<DOC>
<DOCNO>
814
</DOCNO>
<TITLE>
stability derivatives of cones at supersonic speeds .
</TITLE>
<AUTHOR>
tobak,m. and wehrend,w.r.
</AUTHOR>
<BIBLIO>
naca tn.3788, 1956.
</BIBLIO>
<TEXT>
  the aerodynamic stability derivatives due to pitching velocity and
vertical acceleration are calculated by use of potential theory for circular
cones traveling at supersonic speeds .  the analysis is based on
two theoretical techniques used successfully previously in application
to the case of uniform axial and inclined flow .  in the first,
potential solutions for axial flow and crossflow are derived from the
first-order wave equation but in application to calculations for the
forces no approximations are made either to the tangency condition or
to the isentropic pressure relation .  the second method consists in
combining the first-order crossflow potential with an axial-flow
potential correct to second order .  closed-form solutions by both
methods are found for a cone, and numerical results for the stability
derivatives are presented as a function of mach number for cones having
semivertex angles of 10 and 20 .
  in addition, expressions for the forces, moments, and stability
derivatives of arbitrary bodies of revolution are obtained using
newtonian impact theory .  numerical results for cones compare well
with those obtained from the combined first- and second-order potential
theory at the highest mach number for which the latter theory is
applicable .
</TEXT>
</DOC>
