correspondent renney marsh. what are you learning? they re in the sky by the hundreds. flying dangerously close to passenger planes. the number of close calls reported has more than doubled and tonight both the faa and pilots are expressing concern. tonight, the faa is sounding the alarm about a dramatic spike in the number of close calls between planes and drones. so far this year, pilots have reported more than 650 drone sightings. compared to 238 in all of 2014. yeah, we were on the final 31 right, 800, 900 feet, 100 feet below us was a drone. it absolutely is an unnecessary risk. especially during@provo phase, we re busy in the cockpit. one of the last things we re going to expect is a green encounter. reporter: despite faa rules that forbid flying above 400 feet near commercial planes or