Operation Snowbird
Operation Snowbird is, on the one hand, a real winter training program of the U.S. Air National Guard and, on the other, the name of a UFO legend stemming from a 1980s document now considered a forgery, according to which a craft of alien origin was tested in Nevada from 1972 onward.
The names Operation Snowbird and Project Snowbird are used for two unrelated things. One is a real winter training program of the U.S. Air National Guard; the other is a UFO legend about an alleged secret program that supposedly tested flying craft of alien origin in Nevada.
The legend
The source of the story is the so-called "Project Aquarius" document. This alleged secret briefing paper was shown to journalist Linda Moulton Howe in 1983 by Richard Doty, an agent of the Air Force Office of Special Investigations (AFOSI). According to the document, "Project Snowbird" began in 1972 for test flights of a recovered alien craft and continues to operate in Nevada. The story was later picked up by other ufology authors and was often linked to Area 51. Doty later acknowledged that he had also taken part in disinformation operations and that ufologists had been deliberately misled. The documents he circulated are now generally considered forgeries.
The real Operation Snowbird
Operation Snowbird is a long-running winter training rotation of U.S. Air National Guard units at Davis-Monthan Air Force Base in Arizona, where they train because of the more favorable weather. In March 1997, A-10 aircraft of the Maryland Air National Guard were conducting exercises as part of it. According to the official explanation, the flares they dropped caused one part of the phenomenon known as the Phoenix Lights.
Official and skeptical views
According to the official U.S. position, there is no program dealing with the possession or testing of craft of alien origin, and the "Project Snowbird" of the legend is not supported by any credible document. According to skeptics, the story was fed by speculation surrounding secret Cold War aircraft development and by deliberate disinformation. The topic is therefore more a part of ufology folklore than a verified historical fact.