History of Flight
On December 5, 2021, at 1652, a Piper PA-31-350 Navajo Chieftain (N64BR) was substantially damaged during an accident near Medford, Oregon. The pilot and passenger were fatally injured. The flight was a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot and passenger had flown from Fallon, Nevada, to Medford on November 24. After landing, the pilot observed a large fuel leak from the right wing root. He arranged repairs with a fixed-base operator (FBO) and drove a rental car back to Nevada. On December 4, a mechanic at the FBO notified the pilot that maintenance was completed. The pilot planned to arrive at the airport around 1430 on the day of the accident; he and the passenger arrived about 1600.
The pilot received an IFR clearance with the BRUTE7 departure procedure and LANKS transition. The published SID from runway 14 required a climbing right turn to the MEF NDB, then to the BRUTE intersection. The controller advised the overcast layer base at 200 ft AGL with tops at 2,500 ft. The pilot asked if the controller would call his turn; the controller replied that he should fly the published departure, making a climbing right turn to overfly the approach end of runway 14. That was the pilot's last transmission. The controller then issued a low-altitude alert at 1,700 ft and attempted to contact the pilot without response.
Radar and ADS-B data showed the airplane in the run-up area around 1643, then on runway about 6 minutes later. Departure occurred about 1649:30. After crossing the south end of the runway, it climbed to about 1,550 ft MSL (200 ft AGL), began a gradual right turn, and climbed to 1,950 ft, airspeed 120-130 kts. As the turn continued north, altitude momentarily decreased to 1,650 ft (about 350 ft AGL) with airspeed increasing to 160 kts. The airplane then increased bank angle and made a 360-degree turn, initially climbing to 2,050 ft, then descending to 1,350 ft, consistent with maneuvering below clouds. Airspeed increased to about 160 kts; then it climbed to 2,250 ft with derived airspeed below 15 kts. Six seconds later was the last radar return, about 990 ft north-northwest of the accident site.
Security camera footage showed the airplane descending below the cloud layer, then climbing back up. About 16 seconds later, it descended in a near-vertical attitude. The airplane's position and strobe light appeared illuminated throughout.
Personnel
The pilot previously owned a PA-31-350 and purchased the accident airplane in 2013. His electronic logbooks showed about 1,520 hours in type, with 273 hours in actual IMC. He had departed Medford in August 2018 and 2019 using different departure procedures. In early November 2021, he attended recurrent SIMCOM training, including 2 hours of simulated IMC in the same make and model. During clearance exchange, the pilot requested phonetic readback of the departure procedure; family and associates noted this was normal.
Aircraft
The Piper PA-31-350 Navajo Chieftain (Panther conversion) was manufactured in 1977, powered by two Lycoming TIO-540-J2B engines with four-bladed Q-Tip propellers. It was equipped with a Garmin GNS 530W and autopilot. The last examination was on December 4, 2021, at tachometer 1,754.4 hours. An auxiliary hose assembly was replaced the day before following a leak. The mechanic could not recall the fuel selector position after maintenance. The Pilot Operating Handbook stated that anti-collision lights should not be operating when flying through cloud, fog, or haze due to reflected light causing spatial disorientation.
Meteorological
Video showed the airplane disappearing into a cloud layer and reappearing before the accident. ASOS observations at 1650 reported calm wind, visibility 3 statute miles, mist, overcast at 200 ft, temperature 39°F, dewpoint 39°F, altimeter 30.39 inHg. HRRR model indicated cloud tops near MFR around 2,200 to 2,500 ft MSL.
Wreckage and Impact
The accident site was adjacent to garage bays of an automobile dealership about 2,800 ft west-southwest of the departure end of runway 14. Most wreckage was consumed by fire and had major crush deformation. Unburned cockpit items included current departure procedure plates for Medford. Control continuity could not be fully confirmed due to impact and thermal damage. Propeller blades on both engines showed chordwise scoring, leading edge chips, twisting, and bending consistent with similar rpm operation. Fuel caps were secure. Right wing root fuel system components had impact and thermal damage; the fuel selector valve was positioned to the outboard tank, and the firewall shutoff valve was open. Left wing root fuel system components also showed damage; the fuel selector valve was near the outboard tank, the firewall shutoff valve closed, and the cross-feed valve open. The cockpit fuel selector was thermally damaged with position unknown. It is unknown if these positions existed before impact or why the pilot configured them that way. No preimpact mechanical malfunctions or failures were found.
Additional Information
A Flight Safety Foundation publication described flicker vertigo as an imbalance in brain-cell activity caused by low-frequency flickering of bright light, leading to nausea, dizziness, headache, panic, confusion, and in rare cases seizures and loss of consciousness. It noted that flicker vertigo can also develop from strobe lights or rotating beacons reflected off clouds or water.
Tests and Research
NTSB Performance Division analyzed audio from recorded videos. A performance engineer estimated engine speeds through spectral analysis of sound from a nearby commercial building camera. Estimated engine speed remained consistent within 2,500±100 rpm before the accident, consistent with normal operation. It could not be determined whether the sound originated from both engines at the same speed or from a single engine.