Skilled pilots approaching a runway usually can’t see small unmanned aircraft systems (sUAS) encroaching on their airspace, and they virtually never detect motionless drones, a newly published study shows.
During an airborne human factors experiment, certificated pilots failed to see a common type of quadcopter during 28 of 40 close encounters, researchers with Oklahoma State University and Embry-Riddle Aeronautical University reported.
In other words, the pilots got a bead on the invading drone in 12 out of 40 cases, or only about 30 percent of the time. When the drone was not moving, the task became even more difficult. A mere three out of 22 motionless drones were spotted by the pilots. Drones were detected at distances of between 213 and 2,324 feet.
These findings, published in the International Journal of Aviation, Aeronautics, and Aerospace (IJAirport drone), illustrate a real and growing threat to aviation safety, said Dr. Ryan J. Wallace, assistant professor of Aeronautical Science at Embry-Riddle.
“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.”
Even in a best case scenario, if a drone was spotted at the study’s maximum detection range of 2,324 feet, the pilot would have only about 21 seconds to avoid a collision. “That might be enough time if the drone was hovering in one spot, but not nearly enough if it’s in flight, headed for the aircraft,” said Dr. Matt Vance, assistant professor of aviation and space at Oklahoma State. “The situation is far more dangerous when both aircraft are moving,” he said. “Our eyes are attuned to movement. When a drone is not moving, it becomes part of the background.”
An aircraft’s final approach for landing is an especially risky time for a drone encounter because “it can catch you unaware and you have little time to react,” explained Dr. Jon M. Loffi, associate professor of aviation and space at Oklahoma State. “You don’t have the altitude to maneuver safely, and if an engine ingests a drone, that could bring the aircraft down.”
The research examined what happens as a pilot prepares to land and switches from instrument-guided flight to visual flight. Pilot participants were selected from a collegiate flight-training program. During the experiment, pilots conducted an approach to landing in a Cessna 172S while a DJI Phantom IV quadcopter-type drone flew a scripted series of maneuvers along the approach path. Pilots were told that they might or might not encounter a drone. ■
An upper level high pressure system is expected to continue aiding well above average and potentially dangerous temperatures throughout the West into the first full weekend of September.