[mmcconnell1618]

Over at http://pprune.org the suggestion is that the pilot's seat was not locked into position correctly and slid back during takeoff. This caused the pilot to pull back on the stick too early and his instinct was the push forward to keep the plane on the correct trajectory. He likely over-corrected and ended up flying 6ft off the ground at the end of the runway where the landing gear caught an antenna and the chainlink fence on top of the brick wall.

It's all speculation at this point.

[cjbprime]

Ugh, there have been Cessna deaths caused the same way. It's my least favorite failure mode to think about, since there's no obvious way to correct. In a Cessna, best you can do is release the yoke and tiptoe on to the rudders, but professional instructors have still died when this happens to them, since low altitude errors are often not correctable by the time you've lost too much altitude.

Usually there ought to be more than one locking mechanism involved, though..?

https://generalaviationnews.com/2018/03/16/failure-secure-se...

https://generalaviationnews.com/2016/10/18/seat-sliding-back...

[userbinator]

In contrast, I can't say I've ever heard of seats in cars having this problem. Is it because plane seats are highly optimised for weight?

[FabHK]

Suppose your car seat hasn’t locked. You drive, then you suddenly go up a hill, and the seat slides back. Well, fine, you hold on to the steering wheel (or not), stop, take a breath, adjust the seat, and carry on.

Suppose your plane seat hasn’t locked. You taxi around to the runway (slow and always level), then you begin the takeoff run. Already, you have some acceleration pulling back. Then you gently pull back the yoke to rotate. Now, suddenly your seat slides back. You hold onto the yoke, stall, and die. Or you let go off the yoke, and now the plane is unpiloted in the crucial take-off phase. And, note, stopping is not an option at this point.

That’s why vigorously thrashing around in your seat is part of the before-takeoff checklist (“Seat - LOCKED”).

[radicalbyte]

My wife knows of two fatal car accidents caused by this. Don't adjust your seat whilst driving peeps, and make sure it clicked into position before you drive if you adjust it.

[sizzle]

Mind sharing what causes the accident, does a sliding seat cause the driver to yank the steering wheel and lose control?

Also, what about adjusting the steering wheel while driving? Sounds like a similar threat.

[cjbprime]

Wow, thanks for the info. If you happen to have links for them, I'd be curious to read more.

[kozak]

Inability to apply enough force to the brake pedal at the right moment.

[radicalbyte]

One of them was adjusting the seat whilst driving, it flew back and she swerved. The other one I understand was a seat which wasn't clicked in.

[crwalker]

Pulling back on a car’s steering wheel doesn’t do anything. Also, cars have a very low stall speed.

[mcguire]

A car's stall speed depends heavily on the car's altitude.

[cjbprime]

Could be because people don't generally drive 40 year old cars! The aircraft in the first fatal link above was manufactured in 1979 and the seat failed in 2016; the second was manufactured in 1969 and crashed in 2014.

And because it would be less likely fatal in the car, so you'd be less likely to hear of it happening.

(Less likely fatal because car collisions are less fatal due to e.g. airbags, and less likely to impact terrain since it only takes a second to undo your car seatbelt, and because there's no pitch control to have messed up.)

[MaulingMonkey]

My front driver's seat adjustment is all motorized - but not the passenger seat. Originally it annoyed me (the motors are so slow to move!) but now I'm wondering if it might be an intentional safety feature - it's never "unlocked", so you won't suddenly slide away from the pedals and wheel because a part failed to latch right.

[fian]

If your car seat slides back unexpectedly, the most likely problem will be a decreased ability to press down in the accelerator. The seat would generally slide back only under forwards acceleration. Under braking the seat would slide forward giving positive pressure onto the brake pedal.

[GavinMcG]

It also diminishes your ability to brake. And if you do slide back, and the seat then locks in place, that could be serious.

[cjbprime]

You would keep steering the car, while also attempting to unlock the seatbelt. Depending on the car, you could also activate the parking brake. (In my car, it's a button on the center console, and it can be activated at high speed and will provide emergency braking.)

"Serious" is still not the same as "fatal", even if your car hits something. If your plane stalls and falls hundreds of feet, my understanding is that the fatality rate is going to approximate 100%.

[slededit]

If your car seat is electric is probably based on a worm gear which is more or less self locking.

[chopin]

I've flown A380 and B747 on a commercial (Lufthansa) simulator. Both had seats which could be only moved with motors (locking in any position). Don't know how it is with B737 but I would assume the same (for this very reason).

[sundvor]

From that thread:

https://youtu.be/t9Ugn0jq_60

Those passengers just won the lottery.

[mannykannot]

And quite probably many people living just past the end of the runway.