Beech A36 N8248K accident near Covelo, California

Probable cause

The pilot’s failure to maintain clearance from trees after entering a steep banked turn for unknown reasons. Contributing to the accident was the pilot’s decision to take off toward rising terrain.

NTSB analysis

The pilot and passenger departed from their home in Utah to a coastal airport in Northern California. After a 4 hour and 11-minute flight, the airplane arrived at the intended destination, but did not descend and subsequently turned inland, possibly due to the presence of cloud cover at the destination. The airplane landed and the pilot obtained about 90 gallons of fuel at an airport about 40 nautical miles southeast of the intended destination. The accident occurred during the subsequent departure from runway 28. A witness reported that the airplane lifted off near the end of the 3,670-ft-long runway, clearing trees by about 20 ft before it began a left turn that progressed into a steep turn with an estimated 70-80° bank angle. The witness then noted that, “as it was banking, it started coming lower,” and that when the airplane started to bank, “it lost a lot of altitude from that [the start of the bank] to when it hit the mountain.”

The wreckage was mostly consumed by postcrash fire. Although another witness reported hearing a “popping” sound from the airplane, postaccident examination of the airplane and engine revealed no preimpact mechanical anomalies that would have precluded normal operation. Performance calculations indicated that the airplane would have required a takeoff ground roll distance of about 2,600 ft based on its loading and the atmospheric conditions about the time of the accident. It could not be determined whether the pilot initiated the takeoff from the beginning of the runway and used substantially more runway than that predicted by performance calculations, or if the pilot may have initiated the takeoff from the taxiway intersection nearest the self-service fuel pumps, from which point about 2,400 ft of runway was available.

The airport was surrounded by mountainous terrain. The Federal Aviation Administration chart supplement insufficiently described the topography off the departure end of runway 28, as it failed to include any description of the peaks and valleys immediately off the end of the runway nor did it include the presence of a 4,000 foot-tall mountain peak about 1 nm west of the runway end. A witness stated that most airplanes departing the accident airport used runway 10. The terrain off the departure end of runway 10 comprised mostly open farm fields for several miles.

The reason for the pilot’s steep turn just after takeoff could not be determined based on the available information. It is possible that he may have been maneuvering due to the rising terrain or attempting to return to the runway due to a perceived problem (the “pop” sound noted by a witness). The angle of descent indicated by impact signatures at the accident site was more consistent with a controlled flight into terrain event than that of an aerodynamic stall and loss of control; therefore, it is likely that the pilot failed to maintain clearance from trees while maneuvering after takeoff. A departure from runway 10 instead of runway 28 would have provided the pilot with more favorable terrain clearance and forced landing sites if the pilot had encountered an anomaly during the takeoff.

Text from the NTSB. Open the NTSB docket for WPR24FA018 for the full record.