ERA19FA275 · Vans RV 8 Undesignat

The pilot and pilot-rated passenger were conducting a demonstration flight for the passenger, who was interested in purchasing a share of the airplane. Multiple witnesses heard the airplane's engine shortly after takeoff. Two of the witnesses thought that the airplane was performing aerobatics due to variations in engine power sounds. Another witness stated that the airplane’s engine was running smoothly right before he heard it impact terrain. Air traffic control radar information indicated that the airplane was flying about 1,600 ft above ground level shortly before the accident. The last air traffic control radar return, about 11 seconds before the data ended, indicated that the airplane was traveling at a groundspeed of 191 knots. The airplane impacted a wetlands area and was found embedded in 6 ft of mud. The wreckage was heavily fragmented, consistent with a high-speed impact. Examination of the wreckage revealed no anomalies with the airframe or engine that would have precluded normal operation, and damage signatures and witness accounts indicated that the engine was producing power at the time of the accident. The tandem-configuration airplane was equipped with a control stick in the front and back seats; however, the back seat, where the pilot-rated passenger was seated, was not equipped with a throttle control or rudder pedals. According to the builder/co-owner of the airplane, the pilot was known do some low-g aerobatics such as aileron rolls, although he was unsure if the pilot planned to do aerobatics during the accident flight. Toxicology testing of the pilot's kidney and muscle tissue was positive for ethanol. While some or all of the identified ethanol could be from postmortem production, there was not enough information to conclude that with any certainty. However, the levels were well below the regulatory cut off and it was unlikely that effects from ethanol contributed to the events in this accident. The circumstances of the accident are consistent with the pilot’s loss of control and subsequent impact with terrain; however, the reason for the loss of control could not be determined based on the available information.

Verbatim NTSB analysis and probable cause from the NTSB dataset