UFO Observation Report — San Luis Obispo, California, 8 April 1968

This document contains a collection of records regarding a UFO sighting reported on April 8, 1968, in San Luis Obispo, California. The primary witness, an Associate Professor of Mathematics, reported observing a vee-shaped pattern of yellow lights at approximately 2000 hours. The witness noted that the object appeared to be a large, noiseless aircraft, which moved in a steady, northwesterly direction. The witness explicitly compared the object to a jet but noted the absence of a fuselage or tail and the lack of engine noise. The report includes a completed 'Sighting of Unidentified Phenomena Questionnaire' (AF Form 117), where the witness provides details on the object's appearance, duration (approximately five minutes), and the lack of physical evidence. The witness also mentions that their ten-year-old son first spotted the object. The Air Force investigation, conducted by the Aerial Phenomena Office (Project Blue Book), concluded that the sighting was likely an aircraft, possibly an electrical aerial advertiser, noting the presence of several large airfields in the vicinity. The file also contains internal correspondence between the Foreign Technology Division and the Environmental Technical Applications Center to verify local weather conditions at the time of the sighting, which were confirmed as calm. The witness expressed skepticism about the object being a hot air balloon, citing prior experience with such devices, and maintained that the object's behavior and appearance were unusual.