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Tornadoes are known to throw 18 wheelers and other large objects into the air. However, most deaths (to humans) are due to debris rather than being thrown by the wind itself.

There are several claims that twisters have lifted cows into the air:

Several cows and one bull survived being carried more than a quarter mile by a tornado Tuesday evening near Elgin. The cattle were reportedly tossed over fences into an adjacent pasture.

(Perhaps most famously, it was depicted in a CGI scene from the movie Twister (1996).)

From a physics perspective sky-bound cows seem unlikely. The houses and cars that tornadoes play with are very heavy but also hollow and low density. Solid objects are much harder to move. A human terminal velocity is about 120 mph in a belly-down position (maximizing drag) but humans can fall at a speed of up to 310 mph in a streamlined vertical dive. This is faster than the most powerful tornado on record. A cow, which can weigh over a tonne, presumably could fall at a velocity of well above 200mph. Terrified cows may find themselves in odd places, and debris are still highly lethal. But flight?

The poorly-resolved "cow" in the first film could be a piece of siding or other debris. Instead of "being carried over a fence" terrified bovines simply jumped and/or trampled the damaged(?) fence. The article provides no evidence besides "someone said so".

Has there been a well-documented "flying cow"?

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  • Comments are not for extended discussion; this conversation has been moved to chat.
    – tim
    Commented Jan 28, 2023 at 8:37

2 Answers 2

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I wrote this before I realized this is the same video linked in the question. Rather than deleting it, I think digging into its background and the credibility of the source is worth an answer even if it is not definitive.

Stormchaser and AccuWeather Extreme Meteorologist Reed Timmer, PhD claims to have seen cows flying through the air. His credentials lend this more credibility than other claims.

From Reed Timmer details the heart-pounding moments from 5 of his most extreme storm chases in 2018

Tornado in Federal, Wyoming... May 27 he chased a tornado on a flat tire for about 10 miles. He knew that if he had stopped to fix it, he would have missed the storm completely. The EF2 twister was around 2 to 3 miles in length, according to the National Weather Service. Estimated peak winds were approximately 111-135 mph. “Sadly, it hit some farmhouse there and I saw cows flying through the air,” said Timmer. “That’s the first time that I have seen with my own eyes livestock flying through the air inside a tornado.”

Reed has video of the event on his YouTube channel. At 1:09 he exclaims "Cows! Cows going through the air!". The video is pretty indistinct, you decide.

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  • 4
    I just realized this is the same video linked in the question. I think digging into its background and the credibility of the source is worth an answer.
    – Schwern
    Commented Jan 24, 2023 at 7:14
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    Sorry but those are not cows. Clearly the cameraman was caught in the heat of the moment, when he confused that debris for livestock. Commented Jan 24, 2023 at 17:59
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    @NoseKnowsAll, yeah, I looked at this video full screen on my 49" 4K TV at 1/4 speed, and those aren't cattle. I grew up on a farm with friends and family having cattle, so I know what they look like. The things in the air weren't that. It looks more like sheet metal or maybe a tarp, but not cattle. Even at 1080p, the resolution isn't good enough to see any real detail. The fact that they disappear at times makes me think they are something flat, but sometimes folded into a rough shape of an animal. Also, it horses are roughly the same shape and size as cattle, so positive id is unlikely. Commented Jan 24, 2023 at 21:02
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    135mph is around cruise speed of Cessna 172 light aircraft. That plane has wings and is in general not shaped like a cow, but weight is in same ballpark. There's no way that you make me believe that a cow would fly at 135mph.
    – vidarlo
    Commented Jan 25, 2023 at 6:26
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    @vidarlo that's not flying. It's falling. With style. 135mph is the ground speed of the wind. We're talking about a tornado. They're also known to produce an updraft. Belly down human skydivers have a terminal velocity of 120 mph. So you have the speed but you measured it in the wrong direction. My point? I doubt these are cows. But I want it disproved with a better argument. Commented Jan 25, 2023 at 13:54
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I could not find any reference for cows. But the effects on strong winds in cyclones or tornadoes are well documented on the Fujita and Enhanced Fujita scales and on a less used but tornado targetted scale the Torro(*) scale.

According to my student memories, the effects of a moving fluid on a solid depend on:

  • the weight of the solid (inversely proportional according to the fundamental law for dynamics: F = m gamma)
  • the surface of the solid (proportional: the larger the surface, the larger the effect)
  • the relative speed between the solid and the fluid

This is consistent with what we observe: a paper sheet or a flat wooden board will hover far better than a compact book, or a wooden ball.

The mass of a cow is expected to be between 600 kg and 1000 kg (ref. on Wikipedia), so slightly half of what we would expect for a car, but its surface is also less than a one half what is expected for a car. So I expect the effect of a tornado on a cow to be slightly lower of what is observed on a car. I must admit it is only an assumption, but I expect it to be conservative.

That being said, the Torro page on tornadoes says (extract):

  • T4 or Severe Tornado at 52-61 m/s (115-136 mph): Motorcars levitated. Mobile homes airborne / destroyed....
  • T5 or Intense Tornado at 62-72 m/s (137-160 mph): Heavier motor vehicles (4x4, 4 Tonne Trucks) levitated.

For the more common Enhanced Fujita scale T4 is more or less EF2, and T5 is roughly EF3 meaning strong tornadoes.

That means that such tornadoes could easily sweep a cow away, and probably levitate it a bit, like they do for motorcars between two shocks on the ground. But even if English is not my first language, the photograph shows something flying in the air much higher than what I would expect for being levitated.

What is cited in Torro scale is that mobile homes can be airborne in T4/EF2 tornadoes, but we now have more than one order of magnitude difference in surface without such a difference in weight. My conclusion is that according to the Torro scale which is consistent with the Enhanced Fujita scale, winds up to 135 mph could sweep a cow away and maybe levitate it but not make it fly.


(*) This site is documented as the reference for the Torro scale on Wikipedia.

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  • A similar answer was deleted yesterday, I wonder if deleted questions should be somehow locked and shaded but still visible to new users the same way it is for high-rep users. It could prevent duplication of effort and prevent people from answering with the same thing.
    – pipe
    Commented Jan 26, 2023 at 13:54
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    @pipe This is by the same person who posted that earlier deleted answer. I can't say whether it's any better than their first attempt because I can't see their first attempt and don't remember what it said.
    – F1Krazy
    Commented Jan 26, 2023 at 14:08
  • My first answer did contain a number of unreferenced assumptions the reason why I deleted it. Here I have tried to cite references with the Torro and Fujita scales which are based on observations. Commented Jan 26, 2023 at 14:50
  • @pipe I can temporarily undelete my previous answer. I am new on this site and honnestly try my best to meet its quality rules. Commented Jan 26, 2023 at 14:55
  • @F1Krazy Image of the deleted answer. The link is about tornado classification.
    – Laurel
    Commented Jan 26, 2023 at 15:59

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