RAF Squadron Leader Donald R. Higgin, assigned to USMC All Weather Fighter Squadron, El Toro MCAS, Calif, while flying an F3D-2 jet fighter at 15,000-16,000 feet on a heading of 240° magnetic (255° true) at 300 knots IAS and descending, saw a dark blue almost black gun-metal "glint" delta-shaped object, about 22-23 feet long and 20 feet wide, with a three fins of equal size and shape, at his 11 o'clock position just above the cockpit of his wingman flying another F3D-2 about 250 feet away. Object was on a head-on collision course but before Higgin could radio warning it passed under his wingman and between their aircraft, descending at a 25°-30° angle on a heading north of about 30°.

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