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Assuming a fall from a survivable height, will a cat always land on its feet?

Has this been studied? Is there real data to back it up?

Oddthinking
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Monkey Tuesday
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  • Assuming a sufficiently quick release from height `< cat's legs` I can pretty much guarantee that the cat won't land on it's feet, unless everything I know about gravity is wrong :) – Nicole May 11 '11 at 01:50
  • In all seriousness, what are the experimental boundaries that you would use to define "always"? – Nicole May 11 '11 at 01:53
  • @renesis I've been thinking about that too. However, I just went with the claim worded exactly as I've heard it since childhood. The intangibility of a term like "always" is what makes claims like this hard to analyze, but I can't imagine there's any real way to test this that doesn't involve repeatedly throwing cats from various heights. – Monkey Tuesday May 11 '11 at 01:59
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    A won't land on its feet if it is unconscious. – Chris Dennett May 11 '11 at 02:15
  • I also wonder if a cat was able to enter freefall and reach terminal velocity if their sense of "down" would be lost - but that should be completely within the bounds of this question. – Nicole May 11 '11 at 02:21
  • I recall a study that collected anecdotes from cats falling out of windows. First, the chance for survival *increased* with increasing height because the cat's tail could then be used to turn the cat on its feet. For ever increasing height, however, lethality increased again. – Lagerbaer May 11 '11 at 03:10
  • There is nothing physically impossible about the claim. Many animals use their tails to steer and balance. Squirrels come to mind, as well as the flying squirrel – Lagerbaer May 11 '11 at 03:11
  • cats have the natural ability (reflex) of turning their tails to counterbalance the body weight and turn their bodies to level position – ariel May 11 '11 at 03:54
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    @Renesis Good question. Addressed. – Rusty May 11 '11 at 05:45
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    @Rusty Also just read your answer. +1, addressed many angles of the question. – Nicole May 11 '11 at 05:48
  • A related question would be from what height can a cat jump and still survive. – Andrei Vajna May 11 '11 at 09:46
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    I disagree for all those poor cats made fall upside down hundreds of times... What about if it were **you**??? ^^ – neurino May 11 '11 at 11:06
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    What happens if the cat has a slice of bread tied to its back, buttered side up? – Lars Haugseth May 11 '11 at 11:08
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    It depends on which side the butter is applied. –  May 11 '11 at 12:57
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    @Lars Addressed. – Rusty May 11 '11 at 13:31
  • @neurino I'd land flat on my back every time. – Rusty May 11 '11 at 13:43
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    See http://www.straightdope.com/columns/read/1143/do-cats-always-land-unharmed-on-their-feet-no-matter-how-far-they-fall – Jim Balter May 11 '11 at 22:26
  • I knew a cat that had suffered a head injury as a kitten. That cat always landed on his rear end. – David Thornley May 12 '11 at 02:28
  • @Monkey Tuesday, I gotta ask, how do you get so many views on your questions? Kudos to you, but I gotta know your secret! :) – JasonR May 12 '11 at 13:52
  • @David There many studies in this type of thing. They are unpleasant, so I didn't include any. – Rusty May 12 '11 at 14:13
  • @Brightblades I have no idea where all the activity on this question came from. Someone must have linked to it somewhere. – Monkey Tuesday May 12 '11 at 17:02
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    @Monkey @Brightblades Cats have been viewing while their slaves *(aka: owners)* are getting them food. – Rusty May 12 '11 at 21:23
  • @rusty @brightblades Honestly, after this question exploded I can't stop thinking about [this](http://www.youtube.com/watch?v=k2-15mYWpmA) – Monkey Tuesday May 12 '11 at 21:33
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    I'm afraid to report that in his misspent youth my brother tested the limits of this proposition at the low end and reported that one of our neighborhood cats needed roughly 15 inches to turn over completely. A mud puddle was used as incentive and cushioning so the cat was not seriously injured. Damn, but little boys are not human. – dmckee --- ex-moderator kitten Feb 05 '12 at 17:25

1 Answers1

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No. Unless...

  1. The cat is healthy and more than ~seven-weeks old.
  2. If dropped from a height of more than ~1.5 feet and less than ~700 feet.
  3. The vertical velocity of the cat is less than ~60 mph (terminal velocity for cats).

A cat dropped upside-down turns over very rapidly - in fact, it will do so within its own standing height.

“How does a cat fall on its feet?”, The New Scientist, vol. 7, no. 189, pp. 1647-9.

Étienne-Jules Marey experimented on cats by shooting them (Video). With his chronophotographic gun.

enter image description here

The minimum height is a basic physics problem...

...use Newton's law of motion, which says that mass times acceleration is equal to the sum of all the forces acting on the object. Since the cat is falling only a short distance at a fairly low velocity, it is safe to assume that the only force acting on the cat is gravity. Thus,

ma = -mg,

where m is the mass of the cat, a is the acceleration of the cat, and -mg is the force of gravity (assuming up is positive), where g is a constant (g = 979 cm/sec2 at a latitude like San Diego when you add centripetal acceleration to the standard value given for g, which is 980.7 cm/sec2 ).

See: Differential Equations and Integration for all the fun math.

The maximum height and velocity are related. Once weightless the cat has no "down" and might not maintain proper orientation.

When a cat, blindfolded and lying on its back, is dropped, it immediately turns into normal position to land on its feet, indicating that a visual cue is not involved in this spatial orientation. Function of such orientation response of cats was examined during microgravity produced by aircraft parabolic flights. The three-week-old kittens whose postural righting reflex was not developed, floated upside-down in air during weightlessness, whereas in the eight- and twelve-week-old ones whose reflexes were well established, the reflex acted for the initial several seconds but ceased thereafter during the weightless state, with or without blindfold;
Disorientation of animals in microgravity.

However this might not be a bad thing...

What appears to happen is that in falls from above 7 stories, cats have time to reach terminal velocity, the speed at which their drag due to wind resistance equals their weight due to gravity and they stop accelerating. At this speed, the cat relaxes its limbs and is better able to survive the impact (at a slight cost – they get less broken limbs, but more chest injuries).
source

Finally we have this excellent interesting questionable data from the Annals of Improbable Research...

Cats have excellent balance, and are remarkably acrobatic. When turned upside down and dropped from a height, a cat generally has the ability to land on its feet. Until now, no one has systematically investigated the limits of this phenomenon. In this study, I dropped a cat upside down from various heights, and observed whether the cat landed on its feet.

enter image description here

Does a cat land on its feet when dropped from a height of less than one foot? This preliminary study indicates that the answer may be no. However, further experiments, preferably with the same cat, are needed to settle the question.

Does a Cat Always Land on Its Feet ? Fiorella Gambale, Ph.D.

NOTE: A cat with a piece of buttered toast attached to its back, butter side up, will not land on its feet. In fact the forces create by this configuration will cause the cat to hover.

Related cat physics: Cat Swinging. Principles & Mechanics.

Rusty
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    This is epic. +1 for shooting cats, for "See: Differential Equations and Integration for all the fun math", and for the incredible amount of data. MOAR. – Agos May 11 '11 at 09:09
  • Did she really lift up her cat and drop it 600 times? Poor cat – Nobody May 11 '11 at 09:26
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    But did the study factor in quantum mechanic effects? In other words: does Schrödinger's Cat land on its feet? – splattne May 11 '11 at 09:33
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    @splattne Only in the not dead case. – Rusty May 11 '11 at 09:35
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    So the answer is: "No, but most of the time yes." – Andrei Vajna May 11 '11 at 09:43
  • I was watching a tall handsome man in a labcoat, he walked briskly to where I was standing, the man picked me up, and he tried to pet me, but I didn't like, so I gnawed my paw on his palm. The man carried me to a small pedestal overlooking a small room, I heard him shouting to his assistant with words I don't understand, and then he looked at me and smiled widely and then within moments I felt... free... free... fall!!!!! Meoowwww!!!! – Lie Ryan May 11 '11 at 12:37
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    -1! I've dropped my two year old cat from ~2 meters with zero initial velocity and it landed on side, not on feets. It's just a lazy cat :) – blaze May 11 '11 at 13:16
  • @Andrei: I edited it so it was clearer but for some reason Rusty decided it was better in this confusing format. :-/ – MSpeed May 11 '11 at 13:32
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    @billynomates I did not revert your edit. I think we had an edit conflict. Regardless the question is *Do cats **always** land on their feet ?* So I think the answer should stand. Other edits for clarity are certainly welcome. – Rusty May 11 '11 at 13:41
  • @Rusty Oh, sorry. Hmm, I get your point but I still think it's confusing. If this was an every-day conversation, one would probably say "Yes, unless..." because generally, they do! But either way is fine, I guess. – MSpeed May 11 '11 at 13:55
  • Also, if you spin the cat really fast while dropping it will probably not land on its feet. – David Murdoch May 11 '11 at 14:39
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    There's also all sorts of interesting research on the terminal velocity of cats. Their terminal velocity is borderline fatal/non-fatal. Someone has even chucked a cat out of a small airplane to see if it would survive and it did. Someone also did a study on cats that fell off of balconies in New York and found that their survival rate was much higher if they fell from above 8 (or was it 6) stories than it was below that. – Phoenix May 11 '11 at 14:40
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    Here is a video version of the Étienne-Jules Marey experiments http://www.youtube.com/watch?v=Ua4Gh_4XdwQ – Scott Chamberlain May 11 '11 at 15:48
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    @Phoenix: Instead of dropping cats in New York, you should practice with dogs, imho. :) – user unknown May 11 '11 at 16:18
  • @Scott Good idea with the video. I changed your link to the actual Étienne-Jules Marey footage. Very cool. – Rusty May 11 '11 at 17:37
  • Personally I think the "no, but most of the time yes" is the perfect phrasing to answer the question since it includes the word "always" also +1 for addrssing einstein's little known buttered toast/falling cat paradox. – Monkey Tuesday May 11 '11 at 19:46
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    As a result of some of my first ever experiments I can confirm that about a little over a foot of height is is the minimum required space for a typical cat to land on it's feet. Additional note: Expect the cat to fear you for 2 to 3 days after the experiment. – AmaDaden May 12 '11 at 19:21
  • @AmaDaden There's always one. You're the reason Myth Busters et. al. repeat the "Don't try this at home." disclaimer over and over. Maybe it's OK, you do sound like a expert :) *I hope the cat was at least wearing a helmet.* – Rusty May 12 '11 at 19:43
  • @Rusty The video linked in the answer seems to be removed from Youtube: http://www.youtube.com/watch?v=FWdF_UYfIbI&NR=1 – petrichor Feb 04 '12 at 20:35
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    The whole argument built around terminal velocity and "Once weightless the cat has no "down"" is dubious. The body is only "weightless" when its air speed is zero. As it speeds up, it starts to feel air drag, thus *obtaining* the "down" direction, not losing it. Thus, at terminal velocity the feeling of "down" should be maximum, not vanish as the answer seems to imply. Also, in-aircraft testing is useless: the cat can not feel drag in there, can it? – Rotsor Aug 08 '12 at 16:08
  • @Rostor Sorry for not having the source at hand, but I read cats can orient themselves very well when not accelerating, which terminal velocity allows them to do. Also, the NASA funded paper [A dynamical explanation of the falling cat phenomenon](http://ntrs.larc.nasa.gov/search.jsp?R=19690058843&qs=N%3D4294812298%26Nn%3D4294958769%257CSubject%2BTerms%257CATTITUDE%2BCONTROL%257C%257C4294962922%257CSubject%2BTerms%257CYAW) is great in explaining how exactly a cat does all that. – pafau k. Jan 12 '14 at 11:08
  • Here's some [additional evidence](https://www.youtube.com/watch?v=O9XtK6R1QAk) for the weightless cat note. – Jason C Mar 09 '16 at 03:20
  • I'd like to meet the sick bastard who measured the terminal velocity of cats. My morbid curiosity won't let me decide whether I should shake their hand or punch them in the face. – Beefster Jan 01 '20 at 06:07
  • This poor cat was dropped upside down 600 times... – snek programmer Nov 09 '21 at 02:20