More on flutter


David J. Gall
 

Good reading, if you can wade through the thick parts:

1956 NACA report "Safegaurds Against Flutter of Airplanes:"
http://naca.larc.nasa.gov/reports/1956/naca-tm-1423/

Note particularly the first sentence of the Preface:

"An infallible method for avoiding flutter would consist in making the
structure very rigid (for instance, twice as rigid as it would be made
according to static calculations) and in perfectly balancing the control
surfaces."

No doubt....

The third paragraph of the Preface reads thus:

"The author stresses particularly all questions concerning the movable
members because in these cases the solution is so simple that application of
the elementary rules may a priori avoid any error. However, one must not
lose sight of the fact that the most dangerous cases of flutter are those
which concern the natural modes of the tail for which the only rules are
practically: high rigidity, weight toward the front."

Rudder information starts on page 34.

Ryan, I assume you're having no difficulty figuring out how much weight to
use and where to put it...?


David J. Gall
P.S. John, shouldn't the subject line of your last post have been "Low Speed
Flutter!" instead of "High Speed Flutter!"? 120 mph isn't very fast.... ;)

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