The preliminary investigation conducted by the National Transportation Safety Board suggests that challenging wind conditions played a significant role in the plane crash near Shaktoolik on June 16 that resulted in the deaths of the pilot, Jim Tweto, and a passenger.
The ill-fated flight of the Cessna 180H aircraft operated by Golden Eagle Outfitters, Inc. crashed, was being conducted in support of a remote bear hunting excursion.
Jim Tweto, an experienced bush pilot renown throughout Alaska’s aviation community, had departed earlier with two hunters and informed the waiting guides that he would return to pick them up after dropping off the clients. However, upon his return to the remote off-airport mountain ridgeline airstrip, wind conditions changed.
According to a witness, the wind conditions were unstable, with gusts intensifying during the hour-long wait for the pilot’s return. The witness, who had flown with Tweto on numerous occasions, described the gusting winds as a factor that had increased throughout the duration of their stay at the airstrip.
The airstrip, situated atop a downward-sloping, rock and grass-covered ridgeline, had a length of approximately 750 feet. Normal departures involved landing uphill on a 060° heading and departing downhill on a 240° heading. Previous departures saw the aircraft temporarily disappearing below the airstrip after takeoff, only to reappear and climb out of the valley.
As the witness observed the initial portion of the downhill takeoff roll, nothing appeared out of the ordinary. However, when the engine noise and the sight of the climbing aircraft failed to materialize, the witness rushed to the ridgeline’s edge. They discovered that the aircraft had impacted the tundra 300 feet below the airstrip. The witness promptly sent an SOS alert and descended to the crash site to search for survivors.
A helicopter pilot, responding to the accident site approximately 45 minutes later, noted that the wind conditions on the day of the crash were “unusual.” The winds varied, gusting from the north at speeds of 10 to 12 knots, calming briefly, then shifting to gusts of 5 knots from the south, only to repeat the pattern.
NTSB investigation of the airstrip uncovered a small cluster of trees positioned about two-thirds of the distance from the departure end on the left side of the runway, in a downslope direction. One of the trees, measuring approximately 12 feet in height and four inches in diameter, had fractured about four feet from its base. The separated portion of the tree was found adjacent to the trunk, displaying fragments of red paint that matched the color of the accident airplane.
Detailed examination of the wreckage revealed that the aircraft impacted the tundra in a steep nose-down and wings-level attitude approximately 1,200 feet from the broken tree. The impact displaced the wings, with the leading edge of the right wing uniformly crushed aft along its span. Both the upper and lower wing skins exhibited compression damage. Flight control continuity was established despite several breaks and separations, which were consistent with impact and overstress failure.
The engine was separated from the airframe and came to rest inverted behind the left wing. The propeller hub was fractured, and the propeller blades were separated from the hub. Interestingly, the right horizontal stabilizer and elevator did not display leading-edge impact signatures, and the elevator remained attached. In contrast, the left horizontal stabilizer showed a concave dent perpendicular to the leading edge, approximately one foot outboard of the stabilizer root. Tree sap and embedded tree fibers were also observed in the leading edge of the horizontal stabilizer.
While the investigation into the exact cause of the crash is still ongoing, the NTSB’s preliminary findings indicate that the challenging wind conditions, characterized by gusting and unpredictable shifts, likely contributed to the accident. The presence of the fractured tree, coupled with the observed tree sap and fibers on the stabilizer, suggests a possible interaction between the aircraft and the trees during takeoff.
