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AIRPLANE FLIGHT ANALOGY                           1997 William Beaty

Imagine a huge, disk-shaped helium balloon floating in the air.  The disk
stands on edge.  A small platform sticks out of its rim.  (If you feel the
need, you should imagine a counterweight on the opposite rim to the
platform, so the balloon hovers without rotating.)

            _____
         _--     --_
        /           \    DISK-BALLOON WITH
     __|      .      |   A SMALL PLATFORM
       |             |
        \_         _/
          --_____--

Now suppose I were to leap from the top of a ladder and onto the balloon's
small platform.  The balloon would move downwards.  It would also rotate
rapidly counterclockwise, and I would be dumped off. 

Next, suppose we have TWO giant disk-shaped balloons stacked adjacent to
each other like pancakes.  They do not touch each other.  Both have
platforms.  If I jump onto the first platform, but then I immediately leap
onto the next platform, I can stay up for a tiny bit longer. 

Next, suppose we have a row of these disk-balloons one KM long.  Now I can
run from platform to platform, and I will stay aloft until I run out of
balloons.  Behind me I leave a trail of rotating, downward-moving
balloons.  I can remain suspended against gravity because I am flinging
mass downwards in the form of helium mass trapped inside the balloons.  I
am also doing much more work than necessary, since the energy I expend in
rotating the balloons does not contribute to my fight against gravity. 
(In truth, all my work is really not necessary, I could simply walk along
the Earth's surface with no need to move any massive gasbags!) 

To make the situation more symmetrical, we shall add a second row of
platform-bearing balloons: 

            _____                 _____
         _--     --_           _--     --_
        /           \         /           \    END VIEW OF TWO LONG
       |      .      |__   __|      .      |   ROWS OF DISK-BALLOONS
       |             |       |             |
        \_         _/         \_         _/
          --_____--             --_____--

There's one platform for each of my feet.  I can run forwards, leaving a
trail or "wake turbulence" behind me.  The "wake" is composed of rotating,
descending balloons. 

An aircraft does much the same thing as me and my balloons: it remains
aloft by throwing down a spinning wake of mass.
sive, vortex-threaded
air.  My balloons represent cylindrical parcels of air which can move with
closed streamlines.  Real aircraft use "invisible balloons."  The
"invisible balloons" have no set boundaries, although they contain
significant amounts of constrained mass.

            _____                 _____
         _--     --_           _--     --_
        /           \    |    /           \    FRONT VIEW OF AIRCRAFT,  
       |      -----_____/ \_____-----      |   W/ROTATING AIR MASSES
       |             |  \_/  |             |
        \_         _/         \_         _/
          --_____--             --_____--

If I walk slowly along my rows of balloons, I must leap upwards to each
platform, and each balloon is thrown violently downward.  If I run very
fast, my feet touch each platform briefly, and the situation resembles my
running along the solid ground.  Similarly, if a plane flys slowly, it
must fling the vortex violently downward.  If it flys fast, it needs only
to barely touch each "balloon."  Hence, faster flight is desireable
because it requires that far less work be performed upon the air.

All of my reasoning implies that modern aircraft actually remain aloft by
launching "smoke rings" downwards.  Imagine one of the cars in the old
cartoon 'The Jetsons,' with those little white rings shooting down out of
the underside!  But rather than launching a great number of individual
rings, modern aircraft throw just one very long ring downwards, and they
are lifted by the upward reaction force. 


((((((((((((((((((((( ( (  (   (    (O)    )   )  ) ) )))))))))))))))))))))
William J. Beaty                                  SCIENCE HOBBYIST website
billbeskimo.com                                  http://amasci.com
EE/programmer/sci-exhibits          science projects, tesla, weird science
Seattle, WA   206-762-3818          freenrg-L taoshum-L vortex-L webhead-L