Clark AFB, Phillipines, November 1948 - Incident Number: 208November 1948

On November 17, 1948, at 2:30 p.m., two fighter pilots at Clark Air Force Base in the Philippines spotted an unusual object in the sky. From their position on the ground, they watched an irregular white mass that looked like an aircraft had exploded, leaving a thick smoke column behind it.

The object appeared to be at about 30,000 feet altitude and was connected to a curved exhaust trail that looped in a corkscrew pattern. The trail extended between one and ten miles in length. Unlike a normal vapor trail from an aircraft, this one seemed to have a sudden burst origin and then gradually tapered off. Within approximately three minutes, the entire mass and trail had dissipated into the atmosphere like smoke, scattering thinly as it dispersed. The sky around the sighting was clear and cloudless, and both witnesses were certain the object was not a cloud formation.

The pilots noted the phenomenon resembled either a rocket or jet exhaust rather than a standard aircraft vapor trail. They estimated it was heading either 120 or 300 degrees (roughly southeast or northwest), depending on where it originated. The Air Force received the report through official channels and recorded the observers' descriptions in detail.

According to an Air Force weather analysis attached to the file, the limited information available could be explained as referring to the trail and explosion smoke left by a fireball, and the observations were noted as consistent with that interpretation. However, the file indicates no definitive explanation was determined.

The full case file, comprising 19 pages as held by the National Archives, is reproduced below.