Details of Disappearance
Frank was last seen in Springdale, Utah on September 17, 1961. He was part of a group of 26 hikers from northern Utah who were caught in a flash flood of the Virgin River at the Zion Narrows.
The bodies of three of the hikers, a man and two teenage boys, were found the next day. Two of the bodies were nearly ten miles from the point where they'd been struck by the floodwaters, which had the river running about fifty times higher than normal. The search for the remains of Frank and his best friend, seventeen-year-old Alvin Dunyon Nelson, was called off after a week. A photo of Alvin is posted with this case summary. The other hikers survived.
In 2006, a swimmer in the Virgin River found the top part of a human skull on the riverbank. In 2012, it was identified through DNA as Alvin's remains; it was the only part that was ever located. Frank remains the only person still missing as a result of the flood. His body is presumed to still be somewhere in the canyon.