NTSB Cites Failure To Remove Control Lock In Snodgrass Crash

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The NTSB has cited the pilot’s failure to remove the flight control lock as the probable cause of the crash of a SIAI-Marchetti SM-1019B that killed respected airshow performer and retired naval aviator Dale “Snort” Snodgrass in July 2021. In its final report, which was published on Wednesday, the Board noted that “the control lock and its retaining clip were essentially undamaged, and the lock was found raised off the floor,” indicating that it was engaged at the time of the crash. Investigators also reviewed high-resolution footage from airport security cameras and determined that “deflections of the elevator and ailerons were either zero, or so small that they could not be seen.”

“The pilot was reported to be extremely thorough about performing preflight checks, and according to his wife, the expected duration of his normal preflight activities would not have allowed him to depart when he did,” the NTSB wrote in its report. “The pilot had limited experience in the accident airplane, which could explain why he did not remove the control lock during the preflight inspection. There was no video evidence to provide insight into the duration and scope of the pilot’s preflight inspection; however, omission of the preflight control check was uncharacteristic given his extensive flight experience, and the reason it was not performed could not be determined.”

As previously reported by AVweb, the accident occurred shortly after takeoff from Idaho’s Lewiston-Nez Perce County Airport (LWS) on July 24, 2021, at about 11:52 a.m. local time. Investigators found no evidence of any pre-accident mechanical malfunctions or failures and no indication that the pilot’s seat had moved. Toxicology tests were negative and it was noted that pilot incapacitation was unlikely given that Snodgrass’ final radio transmission “showed that he was aware and speaking after the onset of loss of control.”

Snodgrass had purchased the accident aircraft in April 2021 and it was delivered to him the following June. He had an estimated 20 hours in the aircraft prior to the crash. Snodgrass, who was an F-14 demo pilot for U.S. Navy for more than ten years, had logged around 6,500 hours of civilian flight time.

Kate O’Connor works as AVweb's Editor-in-Chief. She is a private pilot, certificated aircraft dispatcher, and graduate of Embry-Riddle Aeronautical University.

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19 COMMENTS

  1. Tragic.
    One comment: if you have a jammed horizontal stabilizer and the control has a tab as opposed to a spring trim the trim operates in the opposite sense to that if the control is free. Same applies to aircraft like Cherokees and our BD-4 with all moving stabs.
    Design comment: Please designers, don’t ever put internal control locks in an aircraft that still enable you to get into the seat or even operate ANY of the controls.
    Most airplanes are enough of an ergonomic slum as it is.
    Mike

  2. Sad.

    IIRC, a Pacific Western Airlines DC-3 crashed because external control locks were not removed.

    IIRC there was an alert or AD on the twin Convairs like the CV640. (RR Dart conversion of CV340/440, CV580 similar, CV600 similar. conversion of CV240).

  3. And yet even in my 1959 C-172A, the yoke control lock blocks the starter. This isn’t rocket- (or even aero-)science, nor even a new concept.

    One wonders if Siai Marchetti doesn’t shoulder a significant liability exposure for this design.

  4. Putting SMS into action:

    Add to “Shut Down” check list “Do POST Flight Checklist”.
    Add to “Post Flight”: “Write Down any Squawks”(while still fresh in your mind) and “Clip Pre-Flight Check List to Oil Door”.

  5. “Read the checklist” it clearly states “remove control lock”. Read the checklist it clearly states, “flight controls free in movement”. So While it is a design obviously that could use some updates it is still up to us pilots to follow through on safety. I too have done stupid things “like no reading the checklist thoroughly and thank God it was not catastrophic, only annoying.

  6. This is one crash where a fire extinguisher ball mounted forward of the fire wall, might have saved his life. It looked like it took forever for someone to respond… and then it began to burn. These ball fire extinguishers are designed to only activate if hit by flame, not heat. They only weigh 1.5 lbs…. Seems like a small investment to not burn alive…

    • The balls are set off by heat, not flame. The flame, of course, provides the heat.

      But what else sets them off? How well do they handle vibration? Or rough landings? And are ANY certified for use in a plane? What happens if it pops when you’re in cruise mode – will your engine be happy ingesting fire extinguishing dust?

      And what happens during the crash? The G forces should be enough to set it off, even before the post accident fire is starting. Your firewall directs the powder dispersal forward of the plane, while your wing tanks are pouring fuel out behind – probably not a good outcome.

      These look to be potentially useful for stable, static installations where the self-activation could be useful. But quite worthless for active fire fighting, as compared to regular, directable extinguishers.

  7. Hey – I’m NO expert and I’m not out to Monday morning quarterback this (so I promptly am….. Hmm) It did strike me – how could you NOT notice the controls were locked when taxiing a tailwheel plane. If only for “stick in pit of stomach to keep the little wheel at the back on the ground”.

    So a sorta – “Contributing Factor” – Lack of Wind (at least according to the weather information in the report).

    If there had been any wind and so a requirement to fly the plane on the ground it would have been immediately apparent the controls were locked.

    But in any case – the stick should have been full back. No?

    Well – RIP