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BleuCiel

Finally! The terminal velocity of a cat!

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Old story, but perhaps of interest here. Heard it on NPR radio today.

On Landing Like a Cat: It Is a Fact

EVERY year, scores of cats fall from open windows in New York City. From June 4 through Nov. 4, 1984, for instance, 132 such victims were admitted to the Animal Medical Center on 62d Street in Manhattan.

Most of the cats landed on concrete. Most survived. Experts believe they were able to do so because of the laws of physics, superior balance and what might be called the flying-squirrel tactic.

In a study for the medical center, Dr. Wayne Whitney and Dr. Cheryl Mehlhaff recorded the distance of the fall for 129 of the 132 cats. The falls ranged from 2 to 32 stories.

Even more surprising, the longer the fall, the greater the chance of survival. Only one of 22 cats that plunged from above 7 stories died, and there was only one fracture among the 13 that fell more than 9 stories.

Why did cats from higher floors fare better than those on lower ones?

One explanation is that the speed of the fall does not increase beyond a certain point. This point, ''terminal velocity,'' is reached relatively quickly in the case of cats. Terminal velocity for a cat is 60 miles per hour.

Until a cat reaches terminal velocity, the two speculated, the cat reacts to acceleration by reflexively extending its legs, making it more prone to injury. But after terminal velocity is reached, they said, the cat might relax and stretch its legs out like a flying squirrel, increasing air resistance and helping to distribute the impact more evenly.


Link http://www.nytimes.com/1989/08/22/science/on-landing-like-a-cat-it-is-a-fact.html

Tried to find the paper in the medical journal, but their online offerings don't go back that far.

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Uh...how was the terminal velocity of "a cat" determined?
Might a fat and heavy one fall faster than a skinny one?

Unless it is explained, how a "cat" (all cats) have the same descent rate, and how the 60 mph terminal velocity figure was determined, the article is just a bunch of speculative bullshit, pretending to be something else.

And, I even wonder if any living thing can reach terminal velocity in such a short distance. Humans can't reach terminal velocity in fewer than about 12 seconds. Can a cat?

Bunch of silliness.

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dpreguy

Uh...how was the terminal velocity of "a cat" determined?
Might a fat and heavy one fall faster than a skinny one?

Unless it is explained, how a "cat" (all cats) have the same descent rate, and how the 60 mph terminal velocity figure was determined, the article is just a bunch of speculative bullshit, pretending to be something else.

And, I even wonder if any living thing can reach terminal velocity in such a short distance. Humans can't reach terminal velocity in fewer than about 12 seconds. Can a cat?

Bunch of silliness.



Well theoretically if the terminal velocity of a cat is 60 mph, and a human's is approximately 120, when you account for the fact that acceleration is constant then a cat will reach terminal velocity much faster than a human. It would take approximately half the time for a cat to reach terminal so yes....yes they probably can.
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dpreguy

Unless it is explained, how a "cat" (all cats) have the same descent rate, and how the 60 mph terminal velocity figure was determined, the article is just a bunch of speculative bullshit, pretending to be something else.

And, I even wonder if any living thing can reach terminal velocity in such a short distance. Humans can't reach terminal velocity in fewer than about 12 seconds. Can a cat?
Bunch of silliness.



Think of a feather and express the time needed for it to reach terminal velocity in milliseconds.
Than reread your post.
What goes around, comes later.

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The thing they highlighted on the NPR radio show was this:

Cats that fell 5 stories or less were rarely hurt.
Cats that fell from 5 stories to 9 stories were often hurt.
Cats that fell from over 9 stories, were rarely hurt.

So why is it that the over-9 story falls had a low injury rate just like the much lower falls? It's the opposite of what you would expect.

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That article is from 1989, so it is outdated.
With an average lifespan of 12 years, all the belly-flying cats of that generation are long gone.

The current generation of cats are doing head-down, and/or sitflying, (while wearing GoPros), so their terminal velocity is significantly higher.
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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ryoder

...The current generation of cats are doing head-down, and/or sitflying, (while wearing GoPros), so their terminal velocity is significantly higher.



Which makes the Cat-Chasing Championships much more challenging.
"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

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muff528

I'm getting about 58 mph at sea level, or ~100 mph for V(t) at 10000 ft. for a ~11 lb. tabby, falling in a reasonably stable, modified frog ...depending on how much fur is flapping.



“… and fold up and do a toggle and jettison and always watch the horizon.”

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Although I'm going a little off topic, cats have also been taken up in a T-33 military jet trainer to test their orientation and righting capability in low or zero-g. The attached photo is from a 1957 aerospace medicine journal.

The results weren't actually too exciting and would take some explanation. Basically, adult cats with a developed righting reflex (unlike the kittens they also took up!) would tend to try to flip over if released upside down despite being in zero G, whether hooded or eyes open. Cats aren't generally big on being upside down. But after repeated zero G parabolas, they would get used to it and just float. Or they would right themselves once G's started to applied even a tiny bit at the bottom of the parabolic arc.


Thankfully we had brave men like this in the United States Air Force (plus ex-Nazi era scientists) to make sure the godless Commies did not take the lead in feline righting reflex science.

Reference:
The Labyrinthine Posture Reflex (Righting
Reflex) in the Cat during Weightlessness
BY SIEGFRIED J . GERATHEWOHL PHD, AND
MAJOR HERBERT T. STALLINGS, USAF,
Journal of Aviation Medicine, Aug 1957

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Travman

I know Dr Karl, a famous Australian radio scientist wrote about this many years ago.
Found a youtube video on it.
https://www.youtube.com/watch?v=kwtKNMAYRag



That was actually pretty good. The closed-caption translation was a little rough, but close enough that you get the ideas.

So why is it that our instructors always told us to tense up our leg muscles to brace for impact for a PLF landing? From this story, it looks like having relaxed muscles would be a better way to land and avoid injury...

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BleuCiel

***I know Dr Karl, a famous Australian radio scientist wrote about this many years ago.
Found a youtube video on it.
https://www.youtube.com/watch?v=kwtKNMAYRag



That was actually pretty good. The closed-caption translation was a little rough, but close enough that you get the ideas.

So why is it that our instructors always told us to tense up our leg muscles to brace for impact for a PLF landing? From this story, it looks like having relaxed muscles would be a better way to land and avoid injury...

What you should have been told was to bend your knees and absorb the initial energy in your leg muscles as you continue through the PLF/R.

Relaxing your legs too much will result in an injury.
Nobody has time to listen; because they're desperately chasing the need of being heard.

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mcordell

***Uh...how was the terminal velocity of "a cat" determined?
Might a fat and heavy one fall faster than a skinny one?

Unless it is explained, how a "cat" (all cats) have the same descent rate, and how the 60 mph terminal velocity figure was determined, the article is just a bunch of speculative bullshit, pretending to be something else.

And, I even wonder if any living thing can reach terminal velocity in such a short distance. Humans can't reach terminal velocity in fewer than about 12 seconds. Can a cat?

Bunch of silliness.



Well theoretically if the terminal velocity of a cat is 60 mph, and a human's is approximately 120, when you account for the fact that acceleration is constant then a cat will reach terminal velocity much faster than a human. It would take approximately half the time for a cat to reach terminal so yes....yes they probably can.

I would think that some of the less social cats might prefer a head down position, and then they could keep up with a belly flying human.

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BIGUN

******I know Dr Karl, a famous Australian radio scientist wrote about this many years ago.
Found a youtube video on it.
https://www.youtube.com/watch?v=kwtKNMAYRag



That was actually pretty good. The closed-caption translation was a little rough, but close enough that you get the ideas.

So why is it that our instructors always told us to tense up our leg muscles to brace for impact for a PLF landing? From this story, it looks like having relaxed muscles would be a better way to land and avoid injury...

What you should have been told was to bend your knees and absorb the initial energy in your leg muscles as you continue through the PLF/R.

Relaxing your legs too much will result in an injury.

Right, but with your knees bent slightly, you tense your leg muscles in expectation of the impact. You don't just let your legs hang limp. Yet, this seems contrary to what they're saying these high-falling cats do.

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headoverheels


This one wasn't high enough to reach terminal, but has pretty good form:

https://www.youtube.com/watch?v=2cjwiElAvyw


Title of the video should be base jumping, not skydiving cat.



It's much better with a soundtrack: https://www.youtube.com/watch?v=Veg63B8ofnQB|
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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I get that an object with a lower terminal velocity will reach that terminal velocity faster than a higher one. Duh.

You are assuming you know the terminal velocity of a falling cat.

Reread your own post. And, while you are at it, reread mine and see if you can figure out why you missed the point.

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ryoder

***
This one wasn't high enough to reach terminal, but has pretty good form:

https://www.youtube.com/watch?v=2cjwiElAvyw


Title of the video should be base jumping, not skydiving cat.



It's much better with a soundtrack: https://www.youtube.com/watch?v=Veg63B8ofnQB|

I always thought it would have been better if someone had done that with the soundtrack to say "FAIL!" :ph34r:
lisa
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You should not play with cat that way since they are family pets. If you are really curious about why a cat lands on his legs, don't come on this forum but see studies about cat on Internet.
Be more considerate for cats and animals in general. After all cats have save millions of persons from starvation by eliminating mice from the cereal warehouse. They are still used on boats transporting cereals.
Learn from others mistakes, you will never live long enough to make them all.

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