In the video we see a rapidly moving object below the aircraft. When he saw the object in cellphone, the immediately put the camera down and looked out the plane; the object was gone by then.
Astronomer Alexis Astua estimated that the object was traveling at 3600 kilometers per hour. This is seven times the speed of the airplane.
See the footage at UFO Videotaped by Costa Rican Pilot, and be sure to add your comments.