Incident #171 — Moscow, USSR — 3 August 1948

This document contains intelligence reports and correspondence regarding Incident #171, a sighting of an unidentified aerial object over Moscow, USSR, on 3 August 1948. The primary witness was an experienced American newspaper reporter who observed a long, narrow, bright, and shiny object at a very high altitude near sunset. The object moved in a southwest-northeast direction at a high but not excessive speed. The witness reported that the object appeared metallic, lacked visible wings, and made no sound. While a Russian acquaintance who also observed the object identified it as a rigid airship, the reporter doubted this conclusion due to the object's high speed. Official intelligence assessments from the Technical Intelligence Division concluded that there was no astronomical explanation for the sighting. Analysts suggested the object could have been a jet, a conventional airplane, or a dirigible, noting that atmospheric conditions and fore-shortening could cause aircraft to appear unusual. The document also references a broader context of Soviet interest in the American 'flying saucer' phenomenon, noting that the Central Party Committee in Moscow was conducting a secret study on the subject, as well as on reports of rockets over Sweden. The file includes internal correspondence between military intelligence offices regarding the need to continue follow-ups on such reports under the provisions of Project Sign.