How and Why Do Flocks of Birds Collide with Airplanes?

For those afraid of flying, midair turbulence or cabin panels blowing off an airliner might be among the more terrifying scenarios they imagine. But did you know that colliding with a flock of birds is also a major aviation hazard?

In April, 39 flamingos were killed when they collided with an Emirates passenger jet shortly before it touched down in Mumbai on India’s west coast. Exactly one year earlier, activists had warned against the construction of a second major airport for Mumbai, Navi Mumbai International Airport, set to be completed in 2032, due to its proximity to two bird sanctuaries and feeding grounds for several species of migratory birds, including flamingos.

Wildlife activity can be higher near coastal airports compared to inland ones, increasing the risk of bird-plane collisions. These incidents, known as bird strikes, are common.

How did the Emirates plane hit the flock of flamingos?

The Emirates Boeing 777 aircraft hit a flock of flamingos about 300 meters (1,000 feet) above the ground on May 20. Later that same night, a group of children in Ghatkopar, a suburb of Mumbai, reported finding flamingo carcasses on the road.

While 29 dead flamingos were found that night, another 10 were discovered the next morning, according to a report in the Indian Express newspaper, which quoted a forest official.

The airline confirmed the incident two days later.

"The aircraft landed safely, and all passengers and crew disembarked without injury. However, sadly, a number of flamingos were lost, and Emirates is cooperating with the authorities on the matter," a spokesperson told the Reuters news agency.

The aircraft was damaged, and the return flight, which had been scheduled to depart for Dubai the same day, was canceled, the spokesperson added.

What is the risk of birds colliding with aircraft?

More than 14,000 bird strikes are reported each year in the United States alone, according to the Federal Aviation Administration. In 2022, the United Kingdom’s Civil Aviation Authority reported nearly 1,500 bird strikes over the year.

A study conducted in 2020 by German researchers at the Delft University of Technology and the Netherlands Institute of Flight Guidance at the German Aerospace Center examined the rate of bird strikes per aircraft movements in several countries around the world. It found that Australia had the highest bird strike rate, nearly eight for every 10,000 aircraft movements, while the US had the lowest at 2.83.

Bird strikes rarely occur at higher altitudes. Collisions tend to happen when planes are in the same space where birds usually fly, such as when aircraft are approaching, landing at, or departing from airports.

Waterfowl, gulls, and raptors are the most common types of birds to come into contact with planes in the air, according to reports collected by the Bird Strike Committee based in the US.

What causes bird strikes?

Several factors put birds at risk of colliding with airplanes.

Birds are naturally attracted to habitats often located around airports, such as open fields, wetlands, and bodies of water that serve as feeding and nesting grounds.

For instance, flamingos commonly live in large, shallow lakes and lagoons that can be close to land selected for the construction of coastal airports.

Although inland airports have less bird activity, even water pooling on uneven pavements can attract them.

Many birds are migratory. As a result, their flight paths can intersect with air traffic routes, especially during migration seasons when they make long journeys between breeding and feeding grounds.

Birds often fly in flocks, increasing the likelihood of multiple fatalities in the event of a collision.

Have people been injured or killed in bird strikes?

A particularly deadly incident occurred in October 1960 when Eastern Airlines Flight 375, a Lockheed Electra plane, was hit by birds. Just 20 seconds after takeoff from Boston Logan International Airport, a large flock of European starlings struck the plane’s engines. The aircraft lost power and crashed into Boston Harbor, killing all but 10 of the 72 people on board.

In 1988, 35 of the 104 people on board an Ethiopian Airlines Boeing 737 aircraft were killed when it crashed after several birds flew into its engines during takeoff from Bahir Dar, Ethiopia.

Over the past 31 years, bird strikes have caused the deaths of 292 people around the world.

Injuries can occur as well. In 2009, US Airways Flight 1549 made an emergency landing in the Hudson River after hitting a flock of Canadian geese shortly after takeoff. The plane’s engines sucked in the geese after impact and lost power. Although 100 people on board were injured, all 155 passengers and crew were rescued by boats. The incident later became the subject of a Hollywood film, "Miracle on the Hudson," starring Tom Hanks.

A decade later, in 2019, a Russian passenger plane struck a flock of gulls and had to make an emergency landing in a cornfield near Moscow. The event became known as the “Miracle over Ramensk.” Seventy-four of the 233 passengers on board suffered minor injuries.

Can bird strikes damage planes?

In most collisions, birds hit the windscreen of an aircraft or fly into engines, which can sometimes result in an emergency landing or, in rare cases, a crash.

Even a strike that has not caused obvious damage can reduce engine power and add to operating costs.

From 2013 to 2018, bird strikes caused $340 million in damage to aircraft, according to an analysis by the Allianz Global Corporate and Specialty insurance company.

The firm reported that insurers received more than 900 bird-strike-related claims during those five years to cover the costs of repairing damaged engines and airframes, which include mechanical structures such as wings. The average claim was for $368,000, while some were in excess of $16 million.

Can bird-plane collisions be prevented?

Since many bird strikes occur near airports, airport authorities and managers can reduce the risk of collisions through bird management and control. This involves first using a radar system to detect their presence.

In addition to using better detection systems to alert pilots to adjust their flight paths, several techniques can be employed to scare away birds. Bird distress signals, decoy animals, or using sounds and lights are some of the ways in which birds can be directed away from planes close to an airport.

Additionally, conservationists advocate for the creation of safe migratory corridors for birds. These are networks of connected habitats created after identifying common migratory routes. They provide access to necessary resources such as food, water, and resting areas, and help maintain biodiversity.

In some cases, these wildlife corridors are naturally existing, protected areas. In others, habitats fragmented by human activity can be reconnected.