Elsinore, CaliforniaMay 1954

On May 18, 1954, a Royal Air Force Squadron Leader named Donald Higgin was piloting an F3D2 aircraft near Oceanside, California, during a routine training exercise with a second jet. At around 12:40 p.m., as the two planes descended together at 15,000 feet, Higgin spotted what he thought was another aircraft approaching head-on from the eleven o'clock position, just visible over the nose of the other jet. He realized a collision seemed imminent.

Before Higgin could warn the other pilot, the object passed just under the second aircraft and between it and his own plane. For an instant, he saw it clearly. The object had a dark gun metal color and no visible markings. It measured roughly 22 feet long, about half the length of an F3D jet. It had a delta wing shape, meaning it resembled a triangle, with a third fin visible on top. The wing span was roughly equal to its total length. Higgin was struck by how shiny the metal looked. The object appeared to be heading roughly northeast (020 degrees) and descending at an angle of 25 to 30 degrees. Its speed seemed very high, at least as fast as the F3D and probably much faster. The entire encounter lasted only seconds. By the time Higgin could call out to his radar observer, Flight Lieutenant Ronald Dalton, the object had vanished to his left.

Higgin thought the other plane might have been hit and immediately checked with the second jet's pilot, Major R. Browning, by radio. Neither Browning nor his radar observer had seen the object. Dalton, Higgin's own radar observer, was looking down at the terrain when the incident occurred and also did not see it. The three aircraft were flying in formation at about 15,000 feet, roughly 10 to 15 miles south of Lake Elsinore, California. Both pilots filed signed statements and Higgin provided a sketch of what he had seen.

The Air Force concluded that while the object resembled a lenticular cloud (a lens-shaped cloud formation), a cloud at that altitude and of that appearance would not normally vanish so suddenly and would have been visible to the other crew members. For these reasons, the Air Force marked the sighting as unidentified. The complete case file, consisting of 7 pages as held by the National Archives, is reproduced below.