OKLAHOMA CITY (AP) — A plane that crashed in northern Oklahoma, killing three Nebraskans, was nearly vertical when in struck the ground, according to a preliminary report released Tuesday by the National Transportation Safety Board.

“A witness in the area reported (seeing) the airplane come straight down in a right-hand nose down spin,” according to the report, and saw the tail of the aircraft detach from the fuselage.

“The wreckage was crushed… and fragmented and showed evidence of a near vertical impact,” according to the report based on an investigation of the crash site.

A final report on the probable cause of the crash is not expected for a year or more.

The March 17 crash near Pond Creek, about 80 miles (129 kilometers) northwest of Oklahoma City killed pilot William Lauber, 58, his wife, Christine Lauber, 58, both of Milford, Nebraska, and their daughter, Regan Lauber, 21, of Lincoln, Nebraska.

William and Christine Lauber were owners of Lauber Funeral and Cremation Services in Milford.

The funeral home’s director, Doug Wymore, said the family had been visiting another daughter in Austin, Texas, and were on their way home to Nebraska when the plane crashed.

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