Why are pilots worried about drones?
Pilots and Air Traffic Control operators are unable to establish visual contact with drones in the air. This poses great safety risks, as drones that come into contact with an airplane engine could cause serious problems.
Bird strikes are not uncommon relatively speaking, and passenger aircraft can fly with a single engine. But there are concerns however, that a metallic object containing lithium batteries could cause failure that cannot be contained, with debris impacting on the air frame.
Not to mention the danger of a drone crashing through a cockpit window. So an increasing amount of drone traffic means an increasing potential risk of lethal accidents if they cannot be seen and are not regulated in a safe and efficient manner.
Drones are hard to spot in the air