Unconventional Aircraft Sighted at Portsmouth, New Hampshire — 24 July 1951

This document is a formal report of investigation conducted by the Office of Special Investigations (OSI) regarding an unconventional aircraft sighting that occurred on 24 July 1951 near Portsmouth, New Hampshire. The primary witnesses were a Captain and a Corporal from the 4675th Air Base Squadron, Hanscom Air Force Base, who were driving north on U.S. Highway No. 1 at approximately 1910 hours. The witnesses reported observing a long, tube-like object, estimated to be 100 to 200 feet in length with a thickness one-fifth of its length. The object was described as having a fin on one end and a surface that resembled fused glass, appearing grayish to invisible in color, and covered with black polka-dotted spots. The object traveled from east to west at an estimated altitude of 1,000 to 2,000 feet and a speed of 800 to 1,000 mph. The witnesses noted that there was no exhaust or vapor trail, save for a swath resembling a weak rainbow, and no sound was heard. The object remained in view for approximately 20 seconds before disappearing into a cloud bank. The investigation was predicated on a verbal report provided by the Captain, who was familiar with AFOIC-CC-1 reporting procedures. The investigating officer, Special Agent Edward A. Bray, interviewed both witnesses. While the Captain provided the primary description, the Corporal corroborated the sighting but admitted he could provide no further information and relied on the Captain's judgment regarding the object's speed and altitude. The investigator explicitly noted that the Corporal lacked the background and experience to accurately estimate the performance of such a fast-moving object. The report includes weather sequence data for the area and confirms that no physical evidence or photographs were available. The case was officially closed by the OSI following the preparation of the standard Air Force Form 112 for the Air Materiel Command. The document is marked as unclassified and was subject to standard downgrading and declassification procedures.