K. L. Kosanke
ABSTRACT: Some empirical evidence is presented in support of a recent suggestion by R. K. Norton that a significant portion of aerial shell drift may simply be the result of shell-to-bore clearance. The support for this stems from the observation that aerial shells, during the very earliest portion of their free flight, were occasionally found to deviate from approximately 2.5 to 4 degrees from the axis of the mortar that fired them. At such an early stage in their flight, other possible mechanisms sometimes cited in an attempt to account for aerial shell drift (the magnus effect and other aerodynamic effects) cannot provide the explanation. However, Norton’s suggestion regarding shell-to-bore clearance does provide a ready explanation for this observation. If the effect of shell-to-bore clearance operates during this early portion of a shell’s flight, then certainly it will continue to play a major role in producing deviations from a shell’s trajectory from the mortar’s axis.
Keywords: aerial shell drift, shell clearance
Ref: JPyro, Issue 14, 2001, pp72-73
(J14_72)
© Journal of Pyrotechnics and CarnDu Ltd
