Accident Details
On July 26, 2018, at 2100 central daylight time, a Continental Copters Inc. Tomcat MK5A, registration N9005T, experienced a total loss of engine power while in cruise flight. The pilot executed an autorotation to a field and impacted terrain approximately six miles east of Le Sueur, Minnesota. The commercial pilot sustained minor injuries, and the helicopter incurred substantial damage. The helicopter was registered to and operated by Scotts Helicopter Service Inc under Title 14 Code of Federal Regulations Part 137 as a ferry flight not operating on a flight plan. Dusk visual meteorological conditions prevailed for the flight, which departed from Hastings, Minnesota, at 2009 and was destined for Le Sueur Municipal Airport (12Y), Le Sueur, Minnesota.
Pilot Statement
The pilot reported that during the preflight inspection, approximately 23 gallons of 100 low lead fuel were aboard, which he considered sufficient for the flight. He estimated fuel consumption at 15–17 gallons per hour and a typical flight duration of 45 minutes to one hour. Prior to departure, the fuel gauge indicated close to three-quarters full. About 5–10 minutes after departure, the pilot realized he had forgotten to sump the fuel tank, so he landed to perform the sump. He then continued the flight. Approximately seven miles east of 12Y, at an altitude of 400–500 feet above ground level and a speed of 60 knots, the engine sputtered, regained power momentarily, and then ceased operation. The pilot performed an autorotation to a field, and the helicopter impacted terrain.
Aircraft Information
The type certificate for the helicopter was held by the operator. According to the type certificate data sheet, the helicopter's fuel capacity was 41 gallons. The last annual inspection was performed on February 14, 2018, by the operator's maintenance personnel.
Postaccident Examination
Postaccident examination by a Federal Aviation Administration inspector found no useable fuel aboard the helicopter. The fuel gauge indicated a little over one-quarter tank. The fuel transmitter, a resistive type manufactured around 1974 by Stewart Warner, had a corroded resistive element. Testing with an ohm meter revealed that its resistive values were uncorrelated to float position. A new fuel transmitter from the operator's parts department was also tested; its resistive values corresponded correctly to float position and showed no anomalies. The inspector noted that the owner/operator stated, "pilots don't depend on those gauges – but they always stick the tank before departing so they know what they've got!"