On Tue, 20 Jun 2006 14:00:39 GMT, Larry Dighera wrote:

On Tue, 20 Jun 2006 07:36:13 -0400, Ron Rosenfeld
wrote in
::

On 20 Jun 2006 03:30:46 -0700, wrote:

Is it possible for an aircraft to stall and sink nose-up tail-down
instead of pitching nose-down? Or does aircraft design inherently
preclude that?

Thanks in advance,

Ramapriya

Thinking about it simply, if the airplane is not generating lift, it should
fall with the heaviest end down. For most light GA a/c, the engine is up
front, so that end goes down first.

You may recall, that Galileo Galilei (1564-1642) performed experiments
to verify that heavier bodies do not fall faster than lighter ones,
rather that they fall at the same rate, therefore your analysis is
incorrect.

While it is true, that an airplane in a vacuum will fall in any
orientation, in the atmosphere, it is practically impossible to
prevent the falling airplane's wings from providing some lift. Given
an airplane correctly loaded within its weight and balance envelope,
when the wing is generating lift, the center of lift is located behind
the aircraft's center of gravity. The center of gravity acts as a
fulcrum, and the lifting force aft of the CG is acting in the
direction roughly upward, while the gradational force acts uniformly
on the entire airplane in a downward direction resulting in the nose
dropping as the aircraft was designed.

You're both getting into a more complicated, thoughtful (and accurate)
analysis than I.
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)