Aviation Insurance Industry Concerns Grow with Bird Population

When we first learn to fly we are taught that among other things that our attention should be focused on traffic, weather and terrain.  In order to avoid significant damage to your aircraft, it is important to remember that the birds were in the sky before we were and it is critical to keep a close eye on them at all times.  As a matter of fact birds in the flight path of an aircraft go from cute to critical in a heartbeat of a humming bird.  For instance a Brown Pelican can weigh up to six pounds, a Dalmatian Pelican can weigh up to 33 pounds and a Turkey Buzzard 10 pounds.  Truly size does not matter in a potential collision with any bird since the tiny starling can have a body weight that is 27% more dense than certain gulls. The potential damage to your aircraft from the collision with a two bound bird at 105 knots creates an impact force of 4800 pounds.

 

So if these critters still seem cute, please consider the following facts from the Bird Strike Committee USA:

 

  • Over 219 people have been killed world-wide as a result of bird strikes since 1988.

 

  • Bird and other wildlife strikes cost USA civil aviation over $620 million/year, 1990-2007.

 

  • Over 5,000 bird strikes were reported by the U.S. Air Force in 2007.

 

  • Over 7,600 bird and other wildlife strikes were reported for USA civil aircraft in 2007.

 

  • Studies indicate only about 20% of bird strikes to civil aircraft at Part 139-certificated (passenger service) airports in USA are reported. Less than 5% of bird strikes at General Aviation airports are reported.

 

  • From 1990-2004, US airlines reported 31 incidents in which pilots had to dump fuel during a precautionary or emergency landing after striking birds on takeoff or climb out. An average of 11,600 gallons of jet fuel was released in each of these dumps.

 

  • Waterfowl (31%), gulls (26%), and raptors (18%) represented 75% of the reported bird strikes causing damage to USA civil aircraft, 1990-2007.

 

  • In 1890, about 60 European Starlings were released in Central Park, New York City. Starlings are now the second most abundant bird in North America with a late-summer population of over 150 million birds. Starlings are "feathered bullets", having a body density 27% higher than Herring gulls.

 

  • The North American non-migratory Canadian Goose population increased 3.6 fold from 1 million birds in 1990 to over 3.5 million in 2007. Over 1,400 Canadian Geese strikes with civil aircraft have been reported in the USA from 1990 to 2007. Over 40% of these strike events involved multiple birds.

 

  • A 12-lb Canadian Goose struck by a150-mph aircraft at lift-off generates the force of a 1,000-lb weight dropped from a height of 10 feet

 

  • The North American population of Greater Snow Geese increased from about 50,000 birds in 1966 to over 1,000,000 birds in 2007.

 

  • The nesting population of Bald Eagles in the contiguous USA increased from fewer than 400 pairs in 1970 (2 years before DDT and similar chlorinated-hydrocarbon insecticides were banned) to over 11,000 pairs in 2007. Over 100 Bald Eagle strikes with civil aircraft have been reported in USA, 1990-2007. Mean body mass of Bald Eagles = 9.1 lbs (male); 11.8 lbs (female).

 

  • The Great Lakes Cormorant population increased from only about 200 nesting adults in 1970 to over 260,000 nesting adults in 2006, a 1,000+-fold increase.

 

  • The North American White and Brown Pelican populations grew at average annual rates of 2.3% and 1.9%, respectively, 1966-2007.

 

  • At least 15,000 gulls were counted nesting on roofs in USA cities on the Great Lakes during a survey in 1994.

 
We find that there are many myths about bird strikes. Although it is true that most strikes occur in the airport environment, about 41% of reported strikes with civil aircraft in the 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 1,300 strikes involving civil aircraft at heights above 5,000 feet AGL were reported from 1990-2003.  The world height record for a strike is 37,000 feet.

 

So no matter you altitude or location it is possible to share the same exact airspace with one of our feathered friends.  This is one meeting you certainly would like to miss.  The following suggestions will assist you in doing this;

 

Avoidance

The U.S. Air Force Bird Aircraft Strike Team developed a website to predict bird habitats and movement.  The interactive tool on the Web site www.usahas.com/BAM allows aircraft operators to estimate the severity of bird strike potential for regions of the country during a two week period. The first year the Air Force used this information during preflight it saw a 70% reduction in bird strikes.

 

Situational Awareness

As a pilot in command the best defense against a birdstrike is your situational awareness in flight planning and execution.  It is a must that a pilot be mentally prepared for this possible emergency should it happen.  Also reviewing your flight path to avoid flight over wildlife refuges could save you a lot of grief from not only the bird but also from the people who protect them.  Statistics show that 90% of the bird strikes in the U.S. are by species federally protected under the Migratory Bird Act.


Energy Dissipation

The Bird Avoidance Model website recommends climbing above 3000 feet AGL as rapidly as possible when operating near flocks of birds.  Most strikes occur below that level.  Further pilots should slow their aircraft when they are confronted with birds.  It has been found that the speed of the aircraft is more important that the size of the bird when it comes to reducing the amount of energy transferred to the aircraft.

 

What should you do if you have a birdstrike on take off?  It is suggested that you abort the takeoff if you have enough runway left.  Then taxi off, shut down inspect the prop, intake, engine, under carriage, antennas, and brake lines.  If the damage is done after takeoff or in flight, continue to fly the aircraft and do not get distracted.  Follow appropriate emergency procedures and get the aircraft on the ground.  Then call your mechanic and your insurance agent to report the damage and then report the strike to the FAA.