As a skeptical UFOlogist, I have long been struck by how many reported UFOs turn out to be IFOs (identified flying objects) attributable to the U.S. Government. New evidence for this trend constantly appears, and there are several major types of such IFOs.
The Central Intelligence Agency (CIA) has estimated that over half of the UFOs reported during the 1950s and 1960s were actually American spy planes, the U-2 (1957—present, one of the first to fly out of the secret “Area 51” test facility) and the SR-71 Blackbird (1966—1990, a tailless aircraft with an odd cross section). According to an article in the March 2009 Popular Mechanics, other UFO-impersonating craft include the triangular-silhouetted F117A Nighthawk stealth fighter (1983—2008) and the B-2 Spirit (1997—present, whose flying-saucer profile makes it “a UFO report waiting to happen”). Two others—a blimp-like P—791 airship and the supposedly canceled RQ-3 Darkstar—fuel speculation about other secret missions and possible UFO sightings.
The first UFO to be photographed—on July 4, 1947, in Seattle—was revealed to be a weather balloon, as were numerous other UFOs. Two very famous cases—the Roswell Incident of 1947 (involving a crashed UFO and the alleged retrieval of its small humanoid occupants) and the Mantell Incident of 1948 (in which a plane went down following an encounter with a UFO—were due to secret balloons. The Roswell crash turned out to be that of a spy-balloon array—part of Project Mogul, used in an attempt to monitor anticipated Soviet nuclear tests. As to the death of Capt. Thomas Mantell, he chased what is now known to have been a 100-foot-diameter Skyhook research balloon. His plane not having been equipped with oxygen, flew too high. (See Edward J. Ruppelt, The Report on Unidentified Flying Objects , New York: Ace Books, 1956, 46—56, 160—163; Joe Nickell, “Return to Roswell,” Skeptical Inquirer , Jan./Feb. 2009, 10—12.)
Rocket launches, as well as common satellites, have been responsible for UFO reports. Also among the many nocturnal-light UFOs are meteor impostors in the form of man-made material re-entering the earth’s atmosphere. This includes such objects as rocket bodies and de-orbiting satellites, all of which burn up on re-entry, usually producing spectacular displays. (See Allan Hendry, The UFO Handbook , Garden City, N.Y.: Doubleday, 1979, 41—45.)
Designed for a number of strategic purposes (such as illuminating target areas or tricking enemy antiaircraft missiles), strings of parachuted flares dropped in military exercises have produced dramatic UFO flaps. One—referred to as “The Phoenix Lights”—occurred on the night of March 13, 1997. The lights appeared over the Estrella Mountains. The U.S. Air Force initially denied responsibility but eventually acknowledged that A-10 pilots from the Maryland Air National Guard had dropped illumination flares left over from a training exercise. (See “UFOs Over Phoenix: Anatomy of a Sighting,” Discovery Channel, Oct. 26, 1997.) A more recent flap occurred around Stephenville, Texas, on January 8, 2008. It turned out to have been F-16s on training maneuvers that included dropping flares of up to two-million candlepower each. (See James McGaha, “The Stephenville Lights: What Really Happened,” Skeptical Inquirer , Jan./Feb. 2009, pp. 56—57.)
Of course, there are many other causes of UFO reports, such as atmospheric phenomena, meteors, hoaxes, commercial and private aircraft, and so on and on. Among the unlikely explanations are extraterrestrial craft, not one of which has ever been proven to exist.