Kean points out that countries like France and Chile maintain official government agencies to handle this kind of investigation, but the United States does not. The Federal Aviation Administration simply advises pilots to report any incidents to private UFO groups or to local authorities if they believe property or people are threatened. This official lack of interest is a concern, Kean says, because of the potential dangers posed by some incidents.
In one case, on Nov. 7, 2006, a dozen or so United Airlines workers at Chicago O'Hare International Airport spotted a gray metallic-looking disk apparently hovering for several minutes above an airport gate before shooting upward and vanishing, leaving a hole in the cloud cover. The witnesses, including mechanics, pilots, and supervisors, shared their accounts with the Chicago Tribune, which covered the story. The FAA suggested they had seen a "weather phenomenon" and didn't formally investigate, Kean says, despite the potential intrusion of an unknown craft in the airspace of one of the nation's busiest airports.
"The FAA's mission does not involve the investigation of UFOs," says agency spokesman Tony Molinaro, adding, "Our employees didn't see anything unusual and nothing caused any operational problems that day."
In fact, many experts are more concerned about the hazards these sightings pose to aviation than about the potential for alien involvement. When flight crews are distracted by what's going on "outside the window," they are focused on that and "not flying the airplane anymore," says Richard Haines, a former senior research scientist at NASA's Ames Research Center who is now chief scientist of the National Aviation Reporting Center on Anomalous Phenomena, a private research group focused on flight safety related to unidentified aerial phenomena. Kean agrees, particularly since pilots have reported encountering some of the more bizarre sights in the sky, including metallic disks, massive cigar-shaped craft, green spheres, and highly agile objects that seem to stop, accelerate, and turn in response to a pursuing pilot's maneuvers.
Haines believes only about 5 to 10 percent of incidents ever get reported, in part because professional pilots fear ridicule and potential damage to their careers.
"I really think we need to make it permissible to study these things without risking your reputation," says John Alexander, a retired U.S. Army colonel and author of the 2011 book UFOs: Myths, Conspiracies, and Realities. As to the bigger issue of what actually is behind the largely unexplained incidents, or the possibility of extraterrestrial involvement, the debate is unlikely to be settled anytime soon.
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