10 NM S Of Monterey Peninsula, Cal, September 1959September 1959

On September 1, 1959, two military pilots flying a T-33 jet trainer aircraft over the Monterey Peninsula, California spotted an unusual light in the eastern sky. Major John W. Sherwood Jr. and First Lieutenant Roy C. Gill were at 30,000 feet when they noticed what appeared initially to be another aircraft. The object was moving directly toward them at high speed. The pilots turned to keep it in view as it passed to the south of their position, at an estimated altitude of 40,000 to 50,000 feet. Major Sherwood observed faint bluish-green squares trailing behind the bright white light, though Lieutenant Gill, who was flying the aircraft, did not see them. The object was about as bright as a landing light and far faster than their jet. After moving westward over the Pacific Ocean, the light went out for about ten seconds, came back on briefly, then disappeared. The pilots watched it for three to five minutes total before it vanished.

The Air Force's initial assessment suggested the object was probably a high-performance aircraft, with the bluish-green squares attributed to the glow of an afterburner (a jet engine component that boosts thrust). The investigators requested detailed follow-up information from the witnesses, including drawings and clarifications about the object's altitude, course, and the precise timing of their observations. Major Sherwood provided a detailed written account explaining that he had never seen anything like the light's appearance in his flying career, which was why he and Lieutenant Gill decided to report it officially.

The full case file, comprising 13 pages as held by the National Archives, is reproduced below.