A new study by researchers with Oklahoma State University and Embry-Riddle Aeronautical University is showing the danger drones pose for pilots.
The study, published in the International Journal of Aviation, Aeronautics, and Aerospace, looked into drones encroaching airspace near runways and found close calls between drones and commercial planes are on the rise.
Researchers said if an engine took in a drone, it could bring a plane down.
They said during an experiment pilots failed to see a moving drone during 28 of 40 tests. For a drone that hovered without motion, only 3 of 22 were spotted by pilots.
“Our eyes are attuned to movement. When a drone is not moving, it becomes part of the background,” said Dr. Matt Vance, assistant professor of aviation and space at Oklahoma State University.
Researchers said drones are especially dangerous in the final approach for landing. They said a drone can catch pilots unaware, giving them little time to react and not enough altitude to safely get out of the way.
“Dangerous close encounters between aircraft and drones are becoming an increasingly common problem,” Wallace said. “Statistics on pilot sightings of drones continue to increase year over year, and what is being reported by pilots is probably just the tip of the iceberg. The vast majority of the time, unmanned aircraft are not being seen by pilots.”
Researchers pointed to a recent close-call that happened to a commercial crew on approach to Boston’s Logan International Airport. The crew reported a drone at about 3,500 feet above ground level – higher than U.S. Federal Aviation Administration regulations allow. The event took place a week after another crew spotted a drone after takeoff from the same airport. Luckily the crew spotted both before it was too late.
The study said there are 1.4 million registered drones in the United States, but many more unregistered with no reliable way to track drone flights.
While the FAA has made strides to secure and control airspace from drones, the study says FAA's efforts have been met with mixed results.
The research team’s next project will involve rigging a drone with an electronic pinging device, which uses automatic dependent surveillance-broadcast technology to track aircraft. The study will assess whether the technology helps pilots pinpoint and avoid a collision with the drone.