Special to ABCNEWS.com
An AWACS Air Force surveillance plane had just lifted off from Elmendorf Air Force Base near Anchorage, Alaska, when something went
very wrong.
Eyewitnesses watched as the plane crashed in an enormous
fireball just two miles from the end of the runway. The crash ignited
125,000 pounds of jet fuel, sending up a cloud of black smoke that could be
seen 30 miles away.
All 24 crewmen died that morning of Sept. 23, 1995.
At the end of the runway, Air Force investigators found about a dozen dead Canada geese. Migration season was beginning for the birds, each of which can weigh 13 pounds and have a wingspan nearing 4 feet.
It wasn’t the first time an aircraft has been brought down by birds,
although crashes are rare.
Ed Cleary, wildlife biologist for the
Federal Aviation Administration, says civil pilots reported 16,283 collisions
with birds from 1990 through 1998, but he added that since reporting is
voluntary, the real number is probably five times higher.
The collisions resulted in 1,268 aircraft with “substantial” damage, and 19 planes were destroyed. There were no reported fatalities. These numbers, however, don’t include military encounters.
The Price of Flight
In the past eight years, the reported damages have added up to about $48 million.
As summer ends in the northern hemisphere, Swainson’s hawks leave their nests and head south. While migrating, they travel in groups of as many as 100 — a potential hazard for pilots. (USFS)
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Birds can jam jet turbines and smash through the windshields of small planes,
making birds an equal opportunity threat to all levels of aviation.
Scientists are trying everything from high-tech tricks to simply understanding better bird habits. There isn’t a one-size-fits-all solution, but we’ve come a
long way from the early 1950s, when authorities seriously considered using
powerful radar to “burn” birds out of the air near airports.
George Young, associate professor of meteorology and geoenvironmental
engineering at Penn State University, came to the problem with a rare set of qualifications.
He’s a birder, a weatherman and a soaring
enthusiast who has done weather forecasting for glider competitions. Young
reasoned that soaring birds — as opposed to flapping birds —
present an unusual challenge because they can reach heights where pilots might not expect any feathered company.
Riding High
As a gliding enthusiast, Young also knew that soaring birds are subject to
the same kind of limitations as glider pilots. Both rely on rising columns
of warm air called thermals, which occur in the lower atmosphere and
are produced by variations in ground temperatures.
Working with the Center for Conservation Research and Technology in
Baltimore, Young focused on three birds: white pelicans, Swainson’s hawks and turkey vultures. Using satellites, he tracked the birds.
“Some days the birds soared two miles high and other days they went no more than 100 feet above the ground,” he says. The superachiever was the
American white pelican that reached as high as 14,000 feet in just 10
minutes on some days but stayed much lower on others.
The difference, he says, was the thermals.
And therein, he says, lies part of the solution. Weather forecasters
may not always know when it’s raining, but they’re much better at predicting high and low temperatures.
Thermal Forecasts
It should then be possible to predict the presence of thermals at least a
full day ahead, thus warning pilots near airports of the likelihood of
soaring birds.
He’s working on a system that would help local airports monitor
conditions and predict at what altitude birds are most likely to be at
any given time. That should make it easier for pilots to avoid them.
Yet not all birds soar.
Most make mileage by flapping their wings, and
Young has embarked on a years-long study of geese, swans and ducks to see
if he can come up with some sort of warning system for them as well.
About 90 percent of collisions occur at relatively low altitudes,
less than 3,000 feet above the ground, but strikes are common at higher
altitudes during seasonal migrations, according to FAA statistics.
The most common hits are gulls, which tend to fly in dense flocks,
followed by waterfowl, vultures, hawks, owls, egrets, blackbirds and
starlings.
Fowl Airports
For some odd reason, birds seem to love airports, and that has prompted
some officials to take innovative measures.
The Southwest Florida International Airport in Fort Myers has trained a
2-year-old border collie to chase birds away from the airport. The
birds learned to ignore other techniques, such as pyrotechnics and loud
noises, but when Jet the dog speaks, they flap away.
After the crash of the Air Force surveillance plane in 1995, the Air Mobility
Command set out to reduce the 600 or so bird collisions reported by Air
Force pilots in a typical year.
The command ordered bases to consider these tactics:
 Broadcasting bird distress calls to see if they can convince the birds to go elsewhere.
Bringing in trained hawks to intimidate smaller birds.
Banning takeoffs when the bird hazard is great.
Stopping lawn mowing. If the grass around the airport is 7 to 14 inches high, it makes it
harder for birds to peck for food.
Yucky Food
If that doesn’t work, says Will Summers, the command’s natural resources manager, set out a
little bird food with purgatives to make the birds sick enough to move on
to a better food supply.
He also advises against planting different types of ground covers, which
could attract different types of birds. If there’s a lot there to eat, he
says, the birds will think they’ve found a fast-food joint.
Other Air Force officials are taking a more high-tech approach.
Researchers at the Wright Laboratory in Dayton, Ohio, note that birds, like
humans, can hear radar if it is at a very low frequency with
occasional frequency spikes. They are developing a plan to put radar
on airplanes that could “broadcast” their approach to an airport, thereby
warning birds to get out of the way.
It’s sort of an “audible headlight for the aircraft,” as one researcher
put it.
It would brighten the skies for both birds and pilots.
Lee Dye’s column appears Wednesdays on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.
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S U M M A R Y
Making the skies safer for birds and planes alike may just require different weather forecasts.
The most common collisions are with gulls, which tend to fly in dense flocks, followed by waterfowl, vultures, hawks, owls, egrets, blackbirds and starlings.
E - M A I L U S
Write Lee Dye
 A R C H I V E
Lee Dye’s past columns
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Center for Conservation Research & Technology
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