Smithsonian Expert Fills in the Missing Science Behind the Movie “Sully”

Forensic ornithologist Carla Dove shares her story of analyzing the bird remains or “snarge” scraped from the engines of flight 1549

Flight 1549
After just moments in the air, flight 1549 collided with a flock of geese. USACE NY /Flickr CC

It’s a story many know: US Airways flight 1549 left LaGuardia airport on a chilly afternoon on January 15, 2009. Moments after lift off, a flock of Canada geese intercepted its path. The hefty birds were sucked into both engines, leaving 155 people hurtling along at 2,800 feet of altitude with no thrust. The plane was rapidly descending—with a rate comparable to an elevator dropping two floors per second. Captain Chesley “Sully” Sullenberger realized he couldn’t make it to an airport.

“This is the captain,” he said over the intercom. “Brace for impact.”

Just 208 seconds after the engines died, Sully and his co-pilot Jeff Skiles pulled off an extraordinary landing on the river. All 155 survived.

The recently released film Sully: The Untold Story of the Miracle on the Hudson dives into the events that occurred that day and explores the emotional distress and flashbacks the captain and Skiles suffered for weeks after the traumatic landing. The movie is centered around the ensuing National Transportation Safety Board (NTSB) investigation and the agency’s computer simulations, which were intended to determine whether the pilots made the correct decisions. But there is more to this tale. 

Just days after the crash, a team of scientists led by renowned forensic ornithologist Carla Dove at the Smithsonian’s National Museum of Natural History in Washington, D.C., began poring over the bird remains scraped from the plane’s engines. From this potent smelling mess of ground up bird parts, they hoped to tease out information that could help piece together what happened that day and how to prevent similar events in the future.

Recently, I invited Dove to go see the new film and the highly charged recounting of the events that day returned her to the moment she first learned of the tragedy.

“I was sitting in my office,” she says. “And my telephone started lighting up like a Christmas tree.” Jumbled information about what was going on flooded in.

“If this was a bird,” she remembers thinking. “This is something that is going to change the way we look at aviation safety.”

Sully - Official Trailer [HD]

Over her long career in Smithsonian’s ornithology department, she’s studied many cases of bird-plane collisions known as bird strikes. At the time, some were speculating that geese caused the emergency landing of flight 1549. The first time she worked a case involving a species of such a large bird was in 1995 when an AWACS plane crash landed outside of Anchorage, Alaska. All 24 people on that plane died, she says.

In the chaos ensuing after flight 1549’s water landing, information on survivors was not readily available. Dismayed, Dove turned off her computer and headed for her office door, thinking, “when I get home, all these people are going to be dead.”

Remarkably, that wasn’t the case.

The next day she received a call from colleagues at the USDA in New York who were collecting remains for her to study. Over the next several days Dove and her team teased through what was eventually some 69 samples of bird remains, appropriately she calls this “snarge.”

There were many questions the team hoped to answer during the course of their investigation: What species of bird was it? Was there more than one species? How far back into the engines did the bird remains go? How many birds were involved?

Though the samples included a few full bird feathers, most were incomprehensible sludge. The remains were minced into pieces, ground up with fuel and debris from the engine as well as mud and detritus from the river. So Dove and her team had to primarily rely on microscopic and DNA evidence for answers.

Scraping Snarge
Scientists from the USDA scrape the bird remains, called "snarge," off of one of the plane's engine. Courtesy of Carla Dove

Their analysis showed that the birds were all geese. Hydrogen isotope analysis also showed that the geese had migrated down from Canada to New York to overwinter in the comparatively balmy temperatures.

This analysis also fit with the altitude at which the birds struck the plane, Dove explains. It was the peak of winter, when most nearby ponds and lakes were frozen. When this happens, migratory geese, lean from their venture South, flock together to search for food, which would explain their altitude at the time, says Dove. “Your fat typical park goose isn’t going to get up on a cold January day and do that,” she says.

Unfortunately the DNA of the bird remains couldn’t give them estimates on the number of birds in the flock—mixed with river debris, the analysis didn’t provide clean results. DNA sexing showed it was at least two birds (one male one female), but Dove says it was likely a large flock.

Dove and her team are working towards making the air a safer place for birds and people alike. Their findings from the investigation after the events on January 15 have led to more research and new solutions to prevent bird strikes.

“That crash was really a wakeup call for the FAA to start paying attention to these habitat issues,” she says.

Flight 1549
Passengers gather on the wings of Flight 1549 waiting for rescue boats. Greg Lam Pak Ng/Flickr CC

Most commercial airplane engines are certified to withstand the impact of a single four-pound bird (an average Canada goose can weigh anywhere from 7 to nearly 20 pounds) on the airframe, windshields and engines. And the numbers of these large birds are on the rise. “There is more meat in the air now than there was 30 years ago,” she says.

Though the smaller songbird species have declined in recent years, one study suggests that 13 of the 14 largest bird species in North America (weighing over eight pounds) have increased over the last 40 years. Paralleling this increase in large birds is a greater amount of air traffic and bird strikes.

The problem is a pricey and dangerous one. Wildlife strikes can cost more than $500 million in damage each year. From 1990 to 2016 these strikes have also resulted in 400 human injuries and 26 fatalities, according to the Bird Strike Committee USA.

Currently, one of the most important mitigation measures are wildlife airport assessments, explains Dove. In these assessments biologists examine the airfield to determine what can be done to keep birds away—from the positioning of ponds to grass height. Airports will often employ other deterrents like pyrotechnics or even other birds.

Research into bird strikes has shifted focus towards making planes more visible to birds and tracking their migratory patterns using radar. One such radar system was installed in the Seattle-Tacoma International Airport. The system is intended to understand the patterns and paths of the local avians’ movements, but researchers are still working to use the system to provide real-time information to pilots and ground control.

Though the strikes make up a small percentage of total airline travel, there is still more that could be done to continue to reduce them. And though the double engine loss of Flight 1549 is rare, a repeat occurrence is a horrifying thought. The last words Sully and Skiles exchanged before the plane hit the water captured the helplessness of their situation.

“Got any ideas?” Sully asked. Skiles replied, “actually, no."

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