James B. Thomas killed in small plane crash near Newton in Lincoln County on May 25.

National Transportation Safety Board (NTSB) officials say it may be a while before they know what caused a deadly plane crash in Lincoln County.

According to the Federal Aviation Administration (FAA), the 1971 fixed wing, single-engine plane belonged to James B. Thomas from Denver. Officials say Thomas took off from the Laney Airport just minutes before the crash.

Authorities in Catawba County say Thomas was killed when the plane crashed in a wheat field near Balls Creek School Road in Newton. Investigators say he was the only person on board.

Friends told WBTV Thomas said he was just going to go up to fly for a little bit, and that he was in "good spirits" when he left. Investigators say it appears the aircraft flew straight into the ground after takeoff.

The plane, a Starduster II, is considered and experimental craft because it is built from a kit, not in a factory. NTSB official Robert Getz told WBTV that in his years of investigating plane crashes, he has never seen a problem with that type of aircraft.

FAA records show the plane was certified in February 2011.