US Navy Files - UAP Incident Summaries (1948-1955)

Three summary volumes from the U.S. Navy archive 38, covering the critical 1948-1955 era. The summaries document UAP sightings by naval aviators, destroyer crews, and patrol aircraft over the Pacific and Atlantic oceans. Many of the original reports were filed under "pyramid apex" classification — the Navy's designation for unprecedented material. Released through PURSUE Release 1 on May 8, 2026. PURSUE Release 5 added the Naval Photographic Interpretation Center's 1953 film analysis, which measured two 16mm films shot in Utah in 1952 and Montana in 1950 frame by frame. It ruled out birds, aircraft and balloons on the basis of velocity and acceleration computations, and found the objects "of a nature which we are not able to identify in terms of natural phenomena or commonly known man-made objects."