N90559 - NJ - Glen de Vries accident 11/2021

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Ben E.

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Ben E.
I haven't heard anything about this crash since it happened. I looked up the NTSB report and see that they indicate the probable cause as "The flight instructor’s failure to recover from a steep spiral turn during an instructional flight." The docket linked in the attached report includes a video of the plane spiraling to the ground. The docket makes it sound like they were practicing power off stalls and/or descending spirals. What do you guys think happened and why would the veteran flight instructor not be able to recover?
 

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  • Report_ERA22FA058_104237_5_20_2024 12_48_16 PM.pdf
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Sounds like a power off stall gone wrong?

"airspeed began to decrease due to an engine power reduction from2,400 rpm to 1,300 rpm. The airplane began to pitch nose up, ultimately reaching a maximum pitch attitude of about 37° as the airspeed slowed to 28 knots indicated."
 
It’s just crazy to me that a CFI with 30+ years of experience and an excellent reputation (he was based at my field), couldn’t recover from a spiral or spin from 6000’ AGL. Makes you wonder how lesser CFIs and students survive.
 
maybe the student panicked and was fighting him
 
ConstaP67 said:
maybe the student panicked and was fighting him
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It's possible, but he was a commercial student, so not new to the maneuvers. And the student (Glen de Vries) had recently gone into outer space with William Shatner, so he likely wasn't scared by the maneuvers.
 
On a somber note... @Ben E. , unfortunately, far too often we are left without any definite answers as to the cause of small plane crashes. I recently lost a colleague to such a circumstance.
 
I think a seasoned CFI with a reasonably competent pilot might have let the spin develop for just a little too long until it was unrecoverable.
 
Hengelo said:
I think a seasoned CFI with a reasonably competent pilot might have let the spin develop for just a little too long until it was unrecoverable.
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Bill Kershner (the 'Spin Doctor') taught at his flight school that a spin is a steady state and recoverable regardless of the number of revolutions. We did 20 rotation spin recoveries on the last day of school. It is possible they initiated recovery too low, but above 1000 AGL it should have been no problem in a 172. Maybe they were playing chicken with each other.
 
Hengelo said:
Sounds like a power off stall gone wrong?

"airspeed began to decrease due to an engine power reduction from2,400 rpm to 1,300 rpm. The airplane began to pitch nose up, ultimately reaching a maximum pitch attitude of about 37° as the airspeed slowed to 28 knots indicated."
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The "learner" had flights from the same CFI logged as "steep spiral" practice.

The NTSB seems to compare it to the steep spiral commercial maneuver.

But the description sounds more like a spin.

A spin, especially one in a C172, can easily devolve into a steep spiral, but that's not the same as the steep spiral commercial maneuver. I have no idea why anyone would do one of the former on purpose as that results in very high aerodynamic loads that can exceed design limits.

It's all rather confusing. Did the CFI not understand the difference between the ACS steep spiral maneuver and a spin that turns into a spiral dive? Or the difference between a spiral dive and a spin? Really need a CVR and on-board video to figure this one out. Though interviews with the instructor's past commercial students might be helpful.
 
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dmspilot said:
A spin, especially one in a C172, can easily devolve into a steep spiral, but that's not the same as the steep spiral commercial maneuver. I have no idea why anyone would do one of the former on purpose as that results in very high aerodynamic loads that can exceed design limits.
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Assuming one holds the ailerons and rudder full left with full throttle (spin entry control settings) are you saying that with no changes to this configuration a C172 or C150 can easily devolve into a steep spiral ? If so, how does that develop. Thanks.
 
N444MD said:
Assuming one holds the ailerons and rudder full left with full throttle
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Well, I don't enter spins like that, nor is it that the procedure recommended by Cessna.

N444MD said:
(spin entry control settings) are you saying that with no changes to this configuration a C172 or C150 can easily devolve into a steep spiral ? If so, how does that develop. Thanks.
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This is from the C172 NAV III POH:
"During extended spins of two to three turns or more, the spin will tend to change into a spiral, particularly to the right. This will be
accompanied by an increase in airspeed and gravity loads on the airplane. If this occurs, recovery should be accomplished promptly but smoothly by leveling the wings and recovering from the resulting dive."

The NTSB seems to have gotten distracted here with the fact that the instructor logged "steep spirals" with the student on prior flights. The instructor obviously was referring to the commercial training maneuver "steep spiral", as chandelles, lazy 8s, and power-off 180s were also logged on those flights. But the commercial "steep spiral" training maneuver is a completely different maneuver from a spin-like spiral dive.

Looks like they went up to practice spins on the accident flight, and from the video, it looks like a spin. I guess you don't need to know the difference to work for the NTSB :rolleyes: As to why the pilots didn't recover, no idea.

The brief recovery to a +2,000fpm 30° nose-up climb followed by a second stall/spin makes it sound like a jammed control or one of the pilots having a seizure.
 
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dmspilot said:
Well, I don't enter spins like that, nor is it that the procedure recommended by Cessna.


This is from the C172 NAV III POH:
"During extended spins of two to three turns or more, the spin will tend to change into a spiral, particularly to the right. This will be
accompanied by an increase in airspeed and gravity loads on the airplane. If this occurs, recovery should be accomplished promptly but smoothly by leveling the wings and recovering from the resulting dive."
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The video depicts the airplane in a stable spin to the left. The AP took them to the hard break then someone performed a typical overreaction leading to a new stall. 30s later they crashed. Despite weather reports the video appears to show them break out below a layer. They could have gotten disoriented in the cloud and not realized how quickly they were diving. If they were waiting for a glimpse of the ground they waited too long.
dmspilot said:
The NTSB seems to have gotten distracted here with the fact that the instructor logged "steep spirals" with the student on prior flights. The instructor obviously was referring to the commercial training maneuver "steep spiral", as chandelles, lazy 8s, and power-off 180s were also logged on those flights. But the commercial "steep spiral" training maneuver is a completely different maneuver from a spin-like spiral dive.

Looks like they went up to practice spins on the accident flight, and from the video, it looks like a spin. I guess you don't need to know the difference to work for the NTSB :rolleyes: As to why the pilots didn't recover, no idea.

The brief recovery to a +2,000fpm 30° nose-up climb followed by a second stall/spin makes it sound like a jammed control or one of the pilots having a seizure.
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Interestingly NTSB elected to "redact" (blot out) "steep spiral" in the training invoice in the NTSB packet.

This accident is irksome. I paid the money and spent 3 days looking up at the trees growing larger in the windscreen at Bill Kershner's school in Sewanee in N7557L. The weather conditions were identical. N7557L now hangs in the NAASM in Washington after more than 7000 spins training students. Seeing these guys die this way is humbling. Confidence is always punished in aviation and now I have less.
 
"Confidence is always punished"... that's an interesting phrase I've never heard it before. Curious if you made it up? If so, it's insightful!
 
N444MD said:
The video depicts the airplane in a stable spin to the left. The AP took them to the hard break then someone performed a typical overreaction leading to a new stall. 30s later they crashed. Despite weather reports the video appears to show them break out below a layer. They could have gotten disoriented in the cloud and not realized how quickly they were diving. If they were waiting for a glimpse of the ground they waited too long.
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Autopilot? I didn't see anything in the report about use of an autopilot. The sequence of events leading up to the first spin look very deliberate to me. The altitude, the rapid pitch up, the power reduction, etc.

If we assume that the second stall/spin was not deliberate, which may or may not be a correct assumption, then that would still lead me to believe there was some kind of control problem—either mechanical or stemming from a panic-stricken/seized student. It's hard to attribute this to incompetence for an instructor with 15,000 hours. But it's possible. How many spins had he done? And even experienced instructors have shown some very bad judgment before, like the one that CFITed into the Blue Ridge Mountains.

N444MD said:
Interestingly NTSB elected to "redact" (blot out) "steep spiral" in the training invoice in the NTSB packet.
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I think that's a computer mistake and that they meant to highlight it.

N444MD said:
This accident is irksome. I paid the money and spent 3 days looking up at the trees growing larger in the windscreen at Bill Kershner's school in Sewanee in N7557L. The weather conditions were identical. N7557L now hangs in the NAASM in Washington after more than 7000 spins training students. Seeing these guys die this way is humbling. Confidence is always punished in aviation and now I have less.
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Well, this guy appears to have to been no Kershner. With as many hours as he had, interviews with the instructor's other students could have been insightful. But the investigation here looks subpar.
 
Lndwarrior said:
"Confidence is always punished"... that's an interesting phrase I've never heard it before. Curious if you made it up? If so, it's insightful!
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I did make it up, thank you. My father had a way of detecting the faintest glimpse of pride or self appreciation, and then swiftly stomp it into oblivion. Seems to fit in aviation.
 
N444MD said:
Interestingly NTSB elected to "redact" (blot out) "steep spiral" in the training invoice in the NTSB packet.
Click to expand...
I think that's a computer mistake and that they meant to highlight it.

That could make some sense here. OTOH, the file handle on this document includes "N90559_Redacted-Rel.pdf". "Redacted" meaning "erased". So if they had to testify in court and said actually there was never any "spiral" training, combine that with "non-volatile ram buffering" and the remainder of the report and there is no basis whatsoever to implicate Cessna or Lycoming as possible contributors to the accident. I'm not a conspiracy theorist but this just kinda jumps out at me. Will reexamine after coffee this AM lol. Thanks for contributing.
 
N444MD said:
I did make it up, thank you. My father had a way of detecting the faintest glimpse of pride or self appreciation, and then swiftly stomp it into oblivion. Seems to fit in aviation.
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That's awesome! Though I'm not sure if that's a good thing or a bad thing? Maybe a little of both?
 
Lndwarrior said:
That's awesome! Though I'm not sure if that's a good thing or a bad thing? Maybe a little of both?
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I raised my kids with positive affirmation and encouraged confidence. I hope they turned out better for it. In aviation, OTOH, I'm not sure there is a distinct separation between confidence and complacency. They might even be the same.
 
In my head, a confident person is someone that is absolutely willing to question their choices, because they're 100% comfortable being wrong from time to time.

But a little negativity can be good too, I think. A friend of mine used to describe a certain mindset as "there we were, fat dumb and happy", meaning not arrogant or condescending, just not aware enough of what might be going on that they haven't noticed. So a little bit of trust but verify directed inward is probably good. Maybe not from a happiness perspective, but from a not ending up in a flaming ball of aluminum perspective.

So I guess I do believe there's a difference between complacency and confidence, but it's subtle.
 
GaryM said:
I would say 'overconfidence is always punished.'

The problem is, the overconfident don't realize they are on the wrong side of the line between confidence and overconfidence.
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Where Dunning meets Kruger.
 
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