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Peregrine Falcon speed claim

  1. Mar 11, 2014 #1
    Every where one reads that Peregrine Falcons can reach speeds of 200+ mph. This seems impossible given the huge amount of air resistance at such speed. Is such possible or is this urban legend?
     
  2. jcsd
  3. Mar 11, 2014 #2

    phinds

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    "Everywhere" is not a recognized citation on this forum.
     
  4. Mar 11, 2014 #3

    Nugatory

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    A human in free fall can reach speeds well in excess of 100 mph, and a peregrine falcon has an appreciably more aerodynamic shape than a human. So the claim is not absurd on the face of it.
     
  5. Mar 11, 2014 #4

    A.T.

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    These are peak dive speeds. In level flight a falcon isn't much faster than a pigeon.
     
  6. Mar 11, 2014 #5
    It's not urban legend.
     
  7. Mar 11, 2014 #6

    phinds

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    A human in freefall has broken the sound barrier, so 200mph doesn't seem impossible.

    He went almost 1,000 mph (mach 1.2+ as I recall)

    http://www.telegraph.co.uk/science/space/9607604/Skydiver-Felix-Baumgartner-attempts-to-break-sound-barrier-live.html [Broken]
     
    Last edited by a moderator: May 6, 2017
  8. Mar 11, 2014 #7

    Baluncore

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    Firstly, welcome to PF.
    Air resistance at 200 mph is only 4 times that at 100 mph.

    There may be many quotes, claims or assumptions that 200 mph is possible.
    Until a reference to an accurate measurement is found, the claim must be treated as unreliable.

    200 mph = 89.4 m/sec, so yes, it does appear to be technically possible.

    http://jeb.biologists.org/content/201/3/403.short
    Download the free PDF from the above link.
    Someone must have put a GPS tracker on a falcon by now.
    It is a case of web searching or following a citations index in the hope of finding that article.
     
    Last edited by a moderator: May 6, 2017
  9. Mar 11, 2014 #8

    CWatters

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    Last edited by a moderator: Sep 25, 2014
  10. Mar 11, 2014 #9

    Baluncore

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    CWatters
    I don't have video bandwidth here, how about a synopsis of the video.
     
  11. Mar 11, 2014 #10

    sophiecentaur

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    It's in the Guinness Book of Records. If that's not a reputable source then what is?
     
  12. Mar 11, 2014 #11

    PeroK

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    Falcon released from aircraft at 12,000 ft dives at 240mph.

    Crazy Brit, complete with obligatory Union Jack crash helmet and specially designed suit, makes like a giant falcon and reaches 300 mph in free fall.
     
  13. Mar 11, 2014 #12

    AlephZero

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  14. Mar 11, 2014 #13

    sophiecentaur

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    Saucy! :biggrin: Most Americans seem to use the 'obligatory' Stars and Stripes whenever possible - even outside their houses. You only find that in the UK during World Cup Fever. We are sooo laid back about these things.
     
  15. Mar 11, 2014 #14

    Nugatory

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    OK, it's off-topic, but I have to offer up a line I heard in a duplicate bridge tournament many years ago: "Only mad dogs and Englishmen bid like that.... and you're no subject of the queen".
     
  16. Mar 11, 2014 #15

    sophiecentaur

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    :approve:
     
  17. Mar 11, 2014 #16

    Baluncore

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    The semiotics of flags can be fascinating.
    There is an interesting sub-concious parallel here. A falcon flies, as does a sky diver, the flag also flies.

    In the USA, flying the Stars and Stripes demonstrated acceptance that the “recent unpleasantness” of the civil war was over. Anyone now not flying the Stars and Stripes is seen as divisive and as an enemy of the economy, which includes the disadvantaged, who cannot afford a flag or a pole to fly it from.

    In Britain, Everyone except the aristocracy was impoverished, so the Union Jack was not needed on every home in the country. There had always been sufficient nationalistic enemies in Europe to unite Britain and maintain the class structure. The rise of the United States of Europe may encourage a resurgence of the Union Jack in Britain as part of a marketing campaign.
     
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