How dangerous are drones to manned aircraft? A study by researchers at Bard College, in New York State, US, has found the reported incidents have increased rapidly over the past two years.
The researchers found 70 incidents in the first seven months of 2014, and 585 during the first seven months of 2015.
The study reviewed 922 incidents involving drones and manned aircraft in the US from December 2013 to September 2015. It found that 327 incidents or 35 per cent of the cases could be described as close encounters, defined as drones coming within 150 metres of aircraft.
In 158 of those cases, a drone came within 60 metres of an aircraft, and in 28 cases, the pilot had to manoeuvre to avoid a collision. There were 90 reported close encounters between a commercial jet aircraft and a drone, and 38 involving helicopters.
In the other 594 sightings, drones were spotted near or within manned aircraft flight paths but did not pose an immediate danger of collision.
The study found that incidents were more likely to involve multi-rotor unmanned aircraft than fixed-wing drones, and predominantly occurred far above the Federal Aviation Administration’s 400-foot ceiling for unmanned aircraft, often within five miles of an airport
Study co-author Dan Gettingger said, ‘Our hope is that this study can help engender a collaborative dialogue among stakeholders working on this issue.’