The Drag of Projectiles with Truncated Cone Headshapes

摘要

A series of projectiles with truncated conical headshapes (24 deg 12 min included cone angle) were fired in the Aerodynamics Range and their drag was determined from time measurements and spark photographic records of distance. The drag was found to increase linearly with meplat diameters except for small meplats. A comparison was made with pointed cone head projectiles of the same head lengths as the truncated series, the drags of the pointed projectiles being estimated from the measured drag of the 24 deg 12 min complete cone projectile. The drag of the truncated cone projectiles is lower throughout at Mach number 1.65 and for meplat diameters to 0.4 calibers at M 2.35. (Author)