Chapter 10 — Solutions — Pilots
- Standards Branch
- Aerodromes and Air Navigation
- Wildlife Control
- Preface to the second edition
- How To Use this Book
- Chapter 1
- Chapter 2
- Chapter 3
- Chapter 4
- Chapter 5
- Chapter 6
- Chapter 7
- Chapter 8
- Chapter 9
- Chapter 10
- Chapter 11
- Chapter 12
- Chapter 13
- Chapter 14
- Chapter 15
- Production Team
- Colour Plates
- Roles and responsibilities
- Planning and operating to minimize wildlife risks
of Brian Losito
This Chapter discusses the role pilots play as stakeholders in an airport wildlifemanagement plan. Information is provided to heighten awareness among pilots and to describe actions that can be taken as part of an overall strategy to reduce the risk of strikes. While the information provided here is based on well-documented best practices, this chapter is not meant to supercede any procedures contained in approved pilot’s operating handbooks or aircraft operating manuals.
Pilots can reduce the probability and severity of bird and mammal strikes through prudent flight planning and the use of appropriate aircraft operating techniques. By observing and reporting wildlife movements to ATS providers and wildlifemanagement personnel, pilots can also help protect other aircraft operators.
Information is presented as a series of checklists comprising:
- general-pilot, flight-planning and operating principles,
- pilot-planning and operating techniques that apply to all aircraft types, and
- supplementary information that applies to specific classes of aircraft operation.
These checklists are presented in phase-of-flight order, from flight planning through to post flight. Pilots are advised to read the general checklists as well as those that apply to their specific classes of aircraft operation.
In Canada, the Aeronautics Act and Canadian Aviation Regulations (CARs) outline the legal responsibilities of the pilot in command of an aircraft, as well as standards for flight preparation and aircraft operation. Similar legislation exists in the United States and other jurisdictions around the world. For the purposes of outlining the applicable sections of Canadian legislation shown below, “pilot in command” is defined as the individual responsible for the operation and safety of an aircraft during flight time.
- Pre-flight information (CAR 602.71) The pilot in command of an aircraft shall, before commencing a flight, be familiar with the available information that is appropriate to the intended flight.
- Reckless or negligent operation of aircraft (CAR 602.01) No person shall operate an aircraft in such a reckless or negligent manner as to endanger or be likely to endanger the life or property of any person.
Where wildlife hazards are concerned, these regulations imply that pilots have a legal responsibility to both familiarize themselves with potential risks that may affect their flights, and operate their aircraft during all phases of flight in a manner that minimizes the probability and severity of wildlife strikes.
Pilot general flight-planning and operating principles
All pilots should plan and operate flights according to proven wildlife-strike risk-reduction techniques. The following strategies and observations apply:
- 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.
- Reducing speed also limits the severity of bird strikes—impact force increases as the square of the speed (see Chapter 12, Table 12.1).
Avoid planning and flying routes:
- over areas known to attract birds, such as sanctuaries, landfill sites and fishpacking facilities;
- along rivers and the shorelines of lakes and oceans, particularly at minimum altitude. Birds, as well as pilots, use these geographic features as navigational aids;
- over inland waterways and shallow estuaries at minimum altitude. Large numbers of gulls, wading birds and waterfowl frequent these areas throughout the 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.
- 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.
- 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.
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 the flying abilities of adults may be impaired due to molting; and
- during fall migration in September and October.
- 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.
- On hot summer days, many bird species—such as raptors and gulls—harness thermals and soar to considerable heights.
- Birds of prey have been reported to attack aircraft.
- 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; large, flocking birds are extremely hazardous.
- Be aware that birds may not hear quiet aircraft in time to avoid collision.
- 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.
If a bird strike does occur:
- Maintain control of the aircraft. Remember that the sound of a bird strike may be disproportionately greater than the resulting damage.
- Refer to checklists and carry out applicable emergency procedures.
- Assess damage and its effect on aircraft landing performance.
- Land at the nearest suitable airport.
- Enlist the assistance of ATS providers and airport emergency personnel.
- If structural and control-system damage is suspected, consider an aircraft controllability check prior to attempting a landing.
- Control-surface damage and flutter are not readily apparent on fly-by-wire aircraft, which lack direct linkage from control surface to pilot. As a result, there is no physical feedback of aerodynamic flutter, while electronic controlposition indicators lack sufficient fidelity to depict surface flutter.
- If the windshield is broken or cracked, follow approved procedures contained in the pilot’s operating handbook or aircraft operating manual.
- If the windshield is penetrated, slow the aircraft to reduce wind blast. Consider the use of sunglasses or smoke goggles to protect your eyes from wind, precipitation and flying debris.
Following a bird or mammal strike—and before returning to the air—have the aircraft thoroughly inspected, preferably by an aircraft maintenance engineer (AME). Pay careful attention to the following:
- Ensure the strike has not damaged or blocked the engine intake, exhaust and cooling and airflow ducts.
- Check landing gear, brake hydraulic lines, landing-gear downlocks and any landing-gear switches.
- If damage to the airframe or control surfaces is suspected, thorough inspections should be carried out by maintenance personnel to ensure structural integrity; minor exterior damage may disguise serious underlying structural damage.
- Turbine engines that have suffered bird strikes deserve careful attention. In several incidents, basic visual inspections failed to reveal damage that affected subsequent flights.
Planning and operating to minimize wildlife risks
The following sections summarize pilot flight-planning and operating techniques that have proven effective in enhancing safety and reducing wildlife risk.
Planning and operating techniques for all aircraft
Many techniques that minimize wildlife risk are common to all aircraft types and classes of operation.
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 known as BIRDTAMs;
- Aeronautical Information Publication (A.I.P.)—particularly for seasonal bird migratory routes in Canada.
- The Avian Hazard Advisory System (AHAS) Internet website: www.ahas.com for current bird movements.
- When planning the route, employ strategies to reduce the probability of a bird or mammal strike.
- When approaching the aircraft, observe wildlife activity in the immediate area.
- During preflight walk-around, be alert for signs of nesting birds in all droppings and straw littered on and around the aircraft. During peak nesting season, aggressive birds can have nests partly built in the time it takes pilots to have lunch.
- When obtaining the Automatic Terminal Information Service (ATIS) and airport information from ATS providers—or UNICOM—note any reports of bird or mammal activity.
- If possible, heat the windshields. As noted in the pilot’s operating handbook or aircraft operating manual, heat increases both windshield pliability and its ability to withstand bird impacts.
- Prior to engine start and during pre-flight reviews of aircraft emergency procedures, consider courses of action that may be necessary following a wildlife strike.
Taxiing for takeoff
- 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).
- Be alert while taxiing for takeoff and note any bird- and mammal-activity reports by ATS providers and other operators.
- While taxiing, report wildlife activity observed on ramps, taxiways and runways to ATS providers, UNICOM and other aircraft.
- 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
In spite of the protection provided by a propeller, birds can still enter the intakes of turboprop engines, resulting in significant power loss.
While rolling onto the runway, prepare yourself mentally to deal with the consequences of a bird or mammal strike during takeoff. Be aware of conditions that may affect your ability to either reject takeoff or continue flying under reduced aircraft performance. These include:
- runway surface conditions,
- weather, and
- 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.
- Be aware that an aircraft taking off in front of you may frighten birds and mammals into your flight path.
- If there is bird activity on the runway, be prepared to wait for wildlifemanagement personnel to clear the birds. If traffic and weather conditions permit, use another runway. Wildlife hazards should be treated like any other flight safety hazard—if any doubt exists concerning safety, delay your takeoff until conditions are right.
- Use landing lights during takeoff. Although there is no conclusive evidence that birds see and avoid aircraft lights, limited data and anecdotal evidence suggest landing lights—particularly pulsed landing lights—make the aircraft more visible to birds and provide more time for the animals to take evasive action.
- 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.
- Select engine ignition on for takeoff to enhance engine flameout protection when operating turbine-powered aircraft in the presence of birds.
- Should a bird or mammal strike occur during takeoff roll, a rejected takeoff is the safest course of action when 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).
- Be prepared to adjust your climb route to avoid birds.
- If there is reported bird activity, plan to operate the aircraft at reduced airspeeds to minimize impact force and aircraft damage.
- If there is an altitude band where birds are anticipated, climb through these altitudes as quickly as possible, using the manufacturer’s recommended best rate of climb speed.
- The majority of bird strikes occur below 10,000 ft AGL, so continue to use landing lights during climb until above this altitude.
- Listen to appropriate enroute radio frequencies to obtain up-to-date information on bird activity from ATS providers and other aircraft.
- Report all hazardous bird movements to ATS providers and other aircraft.
Approach and landing
- 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).
- Obtain the latest bird and mammal activity information from ATS providers, ATIS, UNICOM and other aircraft.
- Be especially vigilant when operating at airports which 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.
- Plan your descent and approach route to avoid areas that attract birds.
- During descent and approach in areas with high bird activity, reduce airspeed to diminish the severity of potential bird strikes.
- If bird activity is reported at particular altitudes, use a higher rate of descent— without increasing speed—to minimize exposure to potential bird strikes.
- Wildlife hazards during approach and landing should be treated like any other flight safety hazard—if any doubt exists concerning safety, delay your landing until conditions are right.
- If birds are encountered on approach, 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 your 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.
- Use landing lights during approach and landing to make the aircraft more visible to birds.
- If you encounter birds or mammals, be sure to report this activity to ATS providers, UNICOM and other aircraft.
If you’ve struck a bird or mammal, or suspect a strike occurred:
- have the aircraft thoroughly inspected by an aircraft maintenance engineer (AME) prior to the next flight; and
- if necessary, report the incident to the Transportation Safety Board of Canada.
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 the bird- and wildlife-strike reporting process.) When completing bird- and mammal-strike reports consider:
- providing further useful information: photograph all bird remains and damage and send the photographs to Transport Canada along with the report.
- if unable to identify the struck species, collect all remains—no matter how small—and contact Transport Canada to arrange for assistance (see Appendix C for contact information).
Commercial and business aviation: special considerations
There are specific bird-hazard concerns for pilots in commercial and business aviation:
The structures and engines of larger commercial and business aircraft are more capable of withstanding bird-strike impacts; they are certified to more stringent bird-strike standards than those applying to light general-aviation aircraft (see Chapter 5). However, both the probability and severity of bird strikes is increased for commercial and business aircraft due to a number of factors:
- Operating speeds are higher, reducing the time available to observe wildlife activity and increasing potential impact force and damage should a bird strike occur.
- The physical size of these aircraft means more airframe is exposed; an encounter with a flock of birds might lead to damage at numerous locations on the aircraft.
- These aircraft are larger and less maneuverable, making evasive action difficult.
- Aircraft size, windshield size, and cockpit location restrict visibility, limiting the ability to see birds and mammals.
- The extreme workload during critical flight phases means the flight crew has limited time in which to observe wildlife activity.
- Requests for alternate runways to avoid bird concentrations at busy airports can lead to significant delays. Similarly, 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.
- In the 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.
- In the 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.
- Aircraft accident statistics show a high number of accidents during rejected takeoffs among business and commercial aircraft. The decision to reject a 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.
- 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—and the growth of the bird population, serious damage from an airborne encounter with a flock of waterfowl is a distinct possibility.
The following suggested operating techniques can assist in reducing the probability and severity of bird and mammal strikes involving commercial and business aircraft:
- Prior to engine start, review emergency procedures pertinent to your aircraft type and operation. Pay particular attention to rejected-takeoff and enginefailure procedures.
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 the airport boundary as possible, where bird activity is managed.
- The most effective way to reduce the severity of a bird strike is to reduce speed. Bird-impact force increases as the square of speed; doubling speed increases the impact force by a factor of four.
- 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 ft AGL occur less frequently, but the majority of these strikes involve larger birds that incur frequent and significant damage.
- Use landing lights at all times when operating the aircraft below 10,000 ft AGL.
General aviation: special considerations
Pilots in this sector should consider these points:
- The majority of general-aviation aircraft (piston single-engine aircraft) are certified under FAR 23. Airframe components in this class will withstand impacts only from the smallest of bird species (see Chapter 5).
- Many general-aviation pilots are infrequent flyers and therefore less experienced; they may lack familiarity and not be current in handling emergency procedures. Their knowledge of the latest information on bird activity in their local flying area—or on the planned flight route—may also be limited.
- Many general-aviation operations are from small, uncontrolled aerodromes lacking both wildlife management and available information on wildlife activity. These small aerodromes, however, may offer greater flexibility in the selection of alternate runways to avoid a wildlife hazard.
The following suggested operating techniques can help reduce the probability and severity of bird and mammal strikes to general-aviation aircraft.
- Reduce aircraft speed to diminish impact force when operating in areas of bird activity;
- For protection, be prepared to lower your head below the glareshield if a bird strike appears imminent;
- Fly at higher altitudes to reduce the probability of a bird strike. Only one percent of reported general-aviation bird strikes occur above 2,500 ft AGL; and
- Use landing lights during takeoff and landing to make the aircraft more visible to birds.
environments in which they
are highly vulnerable to
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Rotary-wing aviation: special considerations
Rotary-wing or helicopter operations are unique in aviation and deserve particular attention in bird-hazard matters:
Helicopters are constantly exposed to the risk of bird strikes 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 to the ground.
- Helicopter operating speeds are generallylower than fixed wing aircraft, but birdstrikecertification standards—even forTransport Category helicopters—are notstringent (see Chapter 5).
- Helicopters are more of a disturbance tobird colonies than fixed-wing airplanes;strike risk is therefore increased when birdsare flushed into the air.
- There is significant risk of birds penetratingthe windshield and causing serious injuryand incapacitation.
- The majority of helicopter flight operations are conducted at very low altitudes,typically below
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 helicopter pilots following windshieldpenetrations is loss of vision from flying debris.
- When possible, request bird-activity information daily.
- To reduce the probability of a bird strike, fly at higher altitudes between basesand operating areas.
- Ensure regular review of 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.
The following suggestions may be useful when siting helipads in remote areas:
- Helipads should not be located near waste disposal facilities such as food-wastelandfills, waste-transfer stations and compost facilities, which attract largeflocking birds such as gulls. Waste-disposal facilities also attract large mammalssuch as Black Bears and Grizzly Bears. These large predators are not only athreat to humans working around the helipad, they can also cause considerabledamage to equipment and helicopters in their search for food.
- Helipads should not be located near fish-packing and processing plants, orabattoirs. The waste from these facilities can attract large numbers of birds suchas gulls.
- Helipads should not be located near the flight paths of gulls flying betweendaytime feeding sites and nighttime roosting sites. During months when gullsroost on open water, regular and predictable flight paths are followed todaytime feeding sites. Many thousands of birds can follow these flight pathsover several hours. Normally, these flight paths are below 500 ft AGL, so greatcare must be taken when manoeuvring in this airspace—especially at sunriseand sunset.
- Helipads should not be located near migratory waterfowl refuges, or in thevicinity of sites such as grain fields. During spring and fall migration, manythousands of birds can fly in these areas.
- When helipads are located near agricultural fields and orchards, remember thatharvesting and plowing activities frequently attract large numbers of birds suchas crows and gulls. Conducting these activities at night minimizes the risk todaytime helicopter operations.
Flight training schools: special considerations
Flight training schools play an essential role in fostering understanding among pilots about wildlife hazards. As centres of learning, they not only assist pilots in honing the skills needed to avoid and manage strikes, but these schools also disseminate vital promotional and training materials to increase awareness of wildlife-strike risks.
With respect to wildlife hazards, flight training must accomplish the following:
- Emphasize the consequences of bird and mammal strikes by including statistical information on risks, and case studies from serious strike encounters involving different kinds of aircraft.
- Describe problem bird and mammal species and the situations in which students are most likely to encounter hazards during training.
- Describe the effects that single and multiple bird strikes may have on the performance of training aircraft.
- Emphasize how normal and emergency aircraft operating procedures address the likely effects of bird and mammal strikes on an aircraft.
- Emphasize adhering to emergency procedures in approved pilot’s operating handbooks or aircraft operating manuals in the event of any unusual situation, including bird or mammal strikes.
- Emphasize the importance of crew resource-management techniques to help pilots of large aircraft deal with unusual emergency scenarios that may follow a bird or mammal strike.
- Emphasize that a wildlife strike during takeoff affects aircraft performance; students should not reject takeoff after reaching V1 speed, unless the aircraft is unable to continue flight safely.
Train pilots in techniques that minimize the possibility of bird and mammal strikes, as well as actions that should be taken in the event of a strike:
- Ensure that flight planning is thorough, evaluating all aspects to reduce thepotential for wildlife strikes;
- Complete a thorough pre-flight inspection of the aircraft to ensure there are nonesting birds around the engine or in airframe cavities;
- During preflight preparation, obtain the latest wildlife-activity informationfrom ATS providers, UNICOM and other aircraft;
- While taxiing for takeoff, observe and report all wildlife activity;
- Delay takeoff if birds or mammals are reported or observed on the runway;
- Avoid flying at lower altitudes in areas of high bird activity;
- Reduce aircraft speed to diminish impact force;
- If you must fly through an area heavily populated by birds; minimize climb anddescent times; and
- Report all bird sightings deemed hazardous to ATS providers, UNICOM andother aircraft.
With critical responsibility for reducing the probability and severity of bird and mammal strikes, pilots have four important duties:
- To plan and operate all flights in ways that minimize the probability and severity of wildlife strikes.
- To stay on the lookout for birds and mammals.
- To report all wildlife activity to ATS providers, UNICOM and other aircraft.
- To file a Bird/Wildlife Strike Report with Transport Canada or other appropriate agencies following all wildlife strikes (see Appendix C for strike-reporting procedures).
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