Report of the Second Piloted Aircraft Flight Control System - Acgsc.org

It w ill now be shrnm that the quadrai;ic tern of equation (49)
includes the only dyneaaical parameters considerd in the mlaal flutter
-08, where as the first tern, 4, 4+/4++ , cdpreaents
the correction that must be added to take into account the heretoion
dirregarded chanrcteristics'of the hydnrulic-flutter sprta.
In oldiaary flutter calculations it is the practice to nae
Theodorean~s differential equations of motion, The equation coq,nssing
the .qrrillbrlum of the mcm~ents on a movable &ace is given by:
when
oc = angle of attack
/B - marface angular deflection
X = vertical coordinate of ads of rotation of air~oh
j; = mmt of inertia per unit length of ~uriace (aht hinge
-
me)
static mat of surface (in slugs-feet)
per unit length (about hfnge fie)
5 = torsional stiffness of eurface per uait lcmgth (about hinge
-1
Mp = total aezwlynamic manmt on sariace per unit length
(about hfnge line)
IL = coordinate of ads of rotation of airfoil (percent of
airfoil half chord length)
A = hlf dmrd length of airfoil
c = coordinate of surface hfnge lfne (percent of airfoil
half cord length)
Fig. l4 UlstMtaa &tr,wg.o~etrical pamet era of the girfoil-surfaoe
eabinatimo