Moments after United Flight 1738 took off from O’Hare International Airport on the clear morning of Thursday, June 1, passenger Drew Tewksbury heard a thud. The plane tilted left, then leveled out.
Tewksbury, 48, an insurance executive from Chagrin Falls, Ohio, said the plane’s right engine started making the sound of a car driving down a highway with a flat tire.
“Within 30 seconds, someone in the back said, ‘Hey, there’s flames coming out’,” he said.
Bound for Miami, the twin-engine Boeing 737-900 suffered a bird strike. According to air traffic control recordings, pilots said the plane struck a flock of geese.
Video posted on Twitter shows flames spitting from the No. 2 engine.
— Tim (@tim_ea_arnold) June 1, 2017
Flight 1738 circled over Lake Michigan before turning back toward O’Hare, making an emergency landing at about 8:30 a.m., according to Flightstats.com. With one engine, the plane couldn’t use its reverse thrust to slow down, making for a rough landing, said Tewksbury.
“It was only brakes,” said Tewksbury, who connected at O’Hare from Cleveland for a work trip. “The pilots did a great job.”
Passengers boarded another plane for Miami later that morning.
Aircraft bird strikes are a reality of modern aviation, but they usually aren’t a problem.
“Sometimes we don’t even know that we had a bird strike,” said Joseph McElwee, 29, a pilot for a major U.S.-based airline.
Planes hit thousands of birds each year in the U.S., according to the Federal Aviation Authority’s Wildlife Strike Database, which began tracking in 1990. When strikes happen, damage ranges from repairable fender-benders like dented noses and cracked windshields to critical, costly engine failures.
Many Americans are familiar with the “Miracle on the Hudson” in 2009, when both engines of US Airways Flight 1549 ingested geese, causing the Airbus A320 to lose power and land in the Hudson River between New Jersey and Manhattan.
From 1990 to April 2016, the most recent data, Chicago’s O’Hare and Midway airports reported a combined 5,387 strikes, with more than 4,000 from O’Hare alone (about 75 percent). But reports have climbed since 2001 when the FAA made electronic reporting available. During the same period, there were 166,276 total strikes reported in the U.S.
At both Chicago airports, about two-thirds of strikes occur during the day. About 50 percent happen during approach.
The American kestrel, a small variety of falcon, shares the morbid distinction as the most-struck bird at both O’Hare and Midway. Nationally, it ranks second to the Mourning dove. Both airports report Killdeer, Mourning doves, and red-tailed hawks, as well.
“Raptors (hawk & kestrel) like hunting small rodents in the short grass,” said Carl Giometti, president of the Chicago Ornithological Society, via email. “Airports provide great perches where they can scan over a large area.”
Canada geese don’t rank in the top 10 for either airport, but they tend to make headlines because their larger mass can cripple an aircraft.
The FAA estimates economic losses from bird strikes at $666 million since 1990. It attributes 20 percent, about $127 million, to Canada geese. Planes coming and going from Chicago’s airports hit 139 species of birds, as well as 16 species of non-birds typically considered as roadkill, including raccoons, bats, deer, rabbits, turtles, coyotes, foxes, and skunks.
Identifying species isn’t always easy, especially when only feathers or blood remain.
That’s when airlines turn to the Smithsonian Institution’s Feather Identification Lab. Based in Washington, D.C., the lab analyzes remnant samples that airports send in the form of feathers, fragments, bills, talons, tissue, and feet. “Anything that they find,” said Dr. Carla Dove, a forensic ornithologist who directs the lab.
There’s even a term for a bird’s gooey remains after a plane strike: snarge.
The lab gets over 8,000 cases a year, including ones from the Air Force and Navy, according to Marcy Heacker, research assistant at the Smithsonian Institution. The FAA doesn’t require the commercial airline industry to report strikes, but the agency encourages it.
“Thank goodness we do not see rare species very often,” Heacker said.
She said cases usually peak in October when birds migrate. Data for Midway and O’Hare show strikes peak in late summer.
Lt. Andrew Horvath, 31, a Navy pilot based in Norfolk, Virginia, said he’s had about a dozen bird strikes in almost a decade of flying. “I’ve seen carrion birds soaring solo up to 6,000 feet, flocks of egrets at 4,000 feet, seagulls the size of watermelons at 3,000 feet, and finches soaring just inches above terra firma.”
There is positive news. As more reports are submitted each year, there’s been a decline in the rate of damage-causing strikes nationally. FAA data shows from 2000 to 2015, the number and rate (per 100,000 aircraft movements) of damaging strikes dropped 32 and 19 percent, respectively.
Notes on the reporting:
I obtained my data from FAA Wildlife Strike Database: https://wildlife.faa.gov/database.aspx
From there, I compiled all available data for ORD and MDW. Pivot tables are labeled on separate sheets: https://docs.google.com/a/u.northwestern.edu/spreadsheets/d/19hp5A-6EdCTGxyHhWihrxeMyQp0m55IqzOpS7Krg8aE/edit?usp=sharing
Combining O’Hare and Midway data seemed like the best way to show Chicago’s overall data, since they are two of the busiest airports in the country.
Pivot tables include: damage counts, incident counts by year, phase of flight when strikes occur, time of day, and percent change of reports by year since 2000.