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Late Monday evening, Virgin Australia flight VA 148 took off from Queenstown in New Zealand, bound for Melbourne. Shortly after takeoff, the right engine of the Boeing 737-800 emitted loud bangs, followed by flames.
The pilot continued flying with the remaining engine and brought the aircraft’s 73 passengers and crew to a safe emergency landing at nearby Invercargill Airport.
According to Virgin Australia, the dramatic turn of events was caused by a “possible bird strike”. Queenstown Airport downplayed the likelihood of a bird strike, stating “no birds were sighted at the airfield at this time”.
Although we don’t know exactly what happened, bird strikes are a common and real risk to aircraft. They can damage aircraft and even cause death.
A bird strike is a collision between an aircraft and a bird. (The definition is sometimes expanded to include ground collisions with land animals such as deer, rabbits, dogs, and alligators.)
The first bird strike was recorded in 1905 by Orville Wright over a cornfield in Ohio.
Today they occur daily, although there are some seasonal variations due to the birds’ migration patterns.
Perhaps the most famous collision with a migratory bird occurred in 2009, when US Airways Flight 1549 struck a flock of Canadian migratory geese shortly after takeoff from LaGuardia Airport in New York. Both of the plane’s engines failed, and Captain Sully Sullenberger was forced to pilot the plane into an unpowered landing in the Hudson River.
Between 2008 and 2017, the Australian Transport Safety Board recorded 16,626 bird strikes. In America, the Federal Aviation Administration reported 17,200 bird strikes in 2022 alone.
Where do bird strikes occur and what are the consequences?
According to the International Civil Aviation Organization, 90% of all bird strikes occur near airports. They generally occur when aircraft are taking off or landing, or flying at lower altitudes where most birds are active.
The impact of a bird strike depends on many factors, including the type of aircraft. The consequences can include engine failure, as happened on the Virgin Australia flight. This aircraft was a Boeing 737-800, which can fly to an alternate airport using a single engine.
Bird strikes can be fatal for smaller aircraft, especially single-engine aircraft. Since 1988, 262 fatal bird strikes have been reported worldwide and 250 aircraft have been destroyed.
How do manufacturers and pilots protect themselves from bird strikes?
Most bird strikes occur early in the morning or at sunset, when birds are most active. Pilots are trained to be alert during these times.
Radar can be used to track flocks of birds. However, this technology is ground-based and not available worldwide, so it cannot be used everywhere.
The two largest manufacturers of passenger aircraft, Boeing and Airbus, use turbofan engines. These use a series of fan blades to compress air before adding fuel and flames to create the thrust needed for takeoff.
A bird strike on one of these engines can cause severe damage to the fan blades and cause the engine to fail. Engine manufacturers test the safety of these engines by shooting a frozen chicken at them at full thrust.
The Australian Civil Aviation Authority’s circular on managing wildlife hazards describes what airports should do to keep birds and other animals away from the airport area. One method is to use small gas explosions that mimic the sound of a shotgun and are designed to deter birds from staying near the runway. In areas with high bird populations, airports can also use certain grasses and plants that do not attract the birds.
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