Marson, G. B.
Description:
The pressure drag coefficients of a particular family
of convex logarithmic projectile nose shapes in which the nose
angle is an important parameter have been calculated over a range
of supersonic Mach numbers using a rapid approximate method due
to Zienkiewicz.5
The optimum nose angle for minimum wave drag of these
profiles for each Mach number has been obtained. It is shown
that above N = 1.5„ approximately, the optimum shape is similar
to the hypersonic optimum profile and has the sane or- less wave
drag than this profile. However for values of M/F, where P
is the fineness ratio, below 0.5, both the hypersonic and the
logarithmic optimum profiles have a higher drag than the so-called
cubic profile (Ref, 9).