Definite Stall/Spin Accident

[pelmet]

https://twitter.com/aviationbrk/status/ ... 2983203840

[Bede]

Control lock in?

[PilotDAR]

Control lock in?

Certainly a worthy consideration, but if I recall, the control lock on a 150/152 holds the elevator in a lower position than would enable a pitch up like that. Maybe someone with a 150 can comment?

[photofly]

FWIW, I"m not sure it actually stalled. There's no pitch drop or wing drop; it appears mostly to yaw to the left.

Control lock theory: the pilot doesn't deflect the rudder, either, and that's not constrained by the lock on the yoke.

Do 150s suffer from unintended seat roll-back like 172s and 182s? Even then, it doesn't look like there was any elevator deflection.

This is the poster-child control-lock engaged crash:
https://www.1001crash.com/aviation-vide ... gaged.html

[pelmet]

FWIW, I"m not sure it actually stalled. There's no pitch drop or wing drop; it appears mostly to yaw to the left.

Control lock theory: the pilot doesn't deflect the rudder, either, and that's not constrained by the lock on the yoke.

Do 150s suffer from unintended seat roll-back like 172s and 182s? Even then, it doesn't look like there was any elevator deflection.

This is the poster-child control-lock engaged crash:
https://www.1001crash.com/aviation-vide ... gaged.html

I don’t think one could get a better example of a spin entry than this. Both pitch and roll for auto-rotation. The pilot must not have made any rudder input if the rudder did not deflect.

There is not nearly the same room for a 150 seat to move aft as there is in a 172.

[Mooney21]

It appears that he was attempting to land, bounce up and then tried to go around with full flap, which is something the 152 is unable to do. Student pilot became task overloaded imo.

[photofly]

This photograph (Montreal gazette) shows the elevator matching the locked position (as far as I recall):


This one shows the rudder is displaced, but the ailerons still neutral (again, matching the locked position:



In both cases the control system could have been (and looking at the distortion of the tail on impact, probably was) disrupted or displaced by the impact deformation of course.


The Cessna seat-rail AD includes the following text:

Request To Remove Models 150, 152, and 188 From Applicability

Mark Stancy requested we remove Cessna Models 150, 152, and 188 from the airplane Applicability. He thinks the seat travel for those models is too limited to justify this AD even if the locking pin were to slip.

We disagree with this comment. Even a limited seat travel could affect short pilots' ability to reach the controls if the seat slips backwards due to failure of the seat system. This AD action not only requires inspections to prevent seat slippage but also requires inspections to prevent the seat from lifting off the seat track.

We have not changed this final rule AD action based on this comment.

It appears that he was attempting to land, bounce up and then tried to go around with full flap, which is something the 152 is unable to do. Student pilot became task overloaded imo.

Are the flaps fully deflected in the photographs (or video)? It looks like a fairly normal 10° extension to me, not 30° which would be fully extended.

I also don't recall difficulties with a go-around when a student forgets to raise the flaps.

[PT6-114A]

I own a 150. The seat sliding back even a couple of inches at that time could be very alarming to anyone not expecting it. A 150 will do a go around with flaps 40. Max power, lower the nose, get rid of the flaps at least to 20 it will fly away. I don’t think in my plane where the elevator position is held with the control lock in that it would get off the ground. Perhaps with the trim not set correctly at a nose up position?

[PilotDAR]

Are the flaps fully deflected in the photographs (or video)? I don't think so.

I also don't recall difficulties with a go-around when a student forgets to raise the flaps.

I agree with both points. You do have to lower the nose though.....

[photofly]

Worth reminding ourselves that this aircraft is a 152 - lesser maximum flap extension than a 150, and more power.

[Lost in Saigon]

https://aviation-safety.net/wikibase/343072

A3629B8D-4B97-4785-AEC4-24B390ADB1CF.jpeg (310.79 KiB) Viewed 2914 times

[digits_]

Do 150s suffer from unintended seat roll-back like 172s and 182s? Even then, it doesn't look like there was any elevator deflection.

It was a major safety concern at my flying club many years ago. They had some kind of kit installed to help prevent it, but it wasn't bullet proof though.

[photofly]

FWIW, I"m not sure it actually stalled. There's no pitch drop or wing drop; it appears mostly to yaw to the left.

Control lock theory: the pilot doesn't deflect the rudder, either, and that's not constrained by the lock on the yoke.

Do 150s suffer from unintended seat roll-back like 172s and 182s? Even then, it doesn't look like there was any elevator deflection.

This is the poster-child control-lock engaged crash:
https://www.1001crash.com/aviation-vide ... gaged.html

I don’t think one could get a better example of a spin entry than this. Both pitch and roll for auto-rotation. The pilot must not have made any rudder input if the rudder did not deflect.

I took some stills from the video, and overlaid them, to get a sense of the motion of the aircraft:

Screenshot 2023-08-02 at 12.33.24.png (945.79 KiB) Viewed 2899 times

There's some roll at the start of the incident, then it changes mostly to yaw. The empennage slews to the right as the aircraft rotates around its normal axis. You can also see the angle of the vertical stabilizer remains largely vertical through the first part of the manoeuvre, at least until yaw brings the nose level with the horizon:

Screenshot 2023-08-02 at 12.34.59.png (764.66 KiB) Viewed 2899 times

If you took off in a 152 and failed to arrest the left-turning tendency with either rudder or opposite aileron, allowing the nose to yaw controlled to the left, but didn't stall - how would that look any different to what happened here? Just for comparison, there is no rapid wing-drop, which you might well expect on a full power uncoordinated stall.

[JasonE]

I find it disturbing the person who took the video just stands there filming after the crash instead of rushing to help.

[linecrew]

I find it disturbing the person who took the video just stands there filming after the crash instead of rushing to help.

If you watch the video prior to the camera person zooming in, you can see that the accident takes place quite a distance from where they are filming from on the ramp. Also, employees working at a controlled airport have it ingrained in their training that you never, ever run towards the scene of an aircraft accident, especially if it is on, or requires corossing the manoeuvring area. The ARFF, whom are better equipped and trained to handle these situations, will get to the scene before you could anyway. The tower controller would have hit the crash alarm as soon as they saw it happen. I've worked as a rampy at a controlled airport for many years and this is what the non-negotiable rules were for us.

[JasonE]

Good point. I missed it was at Lesage/QC. I thought it was a smaller uncontrolled environment.

[Smurfjet]

A/C was cleared to land on 24.
29 also in operation at the time (nothing implied nor inferred).

[Capt. Underpants]

IMO, this wasn't a takeoff accident, it was a loss of control during a go-around. Not enough forward pressure on the column to counteract the pitch up and flaps left at 30 degrees for too long.

[CpnCrunch]

IMO, this wasn't a takeoff accident, it was a loss of control during a go-around. Not enough forward pressure on the column to counteract the pitch up and flaps left at 30 degrees for too long.

You can definitely see the flaps are down in the video, and it looks like they were near the end of the runway. Perhaps solo, panicked/froze/overwhelmed with the go-around?

[lownslow]

What I can’t wrap my head around is that it was filmed from Gate 34 (you can read it on the ground and the taxiway sign confirms the area) which puts the airplane flying at nearly 90° to runway 24 OR three quarters of a mile to the right of runway 29. Neither one makes a lot of sense.

[rookiepilot]

Can anyone tell where the trim tab is positioned?

A go around with uncorrected nose trim fully up would do this….especially with flaps down.

[photofly]

Can anyone tell where the trim tab is positioned?

A go around with uncorrected nose trim fully up would do this….especially with flaps down.

Doesn't look fully nose-up:

Screenshot 2023-08-02 at 20.26.39.png (1.63 MiB) Viewed 2351 times

[Bede]

^ that's exactly the position of the elevator on the C152 when the control lock is in.

[Bede]

I find it disturbing the person who took the video just stands there filming after the crash instead of rushing to help.

1) what can an untrained bystander do to help, especially if there's ARFF trucks rolling?
2) how would they get out of the terminal building air side?

[photofly]

^ that's exactly the position of the elevator on the C152 when the control lock is in.

Ailerons too. But the control lock is on the yoke and relies on the cable path to the tail maintaining its integrity. It's also a stretch to assume that the control cable path to the elevator wasn't damaged on impact. If you watch the video when the empennage comes down, the rear fuselage is significantly distorted.

But this picture appears to show the ailerons deflected to the right. Look at the tip of the right wing:

Screenshot 2023-08-03 at 07.33.03.png (502.28 KiB) Viewed 2249 times

Curiously I don't see a matching deflection on the left wing. Is it possible there was a defect in the control system?

Also the consensus among the news reports (including the airport operator's twitter account) is that this was a landing accident (go around, or touch and go possibly). If the pilot can fly one takeoff and circuit with the control lock engaged there's no reason why he can't fly a second takeoff.

Maybe someone who speaks aviation french could listen to the liveATC recording?

Given there were no fatalities, do you think the TSB will investigate in any depth?