ANNECY-LE-VIEUX (74) 20.10.2002

GEIPAN continues to publish its complete archives on its public website, www.geipan.fr. These include older cases classified at the time as A, B, C or D that are now being re-examined solely to improve the conclusions. New technical tools (software) and the investigative experience acquired over the intervening years sometimes allow this re-examination to produce new observations or even a change in classification. This sighting, previously classified D and named ANNECY-LE-VIEUX (74) 20.10.2002, is among the cases recently reviewed. On 20 October 2002, at about 18:40, a couple observed from a terrace the silent movements of a group of 7 to 9 very small dark or black objects in the sky. The objects moved relative to one another. The observation with the naked eye and then the binoculars lasted about ten minutes. The group moved north-northeast at a speed estimated to be very low and at a constant altitude. Only one testimony was collected. The air-traffic control services of the area were contacted but no particular activity was reported. Two explanatory hypotheses for the phenomenon observed by witnesses were explored (see investigation report). The first concerns confusion with a group of black birds, evolving at high altitude in a migration corridor. Although the geographical and temporal situation of the witnesses, located in a migration corridor and observing in late October, during the migration season, supports this hypothesis, it remains fragile, especially for two reasons: - known and calculated data on UAP altitude, observation duration and speed do not match the characteristics of the birds recorded passing through that day; - and above all, the course is opposite the usual migration direction. The second hypothesis, that of confusion with a cluster of black balloons attached by strings, is, on the other hand, very well aligned with the data. A light southwesterly wind was blowing on observation day, in the same direction as the displacement of the UAPs, which was very slow. The known and calculated data on this velocity of movement, altitude and observation time are very well aligned with the hypothesis. Thus, with an altitude estimate of 500 m, we have a total angular displacement of approximately 67°, which is plausible in terms of the geographic configuration of the sites. Moreover, the movements of individuals within the group (approaches, separations, rotations, etc.) are explained by the fact that they are connected, more or less loosely, by strings. carried by the local wind, they move together as a group, but nevertheless remain subject to small local influences making them move randomly and independently of each other, within the limits imposed by their connecting strings. This variant of recreational balloon release is practiced and produces such effects, as shown on this video where the five balloons constantly change their relative position, while remaining confined to a restricted area, all being connected by strings. At the time of the sighting and initial investigation, GEIPAN had insufficient experience with this type of balloon release. The observation takes place on a Sunday evening at the end of the afternoon, which is conducive to a festive or recreational event of this type. The evidential quality is poor, with only 1 account collected, while several witnesses were present, and data, especially angular, are missing. No photo or video recording was made. GEIPAN ranks the case in "B": likely observation of recreational balloons.