In light of recent reports by aircraft crews encountering drones in flight near airports, Global Traveler is calling for a ban on the unmanned aircraft.

Unlike the remote-controlled airplanes of previous generations, drones, or unmanned aerial vehicles, are technologically advanced and capable of flying at higher altitudes. Land-based operators can pilot drones via remote control, but the aircraft can also be programmed to fly independently and to navigate via GPS.

On Sunday, the crews of four airliners on approach to Newark Liberty International Airport — Delta Air Lines, ExpressJet and two United Airlines flights — each reported sighting a drone operating at 2,000 to 3,000 feet. None of the flights took evasive action and all landed safely with no delays.

On July 31, the crews of two planes landing at John F. Kennedy International Airport each reported a drone sighting. The crew of a Delta flight coming in from Orlando reported seeing a drone about one-quarter mile from the aircraft; the pilot of a JetBlue flight arriving from Haiti said a drone passed just below the nose of the aircraft at about 800 feet.

While drones have practical applications ranging from real estate photography to crop monitoring, and the FAA requires anyone operating a drone within five miles of an airport to notify the airport operator and control tower, the risk of an inadvertent collision — or a planned attack — far outweighs the benefits.