The Top 10
Bird Strike Myths
There are many misconceptions by air travelers and the general public
about the threat posed by birds to aircraft and their occupants. The
following facts should shed some light on some of these issues.
- Myth - Bird strikes cannot cause serious airline accidents.
Fact - Since 1975,
nine large jet airliners have had major accidents where bird strikes
played a significant role. In one case, about three dozen people were
- Myth - Bird strikes are rare.
Fact – Over 87,000 bird strikes to civil aircraft in the United
States were reported to the Federal Aviation Administration (FAA) from
1990-2008, a mere 20% of the number that likely occurred.
- Myth - Bird strikes are no more of a problem today than 20 or 30 years
Fact - In North America, bird strike
hazards are increasing. Because of outstanding wildlife conservation and
environmental programs in North America,
populations of many bird species have increased dramatically since the
1970s. Millions of acres have been set aside as wildlife refuges and
strong environmental laws such as the Migratory Bird Treaty Act and the
Federal Insecticide, Fungicide and Rodenticide
Act have protected birds and other wildlife. As a result, species like
non-migratory Canada Geese, which frequent urban areas such as golf
courses, parks, and airports, have more than quadrupled in number from
1985 to 2008. As another example, the double-crested cormorant population
on the Great Lakes has increased over 1,000-fold,
from 89 nesting pairs in 1972 to over 100,000 pairs in 2009. These
increases have led to an increase in the number of birds in the vicinity
of both large and small airports and greater opportunities for birds,
especially larger birds, to be hit by aircraft.
- Myth - Large aircraft are built to withstand all bird strikes.
Fact - Large
commercial aircraft like passenger jets are certified to be able to
continue flying after impacting a 4-lb bird, even if substantial and
costly damage occurs and even if one engine has to be shut down. However, 36 species of birds in North
America weigh over 4 lbs and most of these large birds
travel in flocks. About 30% of
reported strikes by birds weighing more than 4 lbs to civil aircraft in USA,
1990-2008, involved multiple birds.
Even flocks of small birds (e.g., starlings, blackbirds) and
single medium sized birds (e.g., gulls, ducks, hawks) can cause engine
failure and substantial damage.
- Myth - If a bird flies into an engine during takeoff and the engine
quits, the airplane will crash.
Fact - Large commercial jets are designed so that if any 1 engine
is unable to continue generating thrust, the airplane will have enough
power from the remaining engine or engines to safely complete the
flight. However, because many
birds travel in flocks, there is always a possibility that birds will be
ingested into multiple engines.
- Myth - Nothing can be done to keep birds away from airports.
Fact - There are a
number of effective techniques that can reduce the number of birds in
the airport area. In general, the techniques fall into three categories:
making the environment unattractive for birds, scaring the birds, or as
a last resort, reducing the bird population.
- Myth - It is illegal to kill birds just to protect aircraft.
Fact - In North
America, there are a few introduced (non-native) birds such
as pigeons and starlings which are not federally protected species and
generally may be killed without special permits if they pose a threat to
aircraft. Most birds, such as ducks, geese, gulls, and herons, may be
killed in limited number by an airport authority only after obtaining
appropriate permits and demonstrating that non-lethal techniques are not
adequate. Endangered species may not be killed under any circumstances.
- Myth - If birds are a problem at an airport, killing them all would
eliminate the problem.
Fact - Even if it
were legal to do so, killing off all birds at an airport will not solve
the problem. An airport is an integral part of the local ecosystem, and like in all ecosystems, each plant or
animal species plays an important role. Eliminating any one problem
species will only lead to some other species taking its place. A
combination of bird control measures which take into account habitat
management to reduce the attractions of food, water and shelter is a
superior long-term solution.
- Myth - Except for the very rare accident, bird strikes are only a
nuisance to airline operators.
Fact - For a modern jet
airliner, even minor damage can lead to significant costs. For example,
if a bird strike results in damage that leads to replacing a single pair
of fan blades, the airline has to deal with not only the direct cost of
labor and materials, but also the indirect costs of keeping the aircraft
out of revenue service and redirecting passengers. The FAA estimates
that bird strikes cost civil aviation over $600 million per year in the USA,
1990-2008. Worldwide, bird strikes cost commercial air carriers over $1.2
billion each year. Furthermore, minor damage to airliners is usually not
covered by aircraft hull or engine insurance, so the costs of most bird
strikes directly affect airline profits.
- Myth - Bird strikes are a concern only to those who fly.
Fact - The issue of
bird strikes is tied into a wide range of social and policy issues that
go beyond aviation. One important area where this is true is the
environment. Past and present policies of wildlife and habitat
management can directly affect bird populations and bird strike hazards.
Certain uses of land (e.g., landfills, wildlife refuges) within 5 miles
of airports may need to be restricted or prohibited because these uses
attract hazardous wildlife.
Because bird strikes can lead to aircraft accidents, bird strikes
can have a direct effect on both the families and friends of potential
victims both in the aircraft and on the ground. Bird strikes can also
have environmental consequences. For example, as a result of a bird
strike that disabled an engine on a B-747 departing Los
Angeles International Airport
(LAX) in August 2000, the pilot had to dump 83 tons of fuel over the Pacific
Ocean before returning to land safely at LAX.
- Bonus Myth – Bird strikes never occur at high
Fact – It is true that most strikes occur in the airport
environment. About 41% of
reported strikes with civil aircraft in USA
occur while the aircraft is on the ground during take-off or landing and
about 75% of strikes occur at less than 500 feet above ground level (AGL). However, over 2,200 strikes
involving civil aircraft at heights above 5,000 feet AGL
were reported from 1990-2008 in the USA. The world height record for a bird
strike is 37,000 feet (Griffon vulture off the coast of Africa).