North American/Schwamm AT-6F accident near Fitchburg, Massachusetts, November 6, 2010

The NTSB's narrative final · quoted from the NTSB record

The pilot was performing a local, revenue sightseeing flight with a passenger in the aft seat. The flight was recorded on a glareshield-mounted personal video recorder. About 12 minutes into the flight, the pilot commented about an unspecified problem; however, the flight continued. Conversation regarding the airplane’s fuel state indicated that there was adequate fuel on board for the flight. After air work and sightseeing, the flight returned to the local traffic pattern. After turning onto final approach for landing, the engine completely lost power. The pilot was unable to restart the engine, and the airplane crashed short of the runway. Postaccident examination of the carburetor revealed a visible crack in the soldered seam on one of the metal floats. Although there was some impact damage to the carburetor, the cracked float was located inside a fuel chamber that was undamaged. Further examination of the float fracture revealed that it was the result of a dent in the float. The fracture surface was coated with a lead-based corrosion product that was also on the inside of the float, suggesting that the crack had been open and corroding for an extended time period. It is likely that the crack in the float provided a fuel path that allowed the float to fill with fuel, resulting in a carburetor malfunction. Examination of the airplane’s records did not reveal documentation of recent carburetor maintenance.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.