Project Blue Book Case File
OTIS AFB, MASSACHUSETTSJuly 1952
Summary
On the evening of July 29, 1952, radar operators at Otis Air Force Base in Massachusetts tracked an unidentified object moving across the sky at high speed. The object appeared on radar traveling north to south at approximately 1,200 miles per hour. It was detected at an altitude above 22,000 feet. Visual observers on the ground also reported seeing the object, describing it as bright and moving in a straight line across a generally clear sky with scattered clouds.
The Air Force investigation that followed examined multiple witness accounts and radar data. Officers compared the timing and location of the sightings to determine what might have caused the reports. They checked weather conditions at the time and looked into whether any military or civilian aircraft or balloons were in the area.
The case file indicates the Air Force was unable to explain the sighting definitively. While investigators considered various possible explanations, including weather balloons and aircraft, the radar track and the speed at which the object was traveling presented challenges to these theories. The full case file, consisting of 9 pages as preserved by the National Archives, is reproduced below.
Reported location
OTIS AFB, MASSACHUSETTS
Date of incident
July 1952
State / country
MA / US
Page count
9 scanned pages
USAF evaluation
unidentified
Microfilm
T1206, Roll 13