Accident Overview
On September 30, 2012, at 0920 central daylight time, a McDonnell Douglas 369FF helicopter, registration N530KD, made a forced landing to a corn field near Decorah, Iowa. The helicopter sustained substantial damage. The airline transport rated pilot and a passenger sustained minor injuries. The helicopter was operated by Rogers Helicopters Incorporated, Fresno, California, on a repositioning flight under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and a company visual flight rules flight plan was filed.
Flight History
The pilot reported picking up the helicopter and the passenger on September 29 in Kearney, Nebraska, for a power line construction job in Green Bay, Wisconsin. They departed Kearney with full fuel (64 gallons/428 pounds). After a 50-minute flight to Columbus, Nebraska, the pilot added 32 gallons of fuel. They then flew to Fort Dodge, Iowa (1 hour 20 minutes), where the passenger added 48.95 gallons. That evening, the pilot flew the helicopter to his ranch near Jefferson, Iowa (48 minutes total: 14 minutes to ranch then 34 additional minutes). The next morning, September 30, the pilot flew back to Fort Dodge (14 minutes) and added 15 gallons. The fuel gauge indicated 305-310 pounds; the pilot could not visually verify because the fuel system design only allowed full-tank verification when topped off.
Departing Fort Dodge for Decorah, the low fuel caution light illuminated about 58 minutes into flight, indicating at least 35 pounds of fuel remaining. The pilot continued toward the airport, about 3 miles away. Approximately three minutes later, the engine flamed out. The pilot performed an autorotation to a mature corn field. Upon touchdown, the helicopter bounced and rolled over, coming to rest on its left side.
Post-Accident Examination
Federal Aviation Administration (FAA) inspection revealed the tail boom had separated, and the main rotor and tail rotor blades were damaged. The fuel tank was intact with no fuel odor; about two drops were drained from the fuel sump and approximately a quarter-cup from the tank.
At the request of the National Transportation Safety Board (NTSB) Investigator-in-Charge, the repair company conducted a detailed examination of the fuel system. No mechanical deficiencies that would have precluded normal operation were found. However, the fuel gauge and low-fuel caution light were not calibrated correctly. With 19 pounds of fuel in the tank, the gauge indicated two bar widths above the red dot (the 35-pound mark). With 35 pounds, the gauge indicated between the red dot and 100 pounds. The low-fuel caution light, designed to activate at 35 pounds, illuminated at 19 pounds.
The operator reported that the fuel-low caution light was inspected as part of a continuous airworthiness inspection on March 1, 2012. No maintenance was performed on the fuel quantity sensor system between that inspection and the accident.