LAWRENCEVILLE, Ga. -- The family of Judith Kirchner somberly walked around what used to be their home Sunday afternoon. In an almost unbelievable accident, a plane crashed into their house on Walker Street Friday afternoon. Investigators said there are no obvious reasons why.

“We haven’t made any determinations yet, mainly because of all the destruction with the aircraft,” says Butch Wilson, an investigator with the NTSB.

In one piece, the Cessna would fill the large tent in the yard. Instead, the pieces that are left barely cover the ground. Wilson said it is the worst crash site he has worked in terms of what is left of the plane. In this case, there is almost nothing left.

Investigators said they have found nothing that indicates engine trouble. There were also no pieces of the plane falling from the sky. Witnesses said the plane came in loud and fast. Investigators said it was sideways and traveling about 230 miles per hour when it hit. The plane cartwheeled and hit the house.

The pilot, James Wardlaw, was flying from Gwinnett to Sparta, Tennessee. Investigators still need to look at his record, the radar and if Friday’s poor weather conditions were a factor.

“Did anything go wrong with the airplane? Was there mechanical failure or something? All that evidence at this point in time has likely been destroyed, so we will never be able to make that determination,” said Wilson.

Sunday, the NTSB completed their on-site investigation. The pieces of the plane will be stored by an insurance company with the NTSB able to access them if necessary.

The investigation is expected to take six months to complete.