Accident Overview
On January 5, 2020, at about 1243 central standard time, an experimental, amateur-built Vans RV-6, registration N420PW, was destroyed in an accident near Cullman, Alabama. The private pilot and passenger sustained fatal injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Witness Accounts
Airport surveillance video showed the pilot and passenger arriving around 1230. At 1240, the airplane was observed on the taxiway, where it stopped briefly before proceeding to the active runway. At 1242, the airplane began climbing from runway 02, after which the video ceased recording. Multiple witnesses reported that during the initial climb, when the airplane reached about 350 feet above ground level, a loud "pop" was heard. The airplane then entered an immediate sharp left banking turn, appearing to attempt a return to the airport. Witnesses stated the airplane stalled and entered a left spiral downward turn, completing two rotations before colliding with terrain on airport property adjacent to a taxiway. Other witnesses described similar events, including a popping noise and a loss of engine power preceding the steep turn back toward the runway.
Aircraft Information
The Vans RV-6, N420PW, was an experimental, amateur-built airplane. Its most recent condition inspection was completed in 2014, according to maintenance records. The co-owner reported that the pilot had flown the airplane from Cullman Regional Airport (CMD) to Auburn University Regional Airport (AUO) around December 31, 2019. On the return flight, the pilot diverted to Hartselle/Morgan County Regional Airport (5M0) due to wind conditions at CMD. The total trip distance was estimated at 260 nautical miles. The co-owner did not know when the airplane was returned to CMD or if it flew between that trip and the accident. Fueling records showed the airplane was last fueled on November 29, 2019, with 18.7 gallons of 100LL aviation fuel.
Wreckage Examination
The airplane impacted terrain approximately 1,500 feet from the departure end of runway 02. All flight control surfaces were found at the accident site. The cockpit was crushed to the bulkhead, and the instrument panel sustained impact damage, with no reliable instrument readings. There was no post-crash fire. Although the fuel tanks were breached, no residual fuel was observed at the site. Examination of the fuel selector revealed it was positioned between the left and right tank settings. When the selector was in this intermediate position, fuel was supplied only from the left tank, as determined by pressurized air tests. The selector functioned correctly in the left and right positions. The engine crankcase was intact with impact damage but no fractures indicating catastrophic internal failure. The carburetor float bowl was about half full of blue liquid with an odor consistent with aviation gasoline; a water test showed no water. The fuel floats and needle/seat assembly were undamaged. The engine-driven fuel pump produced air when actuated by hand and contained liquid with an aviation gasoline odor; no internal damage was noted. However, when the fluid lines from the airframe to the pump and from the pump to the carburetor were removed, no liquid drained from them. Cylinder examination via borescope showed normal operating signatures and combustion deposits. All cylinders exhibited thumb compression and suction, and rocker arms and valves moved correctly. Both magnetos produced spark on all terminals. The two-blade constant-speed propeller was separated from the flange, with both blades showing "S"-type bending and chordwise scratching; one blade had aft bending and twisting deformation.
Medical and Pathological Information
An autopsy performed by the University of Alabama's Department of Pathology determined the cause of death as multiple blunt force trauma, with the manner of death accidental. No significant natural disease was identified. Toxicology testing by the Alabama Department of Forensic Sciences identified benzoylecgonine in cavity blood. FAA Forensic Sciences Laboratory testing found cocaine in urine but not in blood; its inactive metabolites benzoylecgonine and ecgonine methyl ester were present in blood and urine. While no delta-9-tetrahydrocannabinol (THC) was found in blood or urine, its active metabolite 11-hydroxy-delta-9-THC was found only in urine at 2.6 ng/ml, and its inactive metabolite carboxy-delta-9-THC was found in blood at 1.5 ng/ml and urine at 15.2 ng/ml.