Chapter 11 — Solutions — Air Operators


Whether their operations are private or commercial, whether they operate one singleengine aircraft or several hundred large jet aircraft, air operators stand to incur significant costs from fleet damage caused by wildlife strikes. Yet there are many ways the industry can reduce both the probability and severity of these strikes, including a range of actions that ensure a measurable, positive effect on companies’ bottom lines. Even a ten-percent reduction in the number of damaging wildlife strikes would reduce the cost to the North American aviation industry by at least USD$50-million.

This chapter offers information on the role air operators play in reducing the likelihood and seriousness of wildlife strikes. Presented in a series of checklists, the information addresses diverse types of commercial and business-aircraft operations. As a result, some checklist items may not be applicable to all operators. The checklists apply to general flight planning and operating principles, then specific planning and operating techniques. For ease of use, the lists are presented in order of phase of flight.

Roles and responsibilities

Air operators have legal responsibilities defined in the Canadian Aviation Regulations (CARs), Part VI and VII, including:

  • flight-operations procedures,
  • flight-dispatch systems,
  • aircraft-maintenance procedures,
  • safety-management systems, and
  • employee-training requirements.

For details, the CARs can be readily accessed on the Transport Canada website:

Civil and criminal-code legal obligations also apply, requiring air operators to conduct business safely. Failure to meet these obligations may result in serious legal and financial consequences (See Chapter 1).


Reducing the probability and severity of wildlife strikes

There are three areas where air operators should concentrate their efforts:

  • Standard Operating Procedures (SOPs),
  • employee training and awareness, and
  • reporting of wildlife strikes.

Standard Operating Procedures

Wildlife-hazard-specific SOPs should be developed and included in company publications, addressing the following areas:

  • flight operations (pilots),
  • flight dispatch (flight planning and flight following),
  • aircraft maintenance, and
  • ramp operations (aircraft ground handling).

Flight operations and flight dispatch

Flight operations and flight dispatch are closely related disciplines that use common SOPs. The following sections offer procedures to help reduce wildlife-strike probability and severity when included in company manuals.

General operating principles

Flight operations and dispatch wildlife-hazard SOPs should promote flight planning and aircraft-operating techniques that address the following unique aspects of commercial and business aviation:

  1. Operating speeds for business and commercial aircraft are higher than for light general-aviation aircraft. Therefore, less time is available to observe wildlife. Higher speeds also increase impact force and the potential for damage in the event of a bird strike.
  2. The time available to observe wildlife activity is restricted by the intense workload during critical phases of flight.
  3. The physical size of these aircraft increases the likelihood that encounters with flocks of birds will lead to damage at multiple locations on the aircraft.
  4. These aircraft are larger and less manoeuvrable, making it more difficult to take evasive action when birds are encountered.
  5. Aircraft size, cockpit location and windshield size restrict visibility from cockpits, limiting the ability to see birds and mammals.
  6. Requests for alternate runways to avoid bird concentrations at busy airports can lead to significant delays.
  7. Commercial and business aircraft operating from busy airports are subject to tight schedule constraints; arrival and departure flexibility is limited when attempting to avoid wildlife activity.
  8. In takeoff phase, commercial and business aircraft are frequently governed by published departure procedures and noise and traffic-management requirements, limiting the ability to adopt alternate flight paths to avoid areas of bird activity.
  9. In approach and landing phase, constraints are similar to those for takeoff and climb. Flight profiles are governed by published approach procedures. At large airports, sequencing high volumes of traffic further restricts flight-path flexibility.
  10. Aircraft accident statistics show a high number of accidents during rejected takeoffs among business and commercial aircraft. The decision to reject takeoff is time-critical; the success of the manoeuvre is dependent on precise crew coordination. Multiple strikes to more than one engine are likely to result in rejected takeoffs.
  11. A number of bird-strike incidents have involved damage to more than one engine or aircraft system, including:
    • B737—Calgary 1993,
    • B747—Montreal 1998,
    • B727—Houston 1998.
      Given the rise in aircraft numbers—particularly of twin-engine aircraft—andgrowth of some bird populations, serious damage from an airborne encounter with flocks of waterfowl is a distinct possibility
  12. Rotary-wing operations are particularly challenging because:
    • The majority of helicopter flight operations are conducted at very low altitudes,typically below 500 ft AGL.
    • The pilot’s concentration is focused on maintaining terrain clearance whilecompleting the assigned task; there is little or no time available to watch for birds.
    • Even during the cruise phase of flight, most helicopters remain close tothe ground.
    • Helicopter operating speeds are generally lower than fixed-wing aircraft, butbird-strike certification standards—even for Transport Category helicopters—are not stringent (see Chapter 5).
    • Helicopters are more of a disturbance to bird colonies than fixed-wingairplanes; strike risk is therefore increased when birds are flushed into the air.
    • There is significant risk of birds penetrating the windshield and causing seriousinjury and incapacitation.


Air operator general flight planning and operating principles

All flights should be planned and executed according to proven wildlife-strike risk reduction principles and techniques:

  1. Plan your flight to operate at the highest possible altitude; the probability of bird strikes decreases dramatically above 3,000 ft AGL, and emergency situations are more challenging at low altitudes.
  2. The best way to reduce the probability of a bird strike is to maximize rate of climb on departure. Jet-engine aircraft should use the ICAO Vertical Noise Abatement Profile ‘A’ (VNAP ‘A’). The benefits are:
    • low aircraft speed (V2+10), which reduces impact force;
    • rapid climb rate to get above 3,000 ft AGL as quickly as possible; and
    • climb-out occurs as close to an airport boundary as possible, where bird activityis managed.
  3. Reducing speed also limits the severity of bird strikes—impact force increases as the square of speed (see Chapter 12, Table 12.1).
  4. Use extreme caution if accelerating above 250 kts below 10,000 ft MSL (mean sea level). (In some jurisdictions, aircraft may accelerate above 250 kts at altitudes over 3,000 ft MSL. However, Canadian Aviation Regulations were recently amended to limit airspeed to 250 kts or less at altitudes below 10,000 ft MSL.) These higher speeds increase the probability of a bird strike, since climb rate is reduced while accelerating, thereby increasing time spent in altitudes where birds are more likely to be present. The potential severity of a strike also rises, since impact force increases. Bird strikes above 3,000 AGL occur less frequently, but the majority of these strikes involve larger birds that incur frequent and significant damage.
  5. Use landing lights at all times when operating aircraft below 10,000 ft AGL.
  6. Avoid planning and flying routes:
    • over areas known to attract birds, such as sanctuaries, landfill sites and fishpackingfacilities;
    • along rivers and the shorelines of lakes and oceans, particularly at minimumaltitude. Birds, as well as pilots, use these geographic features as navigational aids;
    • over inland waterways and shallow estuaries at minimum altitude. Largenumbers of gulls, wading birds and waterfowl frequent these areas throughoutthe year. These species of birds may make regular flights at dawn and dusk;
    • at minimum altitude over geographical features such as offshore islands,headlands, and cliffs. These areas are frequently used as colonial nesting sites.
  7. The following suggested operating techniques can help reduce the probability and severity of bird and mammal strikes to rotary-wing aircraft:
    • Always wear a helmet with a visor. The greatest immediate danger to helicopterpilots following windshield penetrations is loss of vision from flying debris.
    • Ensure that flight crews regularly review emergency procedures,particularly autorotations.
    • If a bird strike occurs, have the helicopter inspected carefully prior to the nextflight, preferably by an aircraft maintenance engineer (AME). Remember thatdamage to main or tail rotors may not be easily detected.
    • Rotary-wing aircraft are capable of accessing a range of environments, onestablishing helipads in remote areas—information air operators may wish toinclude in operations manuals.
  8. While most bird species are active primarily during the day, bear in mind that many birds such as owls and migratory waterfowl regularly fly at night.
  9. Birds tend to be more active at dawn and dusk. Many species have predictable daily flight patterns; they travel to feeding sites at dawn and return to roosting sites at dusk.
  10. In Canada, bird-strike risk peaks at three times throughout the year:
    • during spring migration in March and April;
    • in July and August, when many inexperienced young birds are present, and theflying abilities of adults may be impaired due to molting; and
    • during fall migration in September and October.
  11. Be aware that a significant percentage of the North American Canada Goose population remains in urban areas—and therefore often in the vicinity of many airports—throughout the year.
  12. On hot summer days, many bird species—such as raptors and gulls—harness thermals and soar to considerable heights.
  13. Birds of prey have been reported to attack aircraft.
  14. Bird size can be estimated by observing the wing-beat rate; the slower the beat, the larger the bird and the greater the potential for damage. Remember: large and flocking birds present considerable risk to aircraft.
  15. Be aware that birds may not hear quiet aircraft in time to avoid collisions.
  16. If you encounter birds, the most effective evasive action may be to climb above them while maintaining a safe speed. Biologists have observed that some birds break downwards when threatened. Other recent studies indicate that some birds may view aircraft as immobile objects, and turn slowly away when at a perceived safe distance.
  17. If bird strikes occur, pilots should:
    • maintain control of the aircraft. Remember that the sound of a bird strike maybe disproportionately worse than the resulting damage;
    • refer to appropriate checklists and carry out any applicable emergency procedures;
    • assess damage and its effect on aircraft landing performance;
    • land at the nearest suitable airport considering weather, facilities andemergency services;
    • enlist the assistance of ATS providers and airport emergency personnel;
    • consider an aircraft controllability check before attempting a landing ifstructural or control system damage is suspected;
    • remember that control-surface damage and flutter are not readily apparent onfly-by-wire aircraft, which lack direct linkage from control surface to pilot. Asa result, there is no physical feedback of aerodynamic flutter, while electroniccontrol-position indicators lack sufficient fidelity to depict surface flutter;
    • follow approved procedures contained in the pilot’s operating handbook andaircraft operating manual if the windshield is broken or cracked; and
    • slow the aircraft to reduce wind blast if the windshield is penetrated. Considerthe use of sunglasses or smoke goggles to protect your eyes from wind,precipitation and flying debris.
  18. Following a bird or mammal strike—and before the next flight—have the aircraft thoroughly inspected according to approved company maintenance procedures.


Planning and operating techniques

Some suggested planning and operating techniques that can reduce the probability and severity of wildlife strikes, and that should be included in any air operator’s Flight Operations Manual (FOM) and Aircraft Operating Manual (AOM), are listed below:

Flight planning

  1. During the flight-planning process, review available information on potential and known bird hazards:
    • at your departure point,
    • on your flight route,
    • at the arrival airport, and
    • at any alternate airport planned for the destination or enroute.

      Bird-hazard information can be obtained from:  
    • airport documentation contained in the Canada Flight Supplement (CFS)or the equivalent publication for the country of flight;
    • NOTAMs and, in some countries, specific bird-hazard information knownas BIRDTAMs;
    • Rules of the Air and Air Traffic Services Section (RAC) of Canada’sAeronautical Information Publication (A.I.P.)—particularly for seasonalbird-migration routes in Canada;
    • The Avian Hazard Advisory System (AHAS) Internet website (AHAS - for current bird movements.)
  2. When planning the route, employ strategies to reduce the probability of a bird or mammal strike.

Preflight preparation

  1. When approaching the aircraft, pilots should take time to observe wildlife activity in the immediate area.
  2. During preflight walk-around, pilots should be alert for signs of nesting birds in all airframe cavities and around the engines. Evidence of nesting peak nesting season, aggressive birds can have nests partly built in the time it takes pilots to have lunch.
  3. When obtaining the Automatic Terminal Information Service (ATIS) and airport information from ATS providers—or UNICOM—note any reports of bird or mammal activity.
  4. If possible, pilots should heat their windshields. As noted in the pilot’s operating handbook and aircraft operating manual, heat increases both windshield pliability and its ability to withstand bird impacts.
  5. Prior to engine start and during pre-flight reviews of aircraft-emergency procedures, flight crews should consider courses of action that may be necessary in the event of a wildlife strike.

Taxiing for takeoff

  1. Takeoff is a critical phase of flight; strike statistics show that 31 percent of bird strikes and 39 percent of mammal strikes occur during this phase (see Chapter 7).
  2. Pilots should be alert while taxiing for takeoff, noting any bird- and mammalactivity reports by ATS providers and other operators.
  3. While taxiing, pilots should report wildlife activity observed on ramps, taxiways and runways to ATS providers, UNICOM and other aircraft.
  4. Pilots must be especially vigilant when operating at airports that either do not have ATS providers, or have limited hours of ATS operation. Often, these airports have no formal wildlife monitoring or management. Prior to takeoff, it may be necessary to backtrack the length of the active runway to ensure there are no birds or mammals.

Takeoff and climb

  1. As noted above, the best way to reduce the probability of a bird strike is to maximize rate of climb on departure. Jet-engine aircraft should use the ICAO Vertical Noise Abatement Profile ‘A’ (VNAP ‘A’).
  2. While rolling onto the runway, pilots should prepare themselves mentally to deal with the consequences of a bird or mammal strike during takeoff. They must be aware of conditions that may affect their ability to either reject takeoff or continue flying under reduced aircraft performance. These include:
    • runway surface conditions,
    • weather, and
    • obstacles.
  3. Before commencing takeoff, check the runway once more for wildlife; many birds stand on concrete and asphalt surfaces to warm themselves and to gain a clear view of approaching predators.
  4. Pilots would be wise to remember that an aircraft taking off ahead of them may frighten birds and mammals into their flight path.
  5. If there is bird activity on the runway, be prepared to wait for wildlifemanagement personnel to clear them. If traffic and weather conditions permit, pilots should use another runway. Wildlife hazards should be treated like any other flight-safety hazard—if any doubt exists concerning safety, delay takeoff until conditions are right.
  6. Use landing lights during takeoff. Although there is no conclusive evidence that birds see and avoid aircraft lights, limited data and anecdotal evidence suggest that landing lights—particularly pulsed landing lights—make aircraft more visible to birds and provide more time for the animals to take evasive action.
  7. Aircraft weather radar are not effective as a means of warning birds, as they do not sense the low power emissions and frequencies of these units.
  8. Pilots should select engine ignition on for takeoff to enhance engine flameout protection when operating turbine-powered aircraft in the presence of birds.
  9. Should a bird or mammal strike occur during takeoff roll, a rejected takeoff is the safest course of action if prevailing conditions are appropriate. When safe, vacate the runway and shut down aircraft engines. Before continuing the flight, have the aircraft thoroughly inspected, preferably by an aircraft maintenance engineer (AME).
  10. Be prepared to adjust the climb route to avoid birds.
  11. If there is reported bird activity, pilots should plan to operate aircraft at reduced airspeeds to minimize impact force and aircraft damage.
  12. If there is an altitude band where birds are anticipated, climb through these altitudes as quickly as possible, using the manufacturer’s recommended best rateof- climb speed.
  13. The majority of bird strikes occur below 10,000 ft AGL, so continue to use landing lights during climb until above this altitude.



  1. Pilots should listen to appropriate enroute radio frequencies to obtain up-to-date information on bird activity from ATS providers and other aircraft.
  2. Pilots should report all hazardous bird movements to ATS providers and other aircraft.

Approach and landing

  1. Approach and landing is a critical phase of flight. Strike statistics show that 39 percent of bird strikes and 58 percent of mammal strikes occur during approach and landing (see Chapter 7).
  2. Pilots should obtain the latest information on any bird and mammal activity from ATS providers, ATIS, UNICOM and other aircraft.
  3. Pilots must be especially vigilant when operating at airports that either do not have ATS providers, or have limited hours of ATS operation. While these airports often do not feature wildlife monitoring and management, it is nonetheless prudent to request that airport personnel inspect the runway environment to ensure it is clear of hazardous wildlife. Watch for wildlife activity throughout approach and landing.
  4. Plan aircraft descent and approach routes to avoid areas that attract birds.
  5. During descent and approach in areas with high bird activity, reduce airspeed to diminish the severity of potential bird strikes.
  6. If bird activity is reported at particular altitudes, pilots should use a higher rate ofdescent—without increasing speed—to minimize exposure to potential bird strikes.
  7. Wildlife hazards during approach and landing should be treated like any other flight-safety hazard—if any doubt exists concerning safety, delay landing until conditions are right.
  8. If birds are encountered on approach, pilots should consider a go-around and a second approach, but only if the go-around can be initiated without striking birds after power is increased. This strategy may allow birds to disperse before the aircraft’s return. Please note that several bird-related incidents and fatal accidents have resulted from pilots initiating a go-around when the aircraft was in a low energy state and likely capable of a safe landing.
  9. Use landing lights during approach and landing to make the aircraft more visible to birds.
  10. Pilots should report all bird and mammal activity to ATS providers, UNICOM and other aircraft.


  1. If aircraft have struck birds or mammals, or if pilots suspect strikes may have occurred:
    • report incidents to company maintenance personnel and have aircraft thoroughlyinspected prior to the next flight;
    • report incidents using approved company safety reporting systems; and
    • if required, report the incident to the Transportation Safety Board of Canada.
  2. Report all bird and mammal strikes to Transport Canada. In foreign countries, report to appropriate authorities. See Appendix C for copies of reporting forms and details on bird- and wildlife-strike reporting processes. When completing bird- and mammal-strike reports consider:
    • providing further useful information: photograph all bird remains and damageand send the photographs to Transport Canada along with the report.
    • if unable to identify the struck species, collect all remains—no matter howsmall—and contact Transport Canada to arrange for assistance (see Appendix Cfor contact information).


Aircraft maintenance

Aircraft maintenance SOPs should stress:

  • the importance of thorough inspections following a wildlife strike, and
  • reporting details of wildlife-strike damage and repair costs to the air operator’s flight-safety organization.

Maintenance inspection checklists used following wildlife strikes should:

  • adhere to applicable air-operator wildlife-strike reporting procedures and ensure that the incident is reported to Transport Canada;
  • ensure that strikes have not damaged
  • or blocked engine intakes, exhausts, cooling and airflow ducts; and
  • landing gear, brake hydraulic lines, landing-gear downlocks and any landing gear switches;
  • ensure structural integrity if damage to airframe or control surfaces is suspected; minor exterior damage may disguise serious underlying structural damage;
  • include close inspection of turbine engines. In several incidents, basic visual inspections failed to reveal damage that affected subsequent flights;
  • note that rotary-wing aircraft are susceptible to main- or tail-rotor damage that may not be easily detected;
  • encourage inclusion of additional useful information, such as damage photographs and bird remains that can be forwarded to air operators’ flight-safety departments;
  • in cases when struck species cannot be identified, request the collection and delivery of any bird remains—no matter how small—to air operators’ flightsafety departments (see Appendix C for contact information).

Ramp operations

In addressing removal of wildlife attractants from ramp areas, ramp-operations SOPs should stress the following:

  • immediate collection of all garbage—and particularly food waste—for storage in closed containers;
  • secure lids for all garbage containers;
  • ensuring garbage containers are kept closed;
  • commitment of ramp personnel not to feed birds and mammals, nor attract them to ramp areas; and
  • immediate reporting of all ramp-area wildlife activity to airport wildlifemanagement personnel.
Training and awareness

Through employee training and awareness, companies can foster cultures in which dangers posed by wildlife hazards are recognized and commitment can be built to reduce those hazards diligently on a daily basis.

Employee training

All employees of air operators should be trained on the risks and costs of wildlife strikes, reminding them of both the importance of company SOPs and the value of wildlife-hazard vigilance—measures critical to safety management and cost control.

Particular attention should be given to pilot training, preparing flight crews for the emergencies that often follow bird and mammal strikes. Some suggested training strategies are:

  • Annual pilot briefings and recurrent training that include reviews of recent wildlifestrike incidents within the company and the industry. These sessions provide opportunities to review typical wildlife-strike scenarios and the most appropriate procedures for addressing associated hazards.
  • Simulator scenarios involving aircraft-performance degradations and multiplesystem damage—such as that resulting from bird strikes—impress upon pilots both the potential seriousness of strikes and the proper application of approved aircraftoperating procedures in response. In another useful simulator scenario, one crew member is incapacitated as a bird penetrates the windscreen; the remaining crew member must complete all required emergency procedures including returning to land at a suitable airport.
  • Promotion of Crew Resource Management techniques (CRM) to ensure optimal use of cockpit resources in the event of a serious bird strike—particularly important when windscreen visibility is reduced as a result of a strike.

Employee awareness

While airline companies are under no specific obligation to make employees aware of problems associated with wildlife strikes, air operators are required by the CARs to disseminate safety-awareness material to employees. There are a number of practical and effective ways to communicate the wildlife risks to air-operator employees including:

  • regular publication of company wildlife-strike statistics;
  • posting wildlife-hazard awareness posters in strategic employee locations;
  • posting special bulletins to warn pilots of newly identified wildlife hazards;
  • issuing bulletins as migratory periods approach, reminding pilots of potential dangers and approved strategies to reduce the probability and severity of bird strikes;
  • using company safety publications to educate employees on wildlife hazards, as well as the latest developments in equipment design and procedures that reduce risk;
  • informing staff of the high costs associated with wildlife-strike damage; and
  • keeping a supply of Transport Canada wildlife-hazard education materials readily available for employee review.


Wildlife-strike reporting

As discussed in Chapter 7, one of the most serious deficiencies in the effort to avert the wildlife-strike problem is a lack of comprehensive strike statistics. It is estimated that only 20 percent of wildlife strikes are reported, due in part to the lack of a regulatory requirement to do so. Air operators already have the infrastructures through which safety trends are recorded—systems ideal for capturing and analyzing wildlife-strike statistics.

Air operators should consider expanding these systems to require flight crews and maintenance personnel to report all wildlife strikes. It is also critical that this data be shared to ensure the maintenance of a comprehensive, industry-wide, wildlife-strike database. This database could be employed to identify specific trends and promote development of effective solutions that mitigate risks.

Some suggested components of a wildlife-strike safety reporting system are listed below:

  • The safety-reporting system must be founded on the principle of non-punitive reporting of safety incidents.
  • Safety reporting-system data that is shared with other safety professionals must be presented in an anonymous form that obscures identity of the reporter.
  • Wildlife-strike data must be shared with other safety professionals such as Transport Canada and airport wildlife-management personnel.
  • Wildlife-incident report forms should mirror the Transport Canada Bird/Wildlife Strike Report form to ensure correct information is reported in a uniform manner.
  • Maintenance personnel should also have a means whereby they can report wildlifestrike damage to the wildlife-incident reporting system.
  • The safety reporting system should include wildlife-strike damage costs.
  • The safety reporting system should have a structured database that determines trends by facilitating long-term record keeping and analysis.



Air operators have a vested financial interest and a legal obligation to seek ways to reduce the probability and severity of wildlife strikes, focusing on:

  • effective Standard Operating Procedures (SOPs);
  • structured and regular employee training; and
  • a robust, non-punitive safety reporting system that captures wildlife-strike data and shares it with the aviation industry in an aggregate, anonymous form.
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