NTSB initial report shows ‘unusual wind’ event was factor in deadly Shaktoolik Cessna crash last month

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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.

22 COMMENTS

  1. That’s too bad. Could have possibly been a downdraft or microburst situation although those wind speeds aren’t anything that’s too unusual in the bush. If the pilot was surprised however and this happened during takeoff and landing, the result is evident. I can remember landing in dillingham with a pilot that probably has more hours than Tweeto. We hit some sort of weird anomaly wind on final and we’re about 20 feet off the ground when suddenly we found ourselves to the extreme left of the runway. The pilot instinctively reached for a throttle and went full power and got to straighten out and back up onto the center of the runway and landed it. Dillingham is a concrete runway capable of landing Air Force One so the distance that we were blown off course was significant. It’s a risky business out there and if you fly long enough, strange things happen. Thanks John.

    • Forkner, crosswind conditions aren’t a weird anomaly! And I’m sure that the pilot not only used power but also made cross control corrections to get the plane centered and lined back up with the runway. And if you were flying with “Jackie” Smeaton you flew with one of the best bush pilots. And all though he was lucky enough to live through his flying career, his career was not without accident: the same could be said for Ball, Krause, the Tibbetts’s, the Kings, the Christiansen brothers, and Orin Seybert–all exceptional pilots on the Alaska Peninsula and in and around Southwest Alaska. None of them would have said–or in Orin’s case, since he is still kicking, would say–that crosswind conditions were anomalous! That said, I’m glad that you lived through your “strange encounter!”

      Incidentally, Dillingham doesn’t have a concrete runway!

      • Oh yes it does. How long since you were there? 75 years. It was weird because it was dead calm on final. A twin engine Navajo land in front of us. Might have been some turbulent air off him. I have flown with some of them including one of Orins boys.my pilot that is also certified to fly 737s wasn’t on your list.

        • Now you’ve got us all laughing, Gregory! You can get by b.s.ing for only so long! I must say though that you have all the “credentials” to run for public office! Hell, you’re so glib, I might even volunteer to go door-to-door for you as a spoof on the whole political system!

          • Google maps shows around a 7,000′ (including overruns) asphalt strip just W of Dillingham. Dirt roads connecting it show dirt on the asphalt. Ramp / tarmac appears to be asphalt also. Cheers –

          • Knowing what I know now I indeed would run if I was 30 years younger. I’d win too with or without your support. No need to get your panties in a wad. I lived and flew in the bush for 25 years and picked up a thing or two. Put some salve on that butt and it’ll be okay.

          • Gregory, you brought such levity that it is incumbent upon me to edit the caption of my reply to you: “This is Lucifer himself, and I ain’t had such a good laugh in a long time!”

            And to think that Milton–the old timer–missed all the humor and joy in hell!

  2. Taking off with a tail wind can be problematic. And once airborne a significant gust of wind in the same direction can reduce the margin between flying and stalling the airplane because it suddenly reduces the wind coming over the wings which is needed to create lift. It could happen just after liftoff which generally involves a smaller margin between flying and stalling the plane. That is my guess what happened.
    Unpredictable or “ unusual “ winds are often encountered by pilots flying in remote Alaska. They should be a consideration at all times when deciding whether it is safe to operate the plane. A down wind take off in a relatively loaded plane on a short gravel/ dirt landing strip carries its own risks. Add gusty or unusual winds and the risk increases.
    Tweto was considered to be a very good pilot. But he is not the first very good pilot to get killed flying in remote Alaska bush flying. And when the FAA or NTSB comes up with the “ probable cause” of the accident, it will in all likelihood say it was the failure of the pilot to maintain flying speed during a take off on a short remote dirt strip with a tail wind. Some mention may be made of the weight of the airplane and of unusual gusty conditions. Regardless, and regrettably for most everyone, the probable cause will be still be distilled down to “Pilot Error”.

    • I wouldn’t so “windy” or presumptuous, Alaskans First. Who knows what was happening behind the yoke: it’s not as if pilots are immune from strokes or heart attacks!

      • Lucifer,
        you might want to read what I wrote more carefully I was careful to say that “in all likelihood” the FAA or NTSB will attribute the accident to the pilots failure to maintain flying speed. That is not “presumptuous” or “windy”. It is a simple opinion based on what is presently known. And it does not preclude other contributing causes. When is the last time you read that “probable cause” for an aircraft accident in Alaska resulting in fatalities was caused by the pilot having a stroke or heart attack? And my use of the term “probable cause” is often used by the NTSB because there might be the possibility that there were other unknown factors that might have contributed to an accident.

        • As you wrote, “Regardless, and regrettably for most everyone, the probable cause will be still be distilled down to ‘Pilot Error’.” “Probable cause” may be a NTSB term of art, but “pilot error” is a loaded term–I don’t give a damn how you spin it!

          • Lucifer, you need to take a deep breath. Reasonable may disagree but does that justify your rant?
            I agree with you. Pilot error is indeed a loaded term. Probably because it has resulted in many unnecessary deaths. Your support of our bush pilots is good. They serve us well. But they make mistakes and this “ looks” like one of them. Why is so hard for you to understand that probability.

    • It’s easy to say that he should have taken off from the other direction, but we don’t know all of the circumstances at the time. Another question :
      I see no trees in the MRAK photo. How could he hit the only tree near the runway?

  3. What a loss for the family and western Alaska. Looking at the photo he hit hard. Too bad Jim didn’t have a 185, the extra 70 HP may have made the difference in this case but who knows, it’s just tragic

  4. Talk about Federal overreach! Here’s Outside investigators using my taxes to ask questions of the local citizens and use “science” (and not faith)! So they’ll make a report with recommendations for higher safety that they will impose on State of Alaska Bush pilots!/s

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