It seems that everything I read about
lift describes it in terms of effect, not cause, i.e. Lift occurs
because flow is turned downward creating downwash. Well, what made
the air turn downward? Lift occurs when a moving flow of gas
is turned by a
solid object. Just how did this solid object turn it?
Citing Newton's action -reaction still does not explain what caused the
action. And to me, these explanations are not theories in the strictest
sense, they are hypotheses. Until a hypothesis has been reduced to an
actual theory, which completely describes how a process comes about, is
provable, and is accepted by the experts as the real explanation, any
hypothesis has as much validity as any other, regardless of how bizarre it may
seem, such as my "Hose&Kite" hypothesis. The very fact that there are so
many explanations put forth on lift, each one with its own devotees, proves my
point; no one really seems to know what causes the pressure reduction.
Showing all these wonderful pressure diagrams and saying that they are what
causes lift still does not say how these pressure gradients were
generated!
Here's one that really gets to me:
Lift=rho V^2 CL A / 2. That equation implies that dynamic pressure
generates lift. If so, how can it generate 50% more lift than is available from
the dynamic pressure when operating at a CL 1.5? Or even three pounds of lift
per one pound of dynamic pressure when a wing has slats and slotted flaps and
has a CL of 3.0? Is the wing similar to a wedge that takes a linear force and
creates a much greater normal force? So, basically, all these write-ups say one
thing - nobody really knows for certain where lift comes
from!
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