Since aircraft bird strike hazard is greatest at low altitudes (because that is where bird activity is most heavily concentrated) and at or near airports (because that is where the greatest concentration of aircraft is found), much of the focus on bird hazard management is on airports.
Operators of aircraft have a reasonable expectation that any bird hazard which may exist at an airport that they utilise will be controlled to a level which eliminates exceptional risk. Many States have detailed guidelines and compliance procedures to ensure that their airports achieve this but, despite the existence of related ICAO SARPs, there is no uniformity of achieved standards. This article summarises the main principles of an appropriate management approach for airport operators.
Principles of Effective Risk Management
The extent of a bird hazard at any particular airport location is widely variable. While there are many potential solutions and strategies available, not all are necessarily relevant to the particular circumstances of a specific airport. The most important action, upon which any risk management strategy must be founded, is knowing the nature of the (unmanaged) hazard. This may vary by time of day and seasonally and must be related to to the likely pattern of aircraft movements. Once a risk management plan is in place, it must be recognised that it is still necessary to monitor proactively for any detectable change in the assumptions upon which the plan was based. This is necessary in order to try and avoid complete reliance upon the reaction to an increase in the level of a recorded hazard as the trigger for any modification to the plan.
As with all risk management, an Safety Management System approach to risk management is essential. The activity must be founded on accountability, co-operation between stakeholders, proper documentation and an effective review procedure. All this needs to be facilitated by human and financial resources compatible with the task.
The one aspect of risk management, which is similar for all airports, is maintaining a reliable record of the hazard remaining despite the implementation of the risk management plan. In respect of actual bird strikes to aircraft, this is a requirement included in ICAO SARPs. Liaison with Operators is likely to be necessary to ensure full data capture and to exclude double counting. It is also important to keep records of changes to the risk mitigation actions in place under the risk management plan, so that the effects on the level of residual hazard recorded can be monitored.
It is likely that many larger airports will need the services of specialist advisers to assist in the initial preparation and ongoing review of the risk management plan.
Many of the ‘tools’ at the disposal of airport operators will find at least some place in any risk management plan but not necessarily to the same degree. These are essentially considered in three categories:
- Airport Habitat Management - grass and surface water (including transient accumulations) management, exclusion of roosting opportunities in buildings and trees within the airport perimeter
- Airport Locality Habitat Review (i.e. that area beyond the airport perimeter where bird attractants or related bird activity have the potential to directly affect the operational safety of aircraft using the airport) - note the ICAO definition of a 13km radius circle around the airport.
- Active on-airport control systems - bird activity monitoring, bird deterrence methods, ATC alerting channels
The selection of a balance of appropriate risk management methods will depend not only on the apparent effectiveness of deterrence of birds, but often on an understanding of any particular reasons why given species are present. See for example A biological battle against the thousands of garden chafers that attract large numbers of gulls during the summer season at Rygge air station, Norway
- ICAO Annex 14
- ICAO Doc 9137: Airport Services Manual Part 3 - Wildlife Control and Reduction, 4th edition, 2012
- ICAO Electronic Bulletin: 2008 - 2015 Wildlife Strike Analyses, 2017
- ACRP Report 145: Applying an SMS Approach to Wildlife Hazard Management, R. DeFusco et al. (Transportation Research Board, US), 2015
- Wildlife Control Procedures Manual, Transport Canada TP11500E (2002)
- Sharing the Skies Transport Canada TP 13549E second edition 2004
- UKCAA CAP 772 - Wildlife hazard management at aerodromes;
- AC 150/5200-33B: Hazardous Wildlife Attractants On or Near Airports, FAA, August 2007
- Wildlife Hazard Management at Airports FAA (2005)
- ACRP Report 32: Guidebook for Addressing Aircraft/Wildlife Hazards at General Aviation Airports by E. C. Cleary & A. Dickey (Transportation Research Board, US, 2010)
- The Fight against the Wild Life Hazard in France
- Airport Practice Note 6 'Managing bird strike risk', by the Australian Airport Association, September 2015