The implementation of a classic three-dimensional PPN guidance against a high-speed nonmaneuvering target is analyzed. All the analysis is performed in a line-of-sight fixed coordinate. By utilizing an auxiliary function inspired from the tangential relative velocity at interception, a necessary and sufficient condition for the airfoil shape capture region for intercepting the target is obtained. In addition, to have a maximum range of the angle between a target velocity and line of sight, the optimal aiming of an interceptor is derived. Finally, a sufficient condition for the capture region with the finite line-of-sight turn rate constraint is also presented.