CHADRON - A preliminary report from federal aviation safety officials did not list a cause of a small plane crash in western Nebraska last week that killed three people.

The report from the National Transportation Safety Board released Wednesday did relay what two witnesses to the crash saw. One witness, located at the Chadron airport, told officials he saw the plane as it was preparing to land suddenly drop nose-down behind a tree line. Another witness just northeast of the crash said she heard the plane sputter, as though it was losing power, before the crash.

The July 24 crash killed 25-year-old Duncan Brown of California, and his parents, Damon and Sarah Brown.

The flight originated at Oshkosh, Wisconsin, and was destined for Chadron.