The risk of commercial airplanes crashing because they have struck large birds is increasing and design standards should be strengthened so that aircraft can withstand the collisions, U.S. government safety officials said Tuesday.
The National Transportation Safety Board voted to recommend the Federal Aviation Administration revise its current standards, which require airframes be able to withstand a collision with a 4-pound (2-kilogram)bird and that airplane tails be able to withstand an 8-pound (4-kilogram) bird. The recommendation did not include engines.
The airframe standards were established in the 1970s, but thanks to environment protections populations of most large bird species in North American have been increasing. Many of the species of greatest concern have average weights double or triple the current standards.
Air traffic also has increased dramatically, with annual takeoffs and landings in the United States are forecast to surpass 1 billion a year by 2020. That means more planes and more large birds sharing the skies.
The board made its recommendation after determining the cause of a business jet crash in Oklahoma last year that killed five men was a collision with a flock of white pelicans, a species that can weigh as much as 30 pounds (14 kilograms). Investigators said that striking the pelicans severely damaged a wing of the Cessna Citation 500 and knocked out the power in one engine. They said the plane could have continued to fly using its other engine, but not with the wing damage.
The collision took place about two minutes after takeoff from Wiley Post Airport on March 4, 2008, as the plane passed over Oklahoma City's Lake Overholser. Witnesses told investigators they heard a noise that sounded like an engine stall, and then saw a plane plunge nose down trailing a plume of gray smoke.
Killed were pilots Tim Hartman, 44, and Rick Sandoval, 40, and three executives: Garth Bates Jr., 59, Frank Pool Jr., 60, and Lloyd Austin, 57.
The danger of bird-aircraft collisions has received extensive scrutiny since US Airways Flight 1549 ditched into the Hudson River in January after striking a flock of Canada geese following takeoff from New York's LaGuardia Airport. The incident was dubbed the "Miracle on the Hudson" when all 155 people aboard survived.
In both cases the collisions took place shortly after takeoff roughly four miles (7 kilometers) from the airport at an altitude of about 3,000 feet (900 meters). Both planes struck flocks of large, migratory birds.
A panel that included FAA, safety agencies from other countries and the aviation industry spent 10 years studying whether airframes need to be strengthened to withstand larger birds, but disbanded without taking action.
"I think that's ridiculous," NTSB chairman Debbie Hersman said. "That's a tremendous waste of time and expertise." She said FAA needs to "be publishing rules and getting on with what's feasible."
FAA spokeswoman Diane Spitaliere said the agency will consider the board's recommendation and take action if warranted. She said one reason standards haven't been changed is a concern that doing so will increase the weight of planes.
The safety board also reiterated a recommendation it made in 1999 that airports and airlines be required to report bird strikes to a database maintained by the FAA and the Agriculture Department. The government has been collecting data on bird and other wildlife collisions since 1990, but the agency has kept reporting voluntary. There have been 89,000 incidents reported to the database since it was created in 1990, but they represent only an estimated 20 percent of collisions.
Since 1988, 53 people have been killed and 81 commercial aircraft destroyed in bird or other wildlife collisions in the United States, said Richard Dolbeer, a leading expert on bird strikes. Dolbeer said his data probably is incomplete because it is based in part on news reports and because the causes of some crashes have not been determined.
Investigators said mandatory reporting would make it easier to see where the problem is greatest and where countermeasures have been most effective.
FAA officials were criticized at a recent U.S. Senate hearing for failing to implement dozens of NTSB recommendations like the mandatory reporting requirement.
The board also reiterated a recommendation it made in 1999 that airports and airlines be required to report bird strikes to a database maintained by FAA and the Agriculture Department. The government has been collecting data on bird and other wildlife collisions since 1990, but FAA has kept reporting voluntary. Only about 20 percent of collisions are currently reported to the database.
Investigators said mandatory reporting would make it easier to see where the problem is greatest and where countermeasures have been most effective.
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