Ballistics, 2nd Edition

293Trajectories

of complex variables and solved it. The particular solution was the (relatively) constant

yaw of repose, and the complimentary solution was the transient epicyclic motion. In the

modied point mass approach, we extract the particular solution and ignore the transient

motion, instead concentrating on the yaw of repose, the drift, and the effect of the yaw

drag. We assume that the epicyclic pitching and yawing motion are negligible everywhere

along the trajectory, i.e., in many instances, reasonable, since it should damp early in the

trajectory and thus contributes little to the drift. We proceed by dening another unit vec-

tor ...