[R] DE BOURG-SAINT-MAURICE (73) VERS PEISEY-NANCROIX (73) 19.06.2023

On 19 June 2023, between 18:22 and 18:30, a witness driving on the “Route des Espagnols” connecting Les Arcs 1800 to Peisey-Vallandry (Savoie) observed a dark object isolated in the sky. He stopped, got out of the vehicle and observed the phenomenon with the naked eye for several minutes, before filming and photographing it twice with his phone. Two hikers, unknown to the witness, were also seen observing the phenomenon. The object disappeared after eight minutes, when the witness resumed driving and a bend blocked his view. The witness describes the object as a cubic and hollow structure, dark gray with a metallic appearance, carrying under it a board-like element attached by a cord. The whole is perceived as silent, immobile or drifting very slowly, carried by the wind, without flashing, halo or light emission. The evidential quality* of the case is considered good, despite the late testimony (July 2025) of the only witness who reported the observation to GEIPAN. The duration of the observation allows a detailed and consistent description, supplemented by a video and two usable photographs. The strangeness felt by the witness is based on the perceived shape, long visibility and the absence of perceptible noise or movement, characteristics which differ from his references for known aerial objects. This impression is reinforced by the presence of an element suspended under the object, giving the whole an unexpected appearance. *According to the GEIPAN criteria, evidential quality is the amount of information collected for an account that is considered reliable and objectively established. The photographic analysis, however, qualifies some aspects of the description. On the images, the object does not show the geometric characteristics of a rigid cube: no sharply defined edge or angular structure is visible. Its shape appears rather rectangular with rounded edges, evoking more a soft surface or textile envelope than metal walls. The hanging element is clearly visible and confirms a main object with a suspended load, described in the source as typical of aerostatic devices, with a paraglider given as an example. A geometric estimate based on the characteristics of the camera and the apparent size of the object in the image indicates an angular dimension of about double that of the Moon (~1.2°). Using a range of possible distances including the witness’s estimate (between 100 m and ~500 m) and the estimate of angular elevation given by the witness, approximately 15°, results in an altitude of approximately 26 to 140 m above the observation point, and a probable actual size of approximately 2 to 10 m, consistent with the dimensions of a paraglider canopy (see Appendix 1: analysis by IPACO tool*). GEIPAN considers the behavior of the phenomenon decisive: to remain almost stationary for eight minutes, without noise or fall, necessarily implies an object carried by the air. At this altitude, a massive object would fall quickly; a motorized device would produce a noticeable noise; a drone would present visible structures providing lift. The absence of significant displacement indicates a very low horizontal speed, estimated to be less than one metre per second, compatible with a simple drift in a light wind or local thermal updrafts, frequent in mountainous areas. The weather data from the two nearest stations confirm a light prevailing wind of variable direction (4-10 km/h). The following hypotheses were examined and ruled out: conventional aircraft, drone, official weather balloon, astronomical phenomenon, particular atmospheric phenomenon, spacecraft or military equipment; all are incompatible with observed shape, lack of noise, very low apparent speed or daylight viewing conditions. The favored hypothesis is that of a light artificial object carried by the air: a handcrafted balloon, fabric canopy or similar improvised device, equipped with stabilizing ballast (the suspended element visible below the main shape). It could also be a bivouac flight, combining the use of a paraglider and the transport of the equipment needed for camping. The shape of the suspended device is indeed very similar to that of the bag-like harness into which the paraglider pilot fits, while the upper shape resembles a paraglider canopy seen from the side and almost directly below, giving a false impression of cubic form. The impression of rigidity and mass described by the witness is then interpreted as a perception bias related to distance, lack of depth markers and the significant visual contrast between the dark shade of the UAP and the very clear background of the sky. Air-filled fabric envelopes, such as that of a paraglider, can visually give an impression of deceptive hardness when observed at altitude. Research has been undertaken to determine whether there was an organized activity, public event, school project or artistic installation involving a release of flying objects in this area and on that date. No trace has been found in the local press, public announcements or institutional communications. GEIPAN also investigated whether a paragliding bivouac flight could have taken place in the observation area, which is part of an official paragliding launch area, without success. Note that the witness's lengthy delay in reporting his observation complicated the search. GEIPAN concludes that the observed phenomenon is most likely a light artificial object carried by local airflows, possibly a paraglider equipped for a bivouac flight, although its precise origin could not be established. GEIPAN classifies the case as "B": probable observation of an artificial object, such as a paraglider equipped for bivouac flying, carried by the wind. IPACO: GEIPAN image analysis and processing software (IPACO.fr).