
198 Ballistics: Theory and Design of Guns and Ammunition
The lift force coefcient can be written in its nonlinear form as
αα α
δ
=+
2
(6.8)
With a symmetric projectile, we must note that if there is no angle of attack (i.e., δ = 0) there
is no lift. This is obvious even for the linear case since δ appears in Equation 6.7. Some
authors prefer to work in coordinates other than those we are utilizing here. In those cases,
expressions such as C
x
and C
N
are used for drag and lift, respectively. In these cases, it is
important that proper transformations are used to change the coefcients. An example of
this is provided in Ref. [1].
At this point, ...