I don't go in for UFOs and such on this blog but for those who do the Condon Report, which I read many years ago, can be found online. This government-sponsored study of UFOs came to a negative conclusion but actually contained within it data that supported the existence of a real phenonema. For example, take a look at their conclusions regarding the classic McMinnville UFO Photographs:

This is one of the few UFO reports in which all factors investigated, geometric, psychological, and physical appear to be consistent with the assertion that an extraordinary flying object, silvery, metallic, disk-shaped, tens of meters in diameter, and evidently artificial, flew within sight of two witnesses. It cannot be said that the evidence positively rules out a fabrication, although there are some physical factors such as the accuracy of certain photometric measures of the original negatives which argue against a fabrication.