History of Flight
On November 18, 2018, about 2240 central standard time, a Cessna 441, registration N441CX, was destroyed when it impacted terrain near Harmon, North Dakota. The pilot, flight nurse, and paramedic were fatally injured. The aircraft was being operated as a Title 14 Code of Federal Regulations Part 91 positioning flight. At 2049, the crew was notified of a mission to fly from Bismarck Municipal Airport (BIS) to Sloulin Field International Airport (ISN) to pick up a patient and return to BIS. The pilot requested 50 gallons of Jet fuel. At 2159, weather documents were obtained. An instrument flight rules (IFR) flight plan was filed at 2227, estimating departure at 2234, cruising altitude 14,000 ft, en route time 45 minutes at 281 knots, with 3 hours 30 minutes of fuel and no alternate airport. Radar data showed takeoff at 2231, climb to 14,000 ft, then a right descending turn around 2239:30. Between 2239:30 and 2240:09, the airplane lost 7,800 ft of altitude. Radar contact was lost at 2240:18 as a primary target. No distress calls were received. Witnesses heard high-pitch, high-speed engine sounds before impact.
Meteorological Information
Weather conditions included a low-pressure system over Minnesota with a cold front extending into North Dakota. The Area Forecast indicated widespread marginal VFR and localized IFR conditions behind the cold front. Radar showed snow showers north and east of Bismarck. The Weather Depiction Chart showed IFR conditions due to low ceilings and visibility in snow. Upper air data supported nimbostratus clouds with snow and high humidity between 7,000 and 15,500 ft, suggesting light-to-moderate rime-to-mixed icing. Icing probability exceeded 90%. AIRMET Sierra and AIRMET Zulu were in effect for IFR and icing conditions, respectively. No weather watches or warnings were active.
Wreckage and Impact Information
The accident site was about 20 miles northwest of BIS, with wreckage scattered over 2,500 ft by 750 ft, oriented north-south. The north end contained both engines. Fuselage fragments and wings were in the middle. Lighter parts were found to the south. The empennage was east of the cockpit. The left engine was 225 ft north of the empennage; the right engine was 225–300 ft north and east of the cockpit. The right wing separated at the fuselage with leading edge crush damage; the aileron showed buckling. The left wing broke into two pieces with aft/downward crushing and black paint transfers. The left aileron was separated into three pieces with bending and crushing. Flight control continuity was confirmed from cockpit to ailerons, elevator, and rudder. Engine examinations revealed no mechanical malfunctions that would have prevented normal operation. No propeller failures were found.
Medical and Pathological Information
Autopsies of all three occupants were performed. The cause of death for each was listed as "multiple injuries." Toxicology testing of the pilot found no ethanol in vitreous, but 58 mg/dL ethanol in blood cavity, likely from post-mortem putrefaction. No drugs were detected, and samples were unsuitable for carbon monoxide testing.
Tests and Research
The enhanced ground proximity warning system (EGPWS) was removed and examined; no data could be retrieved. The pilot's cellular phone was damaged; forensic download showed it had been powered on multiple times. Text conversations in August and October revealed pilot concerns about a portable backup attitude heading reference system (AHRS) and a heading situation indicator (HSI) that precessed 25 degrees, with autopilot issues. A photograph from a previous flight showed the autopilot engaged in NAV and ALT modes at 25,000 ft. A Stratus-3 ADS-B receiver with AHRS capabilities was found in the wreckage but was not turned on.