Haneda AFB, Japan, August 1952August 1952

# Haneda Air Base, August 1952

On the night of August 5, 1952, control tower personnel at Haneda Air Force Base in Japan watched an unusual glowing object in the sky for nearly an hour. Two airmen first spotted it while crossing the flight line around 11:30 p.m., and they immediately brought it to the attention of other tower operators. Together, the four tower controllers observed the object through binoculars and described it as circular and brilliantly lit, with a constant glow across its entire surface.

Looking more closely, the operators noticed what appeared to be a large dark shape behind the bright light, roughly four times its diameter. Smaller lights ran along the lower edge of this darker form. The object seemed to fade and disappear toward the east, then reappear in the same general location about fifteen seconds later. The observers compared the central light's brightness to a weather balloon launched from the base, and said the UFO was far brighter, with a blue-white glow instead of the dim yellow light of the balloon. Throughout the sighting, no sound was heard, and the object appeared to move erratically, sometimes hovering, sometimes shifting position.

The tower alerted a ground control radar station at Shiroi Air Force Base, located about ten miles away. Two radar controllers there picked up a blip on their scope matching the tower's reported position and direction. They tracked the target moving in a circular pattern at varying speeds, sometimes hovering, sometimes moving at an estimated 250 to 300 knots. Around 12:12 a.m., the radar contact appeared to split into three smaller blips, each spaced roughly a quarter mile apart. An F-94 fighter jet was scrambled to intercept the object. The jet's radar operator managed to acquire a brief contact at about 6,000 yards before the target accelerated rapidly and disappeared from the radar scope. The jet crew saw nothing visually despite excellent visibility and an extensive search. At the same moment the jet lost radar contact, both the tower and ground radar also lost track of the object, possibly because it moved into an area filled with ground clutter that obscured radar returns.

The incident was unusual because radar and visual sightings correlated closely in time and location, yet neither the jet crew nor the radar operators at Shiroi could see the object, even though they were much closer to it than the tower personnel. The investigator noted that the moon was nearly full and positioned where its light might have reflected off a thin cloud layer or water, potentially creating a bright reflection visible from certain angles but not others. However, the precise nature of the object, its movements, and how three radar contacts could appear from a single target remained unexplained in the file.

The full case file, including witness statements and radar data, is reproduced below as held by the National Archives across 15 pages.