In the not too distant future, drones will be all over the skies, delivering packages, taking photos and videos and serving a slew of yet to be discovered purposes. They may also pose a danger to pilots and their passengers.
Particularly because approaching ones are hard to spot, even for skilled pilots.
Pilots have difficult seeing drones as they approach the runway
A new study conducted by researchers from Oklahoma State University and Embry-Riddle Aeronautical University reveals pilots approaching a runway usually couldn't spot small drones encroaching on their airspace. When the drone was motionless the pilots rarely saw it at all.
"Dangerous close encounters between aircraft and drones are becoming an increasingly common problem," said Dr. Ryan J. Wallace, assistant professor of aeronautical science at Embry-Riddle in a press release highlighting the work. "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."
According to Wallace, there are more than 1.4 million drones registered to fly in the U.S. Many more are unregistered, he said. The number of drones is only expected to proliferate in the coming years, posing more risk to pilots.
Pilots spotted drones only 30% of the time
The researchers conducted an airborne human factors experiment in which certified pilots failed 28 out of 40 times in spotting a common type of quadcopter coming into their air space. They only spotted the drones 30% of the time. When the drone was motionless only 3 out of 22 were discovered.
The researchers reported the pilots saw the drones between 213 and 2,324 feet. Even if the pilot saw the drone at 2,324 feet, the pilot would only have 21 seconds to react. The pilot is apt to get out of the way of a motionless drone, but it's not clear if the pilot could avoid a collision with a moving one.
"The situation is far more dangerous when both aircraft are moving," Dr. Matt Vance, assistant professor of aviation and space at Oklahoma State said in the news release. "Our eyes are attuned to movement. When a drone is not moving, it becomes part of the background."
Is tracking drones the answer?
Next up the researchers are testing the pilot's ability to spot drones with an electronic pinging device affixed to them. It uses ADS-B or automatic dependent surveillance-broadcast technology to track the aircraft. The researchers want to see if this can help pilots spot the drones and avoid a crash. This technology is slated to become a requirement for any aircraft in airspace near airports beginning in January but doesn't apply to drones.