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Re: too easy?

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On 8/12/2023 2:01 PM, RichD wrote:
> On August 10, J. J. Lodder wrote:
>> In horizontal flight there are four forces,
>> Lift Drag, Thrust and Weight.
>> For steady horizontal flight Thrust must equal Drag,
>> and Lift must equal Weight.
>> L/D could be infinite.
>> For a real wing L/D will be about 10.
>> So to move through the air at speed v requires a power P of v times D.
>> So the fundamental equation for steady horizontal flight is
>> v = L/D . P/W, or P = vWD/L
> 
> You forgot buoyancy B.  The atmosphere is liquid.

Liquids are not compressible. End of story.

> If you pump air into a plane at high pressure, and heat
> to high temperature, it will float, no fuel needed.

Bzzzzzzttttttt! Even if you remove the atmosphere completely
from any modern airplane it will remain heavier than air. Floating
requires weight less than the amount of air displaced by the plane.

I'm shocked by this posting, worse even than Laurence's ignorance
of the basics.

> Hydrogen, even better -

Nope.

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too easy? nero <oldogf@yahoo.it> - 2023-08-09 17:17 -0700
  Re: too easy? whodat <whodaat@void.nowgre.com> - 2023-08-09 20:51 -0500
  Re: too easy? whodat <whodaat@void.nowgre.com> - 2023-08-09 21:48 -0500
    Re: too easy? nero <oldogf@yahoo.it> - 2023-08-10 16:45 -0700
    Re: too easy? nero <oldogf@yahoo.it> - 2023-08-10 16:48 -0700
  Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-10 11:37 +0200
    Re: too easy? nero <oldogf@yahoo.it> - 2023-08-10 16:52 -0700
      Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-11 12:53 +0200
    Re: too easy? nero <oldogf@yahoo.it> - 2023-08-10 16:54 -0700
    Re: too easy? RichD <r_delaney2001@yahoo.com> - 2023-08-12 12:01 -0700
      Re: too easy? whodat <whodaat@void.nowgre.com> - 2023-08-12 14:16 -0500
        Re: too easy? Volney <volney@invalid.invalid> - 2023-08-12 17:31 -0400
        Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-13 10:34 +0200
      Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-13 10:34 +0200
        Re: too easy? nero <oldogf@yahoo.it> - 2023-08-13 18:19 -0700
          Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-14 10:30 +0200
        Re: too easy? RichD <r_delaney2001@yahoo.com> - 2023-08-15 10:17 -0700
          Re: too easy? Athel Cornish-Bowden <athel.cb@gmail.com> - 2023-08-15 21:02 +0200
          Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-15 23:38 +0200
            Re: too easy? RichD <r_delaney2001@yahoo.com> - 2023-08-16 09:25 -0700
              Re: too easy? Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-08-16 09:47 -0700
              Re: too easy? Paul Alsing <pnalsing@gmail.com> - 2023-08-16 17:51 -0700
                Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-17 09:45 +0200
                Re: too easy? patdolan <patdolan@comcast.net> - 2023-08-17 11:31 -0700
              Re: too easy? Tom Roberts <tjoberts137@sbcglobal.net> - 2023-08-17 13:03 -0500
  Re: too easy? Sylvia Else <sylvia@email.invalid> - 2023-08-11 11:40 +1000
    Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-11 12:53 +0200
      Re: too easy? Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-08-11 11:02 -0700
        Re: too easy? patdolan <patdolan@comcast.net> - 2023-08-11 11:33 -0700
          Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-11 21:01 +0200
        Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-11 20:54 +0200
          Re: too easy? Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-08-11 14:38 -0700
            Re: too easy? nospam@de-ster.demon.nl (J. J. Lodder) - 2023-08-12 12:07 +0200
    Re: too easy? nero <oldogf@yahoo.it> - 2023-08-18 18:38 -0700

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