-powered transport aeroplanes, with their greater speed, were seen to be at greater risk than their propeller-driven predecessors. Newer generations of aircraft continued to come into service, servicing ever increasing traffic needs and replacing older and less efficient aircraft. In many parts of the world, successful wildlife conservation has lead to increasing numbers of birds and other wildlife that are known to represent a risk to aviation. There is also increasing recognition that birds are not the only wildlife species to pose a threat to aviation safety. Some species of mammals and reptiles also pose a serious threat to aircraft safety. To adequately address the wildlife aircraft strike problem, wildlife/bird control on and around an airport should be expanded to include flying and terrestrial mammals and reptiles. Due to growing traffic, comprised of greater numbers of quieter aircraft, and the increase in wildlife populations, greater effort is required to control and monitor wildlife movements on and within the vicinity of airports. In addition, the cost of downtime for inspection and repair of aircraft following bird/wildlife damage or suspected bird/wildlife damage is significant. The additional costs and disruption as a result of aborted flights, rescheduling of aircraft passengers and air cargo, transfer of passengers to alternative means of transport, overnight accommodation at the expense of the aircraft operator and the deleterious effects on connecting flight schedules that can be significant and damaging to airline operating budgets and public goodwill (the passenger experience) are also major factors in the cost of a bird strike. It is apparent that data on bird/wildlife strikes need to be collected in order to better understand the dynamics of the bird/wildlife strike problem. The ICAO Bird Strike Information System (IBIS) is ideally suited to this task. A complete description of IBIS can be found in the Manual on the ICAO Bird Strike Information System (IBIS) (Doc 9332). IBIS provides analyses of bird/wildlife strike reports received from States. An analysis of this data reveals that approximately ninety per cent (90%) of bird/wildlife strikes occur on or in the immediate vicinity of airports.

The analysis of bird/wildlife data in respect of bird strikes and observations and monitoring of bird/wildlife activities can reveal trends that will assist airport authorities to recognize areas of concern which should be addressed through a well-managed wildlife control programme. Bird/wildlife strike statistics can also be analysed to determine those times of year or day when bird/wildlife control is needed the most.