ST. LOUIS–In a preliminary report issued Friday, federal investigators probing the January 8 plane crash in Defiance, Mo that killed two pilots heading for Denver say the debris path left behind stretched the length of more than three football fields.

The National Transportation Safety Board said the Beech 58 aircraft piloted by George King and Amanda Youngblood, both from Ohio, climbed to 8,000 feet after takeoff from Spirit of St. Louis Airport in Chesterfield before descending. “Broken tree limbs indicated the airplane was in a steep descent at impact and the debris path was about 320 yards long,” the report states.

The pilots were flying for Airnet II, a Columbus, Ohio company that specializes in transporting dangerous cargo, but the plane was empty. They were heading for Denver to pick up cargo and return to St. Louis. NTSB investigators have previously said the pilots were certified for instrument flying in inclement weather. The flight plan filed indicated overcast skies with a ceiling of 1,000 feet. While investigators have said ice that night was not a factor, weather in general has not been ruled out.

Despite the extended debris field, it still took searchers two hours to find the wreckage in rugged terrain.

FOX2’s Andy Banker contributed information for this story