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Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

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Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#81

Post by tialaramex »

ricksunny wrote: post #70
King-Aaron wrote: post #34

Earlier quoted context omitted.

That introduction Haldane quote: > You can drop a mouse down a thousand-yard mine shaft; and, on arriving at the bottom, it gets a slight shock and walks away, provided that the ground is fairly soft. A rat is killed, a man is broken, a horse splashes. "A horse splashes". That's some mental imagery right there.

Makes me wonder if a bunch of the world's smallest flightless mammal (a fraction of the house mouse's mass) were released at altitude, would they survive? (Not proposing that this be done but thought experiments and/or simulations): https://en.m.wikipedia.org/wiki/Etruscan_shrew

At altitude it's very cold, the shrews don't work well in the cold due to the same thing that makes them suitable for this experiment - they are very small, thus they lose heat to the environment easily. So, it's possible they freeze to death first. But yes, I imagine that if they survive the cold and aren't falling onto a hard surface (e.g. they land in grass, not a car park) they would survive.

For them other than the cold a drop from 1000 metres is the same as a drop from 10 metres.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#82

Post by jodrellblank »

nhkcode wrote: post #36

Finally someone is filling the knowledge gap identified by https://www.ncbi.nlm.nih.gov/pmc/articles/PMC300808/

> “Indeed, in seminal work published in the BMJ in 2003, a systematic search by Smith and Pell for randomized clinical trials evaluating the efficacy of parachutes during gravitational challenge yielded no published studies.1 In part, our study was designed as a response to their call to (broken) arms in order to address this critical knowledge gap.”

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#83

Post by snitty »

amelius wrote: post #57

Did anyone try to use a large airbag suit/chamber to survive a plane crash while still in the plane?

To the best of my knowledge that hasn't been tried. Among other things, fatal crashes typically occur at speeds over 2x those of car crashes. There's no meaningful ability to emergency brake before a crash, and many small airplanes don't have the weight budget to get the things that help you survive a crash, like crumple zones.

An airbag won't do much if you're still going to be squeezed between the engine and tail of the plane at 180 mph.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#84

Post by tialaramex »

mannykannot wrote: post #74
d--b wrote: post #60

Honest question: is this satire or gpt?

It is clear that it is satire, but it does not really work because it asks the wrong question. When you ask the right question (about travelling in an airplane, not jumping out of one) the fact that commercial aviation is conducted without parachutes (though with seat restraints) makes sense.

Surely this work's result is indicative for commercial air travel. The vast, vast majority of passengers will leave the aeroplane when it is stationary and they will drop far less than half a meter when disembarking, circumstances in which the parachute was ineffective. So that's not the wrong question at all.

The ideal satire ought to bring up what we should do, ridiculing it. For example, the famous "A Modest Proposal" says that we shouldn't consider taxing the wealthy, particularly the people who make most money from Ireland while not even living there. It insists you couldn't even begin to tackle the problem with taxation or other measures, whereas eating babies would solve the problem entirely.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#85

Post by galaxyLogic »

londons_explore wrote: post #47
gnicholas wrote: post #31

I came to leave a snarky joke comment about "in mice?", and then I remembered that mice don't actually need parachutes because their terminal velocity is roughly the same as a human using a parachute [1]. If someone actually ran the study with mice, they'd find that parachutes aren't necessary! 1: https://johnmjennings.com/can-a-mouse-survive-a-fall-from-a-...

The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... Just because they don't fall super fast doesn't mean they don't get injured because they don't have as much distance to "drop and roll" like a human does.

> mice don't appear to deliberately jump off high things

It could also be because they don't like to change their location too fast. You never know where you could end up. When you fall you might fall next to a cat for instance.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#86

Post by jonashus »

londons_explore wrote: post #76
411111111111111 wrote: post #69

Earlier quoted context omitted.

> The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... They explicitly added the caveat about the soft ground. There'd be very little opportunity for mouses to become comfortable with jumping from high areas as there'd be very few occasions that satisfy the requirement. If the mouse jumped into a cave and can't get out, it'd starve to dea…

Mice around me fairly frequently climb trees. They know whats at the bottom of the tree (hard soil). Yet I never see them jumping off - they always climb back down the way they came up. It could be to avoid getting disorientated though, or to be able to see a predator and reverse course...

Where I live in northern Europe almost all ground in the forests are soft. There is moss, small plants, grass or leaves everywhere.

I can't imagine why the mice would climb trees, but if they did and fall down, they probably gonna be fine most of the time.

In many forests there is lots of large rocks and steep slope/cliffs/precipice in the range 0-5 m where mice possibly could shorten their path by jumping. But I'd suppose they rather use a path they can go in both directions.

Re: Parachute use to prevent death, trauma when jumping from aircraft (2018) [pdf]

#87

Post by littlestymaar »

londons_explore wrote: post #47
gnicholas wrote: post #31

I came to leave a snarky joke comment about "in mice?", and then I remembered that mice don't actually need parachutes because their terminal velocity is roughly the same as a human using a parachute [1]. If someone actually ran the study with mice, they'd find that parachutes aren't necessary! 1: https://johnmjennings.com/can-a-mouse-survive-a-fall-from-a-...

The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt... Just because they don't fall super fast doesn't mean they don't get injured because they don't have as much distance to "drop and roll" like a human does.

> The fact that mice don't appear to deliberately jump off high things as a way to get down tells me that they probably do get hurt...

It's not how this works, cats are decent swimmers yet they generally refuse to get anywhere close to water…

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