The examination and thorough analysis of UAP databases, even if not being able to furnish information on the physical nature of the investigated phenomenon, is able to furnish several important insights concerning the effective existence of the phenomenon and the way in which it is perceived by witnesses, its behaviour in space and time and its possible connection with geophysical and astronomical phenomena. Serendipitous discoveries can be done too, where it may happen that the “UAP variable” can be used by chance as a “probe” to investigate the behaviour of other variables of interest. Experience teaches that the analysis of UAP databases is scarcely useful when scientific expeditions on sites of particular interest due to a high frequency of sightings are effectively done. There seems to be no real “spatial recurrence” of the UAP phenomenon intended as such; nevertheless measurements of the electromagnetic field of the areas that have been involved in the more or less recent past are worth doing, in fact there are some reasons to think that “UAP flaps” occurred for a brief time in some specific areas – or even some isolated prominent UAP sightings – might be induced or triggered by some specific characteristics of the territory in which this has been occurring. The elusive and unpredictable nature of the UAP phenomenon (pretty much differently from the earthlight phenomenon) renders any effort to monitor it scientifically, extremely difficult, unless a very well trained team of scientists and engineers is able to enter promptly into action as soon as a new UAP flap occurs. Probably such strategy and tactics can reveal to be the most cost-effective in the attempt of acquiring scientific data from this “fringe phenomenon”, provided that the appropriate scientific instrumentation is available, well tested and professionally deployed and used.