WASHINGTON (AP) A supposed alien spacecraft discovered near Roswell, N.M., 47 years ago likely was a secret Army Air Force balloon designed to monitor Soviet nuclear testing, the Air Force concluded Thursday. The Air Force in a report on the ``Roswell Incident'' said contrary claims in a wave of sensational books and television specials are ``undocumented, taken out of context, self-serving or otherwise dubious.'' The July 1947 discovery of wreckage on a ranch near Roswell has been at the center of longstanding disputes between UFO advocatesand the government over whether the Air Force has been hidingevidence about alien spacecraft discoveries. The Air Force began its investigation earlier this year amidcharges that it was covering up the truth. The material found near Roswell consisted of foil-wrappedfabric, wooden sticks, rubber pieces, and small I-beams withstrange markings on them. A local newspaper at the time reported: Air Force Captures Flying Saucer On Ranch. ``The Air Force research did not locate or develop any information that the `Roswell Incident' was a UFO event,'' wroteCol. Richard Weaver, author of the report. ``The most likely sourceof the wreckage ... was from Project Mogul balloon trains.'' Although it rejects UFO and alien theories, the report,nevertheless, suggests an interesting ancestry to the Roswellwreckage. Project Mogul was a top-secret venture to develop balloons thatwould carry sensing devices aloft and alert the U.S. military ofany Soviet nuclear tests. It was a high priority at a time when the government was concerned that its monopoly on nuclear weapons mightbe threatened. The Roswell Incident also occurred in the midst of the so-called UFO wave, the surge of interest in unidentified flying saucers,presumably from other galaxies. Shortly after the incident,officials in what was then the Army Air Force dismissed the flying saucer speculation saying that the wreckage found near Roswell wasa weather balloon. There the matter stood until 1978 when the supermarket tabloid National Inquirer reported that Maj. Jesse Marcel, the Army AirForce intelligence officer who brought in the wreckage, claimed he had discovered UFO debris. A series of books followed advancing the UFO theory and accusing the Air Force of coverup. The Robert Stack-hosted television show,``Unsolved Mysteries,'' aired a recreation of the Roswell incidentand other television shows followed suit. According to the AirForce, a made-for-TV movie is in the works. ``From the rather benign description of the `event' and the recovery of some material as described in the original newspaper accounts, the `Roswell Incident' has since grown to mythical, ifnot mystical, proportions,'' Weaver wrote in the Air Force report. Weaver conceded that debunking conspiracy theories is a no-winbusiness because ``pro-UFO'' elements would simply dismiss thereport as part of the coverup. Rep. Steven Schiff, R-N.M., began pressing the Pentagon last year to declassify documents relating to Roswell. The Air Force appears to have expended considerable energy onthe report. Dozens of people, including several who were in Roswell and involved in the discovery of the wreckage, as well as veterans of Project Mogul, were interviewed. Investigators also combed archives for material relating to UFOs. In one example of the extent of the effort, the Air Force tracked down the original photo negatives of newspaper pictures showing the wreckage and sent them to ``a national level organization'' for digital analysis. This probably refers to the National Ph Interpretation Center, a super-secret branch of theCIA. The analysis found that the photos were of ``insufficient quality'' to produce substantive results. Walter Haut, a volunteer at the UFO Museum at Roswell, a center devoted to gathering information on this and other UFO incidents,rejected the Air Force conclusions. ``I feel very strongly about it,'' Haut said. Referring to those who made the original UFO claim, he said, ``We're not talking about flaky people.''