Since January 2007, at least 26 serious birdstrikes were reported. In some of them, the aircraft's brakes caught fire or cabins and cockpits filled with smoke and the stench of burning birds. Engines failed and fan blades broke. In one case, a birdstrike left a 12-inch hole in the wing of a Boeing 757-200.
The NASA data does not include details such as the names of crews, airlines, and in many cases, the airports involved
- confidentiality designed to encourage greater reporting.
"That's only touching the tip of the iceberg," said former National Transportation Safety Board member John Goglia. "Clearly, we don't have knowledge of the full width and breadth of this problem."
From 1990 to 2007, there were nearly 80,000 reported incidents of birds striking nonmilitary aircraft, about one strike for every 10,000 flights, according to the Federal Aviation Administration and the Agriculture Department. But those numbers also are based on voluntary reports, which aviation safety experts say almost certainly underestimates the size of the problem and fails to convey the severity of some incidents.
In some cases reported to the NASA database, crews said they could smell birds burning in the engines
- "a toxic smell like burning toast (or) popcorn" wrote a flight attendant on an MD-80 airliner that had just taken off last March. After returning to the airport for an emergency landing, it was discovered the aircraft had suffered a birdstrike on a previous landing that had gone undetected.
The pilot of a Boeing 767-200 reported aborting a takeoff after the cockpit "filled with the smell of cooking bird." The plane had "ingested" birds in the right engine on a prior landing, but mechanics had thought the birds had passed through the engine and had given the flight the go-ahead to takeoff again.
Among other cases detailed in the NASA database:
-In March 2007, the pilot of a Boeing 777-200, a wide-bodied airliner that typically seats over 280 passengers, reported a birdstrike in the right engine shortly after a takeoff, causing strong engine vibrations. The pilot shut down the engine and asked to divert to another airport for an emergency landing, dumping as much of the plane's 160,000 pounds of fuel as possible to reduce the plane's landing weight and cut its risk of breaking apart.
-In June 2007, a Boeing 757-200 at Denver International Airport was forced to abort a takeoff at between 150 mph and 160 mph after a flock of birds the size of grapefruit flew into the path of the plane. Some birds were sucked into both engines, the pilot reported.
-In July 2008, the pilot of a Boeing 737-300 in the midst of a 139-mph takeoff roll spotted a hawk with a 4-foot wing span on the runway. As the bird flew past the left side of the plane, the crew heard a "very loud bang" and there was engine surge. The pilot aborted the takeoff at great strain to the aircraft's brakes, which caught fire. Fire trucks doused the flames. No one was hurt.