Bug off! The surprising impact dead bugs have on aircraft efficiency
July 15, 2025
The splattered remains of insects on aircraft surfaces have a surprising impact on aviation sustainability. As they accumulate, dead bugs can lead to increased drag, resulting in a measurable reduction in fuel efficiency.
Dead bugs on an aircraft’s laminar flow area can increase fuel consumption by 1.1% to 4.4%, and as few as 400 insects can create measurable drag.
The threat is higher during insect season. Bug splatter accumulates on the nose, wings and forward sections of aircraft, interfering with airflow.
To counteract the drag insects produce on engine thrust and wing lift, and prevent excessive fuel burn, operators must clean the aeroplane.
A study by the German Aerospace Centre (DLR) found that the accumulation of 400 insects on an aircraft can increase fuel consumption by 1.1% for shorter flights of approximately 750 km and up to 4.4% for longer flights.
“The threat of contamination is typically limited to operational phases close to the ground,” the study states.
Between 50% and 60% of the dead bugs on aircraft stick during the ground run, with more bug splats collected at low altitude during climb-out, final approach, and landing.
The likelihood of bug splats reduces significantly once the aircraft climbs above 1,000 feet. However, dead bugs tend to stick hard, and will impact the airflow throughout the flight.
Dead bugs on aircraft can drag down airline profitability
The drag dead bugs cause on aircraft is nothing in the great aerodynamic scheme of it all. But in a world where fuel accounts for
“Even a 1-4% increase in fuel burn due to insect contamination can cost airlines millions of dollars, especially for fleets with many daily flights,” says Veronika Andrianovaite, Chief Commercial Officer of Nordic Dino Robotics, a firm that specialises in aircraft cleaning equipment.
Insect activity around aircraft differs by region and season. “In Europe, for instance, it’s spring and summer. In many parts of Asia, it is linked to the monsoon season, which typically brings increased rainfall and humidity and can last until October,” says Andrianovaite.
Cleaning aircraft to remove insect debris adds to the time the aircraft spends on the ground, although tools like washing robots can reduce the turnaround time.
“For wide-body airliners like the Airbus A330 and the Boeing 777, the time spent on exterior cleaning can be shortened from 8 to 4 hours, and for narrow-body jets like the Boeing 737, the required aircraft-on-ground (AOG) time is reduced from 3 to 1 hour,” Andrianovaite says.
NASA tackles the threat of dead bugs on aircraft
Despite extensive research, insects continue to bug aerospace engineers. Scientists have been trying to counter the bug threat for decades.
In 2013, a dedicated team of experts at NASA’s Langley Research Centre in Virginia examined the application of different non-stick coatings to prevent insect remains from adhering to aircraft wings during flight.
“It’s major enough that people have been trying to solve this as far back as the 1960s,” Mia Siochi, of the Advanced Materials and Processing Branch at Langley, said in an interview with Science Daily.
In testing, the team used a “bug gun” in the Basic Aerodynamic Research Tunnel, or BART—a small wind tunnel—to test how various materials and coatings respond to insect splats.
“We’re shooting bugs at about 150 mph as we try to mimic takeoff and landing speed,” Siochi said.
The team found that some coatings can shrink the area to which insect splats adhere by as much as 90% and reduce the build-up by 40%. Still, tests continued with no silver bullet found.
The NASA team also collaborated with Boeing engineers and pilots during the EcoDemonstrator flights of 2015 to gather vital bug data. They tested bug-repelling coatings on two of the leading edge slats on the aeroplane’s right wing. Uncoated surfaces provided a baseline of insect accumulation rates. Then they flew untreated control surfaces along with engineered surface samples of five bug-resistant coatings.
Beyond determining which coating was most effective in reducing the amount of bug residue, NASA researchers also aimed to gather data that would help engineers measure how reducing the size and specific locations of bug strikes can benefit laminar flow and improve fuel efficiency.
