History of Flight
On October 23, 2023, at 1611 central daylight time, a Piper PA-46-350P airplane, registration N92884, sustained substantial damage in an accident near Pierre, South Dakota. The pilot sustained serious injuries, and the passenger sustained fatal injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
According to the pilot, before takeoff from Pierre Regional Airport (PIR), the airplane was fueled with 10 gallons, bringing the total fuel on board to 100 gallons for the planned flight to Steamboat Springs, Colorado. The pilot reported that before takeoff, the header fuel tank contained 11 gallons of fuel, fuel boost pump No. 1 was selected, the fuel transfer switch was in the AUTO position, and the fuel selector was in the right fuel tank position. No anomalies were noted during engine start, takeoff, and initial climb.
While climbing through about 11,000 ft mean sea level (msl), air traffic control cleared the pilot to flight level 220. At approximately 12,000 ft msl, the engine experienced an abrupt loss of power, confirmed by a loss of torque and engine compressor turbine rpm (Ng). The pilot reported no cockpit warnings or abnormal indications before the power loss. He declared an emergency and executed a 180° turn back to PIR.
During the emergency descent, the pilot attempted to restart the engine by switching boost pumps, selecting different fuel tanks, and activating the emergency header tank pump, but the restart was unsuccessful. He declared an emergency and intended to return to PIR. Another restart attempt involved setting fuel to cutoff, boost pump on, igniters to AUTO, generator off, and starter on. At that time, Ng was about 15%, the fuel condition lever was advanced, and a “pop” was heard with a puff of smoke from the right exhaust. Engine torque did not increase, so the pilot closed the fuel condition lever. The pilot reported not using the manual override fuel switch during the descent.
While maneuvering back toward PIR, the airplane also lost electrical power, resulting in loss of the primary flight display, both GPS displays, and the annunciator panel. The pilot became disoriented during the descent to the airport. Realizing he could not reach PIR, he attempted a forced landing to bluffs and rolling terrain. The airplane impacted the terrain, came to rest upright, and sustained substantial damage to the fuselage and both wings.
After the accident, the pilot observed that the passenger, seated in a rear forward-facing seat, was barely conscious. After checking vital signs, the pilot performed cardiopulmonary resuscitation until first responders arrived.
Postaccident examination at the site revealed no preimpact external anomalies or malfunctions. The airplane was retained for further examination.
Aircraft Information
A review of the airplane’s maintenance records showed that in 2003, the airplane was modified to a JetProp DLX per a supplemental type certificate, which included installation of a Pratt & Whitney Canada (PWC) PT6A-35 turboprop engine. The pilot reported purchasing the airplane in 2014.
On August 22, 2023, an airframe logbook entry indicated installation of a Garmin G500TXi system and other avionics, and removal of an Aspen Avionics primary and multifunction flight display system. According to the pilot, due to delays in available avionics components, the airplane was out of service for about 1 year and 4 months. According to the HOBBS indicator, at the time of the accident the airplane had accumulated about 11 hours since the avionics installation.
Wreckage and Impact Information
Examination of the airframe revealed that the cockpit battery display indicated 24.7 volts, the fuel selector was in the right tank position, the fuel transfer pump switch was in the manual position, and the emergency fuel transfer switch was off. The header tank contained about 2.4 gallons of fuel consistent with Jet A. The fuel line between the oil/fuel heater and the engine fuel pump was opened, and no fuel drained. The airframe fuel filter and bowl contained about 1 pint of clear fuel. The airframe fuel system components—including the right-wing fuel transfer pump, fuel selector valve, emergency transfer pump, header tank boost pumps Nos. 1 and 2, header tank float switch, header tank pressure transducer, firewall shutoff valve, and annunciator panel lights—were tested and no anomalies were found. Fuel lines from the wings to the engine fuel pump were clear of obstructions when blown with compressed air.
The left-wing fuel transfer pump wiring was damaged during recovery; the pump was removed for further examination and bench tested at Piper Aircraft, Inc., Vero Beach, Florida, with no anomalies noted.
All four propeller blades were bent aft and secure in the hub. The blades were in the low pitch position with minor cambered face scratching.
The engine was removed and shipped to PWC for functional testing. After installation in a test cell and servicing with oil, the engine underwent dry motoring, engine start, warm-up at ground idle, normal acceleration and deceleration, and shutdown. A second start included engine handling tests, slam acceleration, and slam deceleration. According to PWC, during both runs the engine performance and behavior were within specifications with no limits exceeded.
The Garmin G500 TXi primary flight display was sent to the NTSB Recorders Laboratory for data extraction. Data showed that about 7 minutes after takeoff, the engine experienced a loss of fuel flow, engine torque, and Ng, consistent with the reported power loss. Before takeoff, the header tank fuel quantity indicated 10.8 gallons. During flight, header tank fuel quantity decreased to 5.7 gallons until the power loss. About 1 minute after power loss, the header tank quantity began to increase, reaching 11.1 gallons about 4 minutes later, where it remained until impact.
Additional Information
The JetProp DLX Pilot’s Operating Handbook includes emergency procedures for engine power loss and air starts, as well as manual override operation and loss of fuel flow procedures. The fuel system description indicates that the header tank supplies all fuel to the engine, with automatic or manual transfer from wing tanks. The header tank contains two internal boost pumps; the header tank must be kept full. Normal fuel system management involves monitoring fuel flow, pressure, and header tank level.
Medical and Pathological Information
An autopsy was not performed on the passenger.