THIEF RIVER FALLS  (AP) - A preliminary report from federal investigators says a witness who heard the crash of a small plane near Thief River Falls last week that killed three men from Wyoming could hear its engine ``screaming'' before he heard the impact.

The report from the National Transportation Safety Board says the three were killed shortly after the single-engine Cessna took off from Thief River Falls on a flight to Rawlins, Wyoming.

The NTSB says a hotel employee who drove the three men to the airport said the passengers had expressed concern about turbulence that was expected during the flight.

The pilot, 69-year-old Moy Wing, 27-year-old Brian Duke and 26-year-old Zach Ostertag died when the plane went down in a farm field Sept. 23. Thief River Falls is about 70 miles (112 kilometers) from the Canadian border.